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The level structure of the double-magic nucleus 34Si (Z = 14, N = 20) was investigated by evaluating the available data. On the basis of experimental results from the beta-decay and fusion-evaporation reactions, we established the level scheme by assigning spin-parities up to 61 + at 6233 keV. The high energy positions of the excited states are consistent with the magicity at 34Si, such as the 22 + state of the spherical ground band at 4.519 MeV and the 3-, 4-, and 5- states of the one-particle one-hole cross-shell states at approximately 4.5 MeV. This nucleus, for a long time, has attracted much attention because of, on one side, a proton bubble structure in the ground state and, on the other side, a deformation in the second 0+ state, 02 +. By a comparison of the constructed level scheme with the shell model calculations, we describe the emerging structures in the ground and second 0+ states and the negative-parity 3- states within the framework of the shell model context. We propose a deformed rotational band with the cascading 62 + − 41 + − 21 + transitions built on the 02 + state.

Neutron-rich Pm ( Z = 61 ) isotopes were studied by delayed γ -ray spectroscopy at RIBF, RIKEN Nishina Center using the in-flight fission of a 345 MeV/nucleon U 238 beam. A cluster-type Ge detector array, EURICA, was used to measure the delayed γ rays from stopped ions. Isomeric γ decays were observed in Pm 159 and Pm 161 with half-lives of 4.97(12) μ s and 0.79(4) μ s , respectively. Level schemes for Pm 159 and Pm 161 were constructed in this study. The isomeric states of Pm 159 and Pm 161 could be interpreted as two quasiparticle excitations of neutrons with the configurations of ν ( 7 / 2 [ 633 ] ⊗ 5 / 2 [ 523 ] ) and ν ( 7 / 2 [ 633 ] ⊗ 1 / 2 [ 521 ] ) , respectively. They are analogous to the isomers that have been observed systematically in other even-mass N = 98 and N = 100 isotones in this region. A projected shell model calculation was performed and it reproduced the order of three-quasiparticle states only if new Nilsson parameters with an N -dependent spin-orbit interaction were used. This work demonstrates that the strength of spin-orbit interactions in standard Nilsson parameters needs to be modified to study the properties of neutron-rich rare-earth nuclei around A = 165 , and provides new evidence supporting the existence of the deformed N = 98 subshell gap in odd-mass nuclei for the first time.

We investigated the effects of molecular ordering on the electro-optical characteristics of organic light-emitting diodes (OLEDs) with an emission layer (EML) of poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylenevinylene] (MEH-PPV). The EML was fabricated by a solution process which can make molecules ordered. The performance of the OLED devices with the molecular ordering method was compared to that obtained through fabrication by a conventional spin coating method. The turn-on voltage and the luminance of the conventional OLEDs were 5 V and 34.75 cd/m2, whereas those of the proposed OLEDs were 4.5 V and 120.3 cd/m2, respectively. The underlying mechanism of the higher efficiency with ordered molecules was observed by analyzing the properties of the EML layer using AFM, SE, XRD, and an LCR meter. We confirmed that the electrical properties of the organic thin film can be improved by controlling the molecular ordering of the EML, which plays an important role in the electrical characteristics of the OLED.

The level structure of I124 (Z=53, N=71) has been studied via the Sn122(Li7,5n)I124 reaction with a beam energy of 54 MeV. Through in-beam and out-of-beam ?-ray spectroscopy, the sophisticated low-lying levels including isomeric states and numerous collective states have been established for the first time. A positive-parity collective band built on the 10+ state at 1297 keV is interpreted as being associated with the combination of a proton and a neutron in the same intruder h11/2 orbital, namely the ph11/2?h11/2 configuration. This band shows a typical quadrupole vibrational character. In contrast, the negative parity bands based on the pg7/2?h11/2 configuration show a soft triaxial rotation. An isomeric 8- state at 689 keV with a half-life of 14 ns can be explained as a K isomer due to a proton with an ?p=9/2 in the g9/2 orbital coupled to a neutron with an ?n=7/2 in the h11/2 orbital. The excited states based on this pg9/2?h11/2 configuration show a coupled rotational structure. Another coupled rotational band built on the 6+ state at 714 keV is thought to be based on the pg9/2?d3/2 configuration.

15 pags., 10 figs., 4 tabs., Newly observed decay schemes of the nuclei Sb137 and Sb138 are reported. The neutron-rich Sb isotopes were produced by the in-flight fragmentation of a U238 primary beam with an energy of 345 MeV/nucleon. Several new excited states of Te137 with tentatively assigned spin-parities of (5/2-), (9/2-), and (7/2) have been established which play an important role in the evolution of neutron levels beyond N=82. The study of the ß decay of Sb138 led to a considerable extension of the level scheme of Te138 including the identification of several nonyrast states. The structure of Te137 and Te138 is discussed on the basis of large-scale shell-model calculations performed using two different effective interactions., This work was carried out at the RIBF operated by RIKEN Nishina Center and CNS, University of Tokyo. Part of the WAS3ABi was supported by the Rare Isotope Science Project (RISP) of the Institute for Basic Science (IBS) funded by the Ministry of Science, ICT and Future Planning (MSIP) and National Research Foundation (NRF) of the Republic of Korea (Grant No. 2013M7A1A1075764). This research was supported by NRF of the Republic of Korea (Grants No. 2019R1A6A3A03031564 and No. 2018R1A5A1025563), IBS of the Republic of Korea (Grants No. IBS-R031-D1 and No. IBS-R031-Y1), the Spanish Ministerio de Economía y Competitividad (Grant No. FPA2017-84756-C4-2-P), and JSPS KAKENHI of Japan (Grant No. 25247045). The support from FR-JP LIA is also acknowledged. C.S.L. acknowledges the support from NRF of the Republic of Korea (Grants No. 2017M2A2A6A02071071 and No. 2016R1D1A1A09917463). Z.V. acknowledges the supports from the National Research, Development and Innovation Fund of Hungary, financed under the K18 funding scheme with Project No. K128947 and by the European Regional Development Fund (Grant No. GINOP-2.3.3-15-2016- 00034), as well as by the National Research, Development and Innovation Office NKFIH (Grant No. PD 124717).

6 pags., 4 figs., 2 tabs., The change of the shell structure in atomic nuclei, so-called “nuclear shell evolution”, occurs due to changes of major configurations through particle-hole excitations inside one nucleus, as well as due to variation of the number of constituent protons or neutrons. We have investigated how the shell evolution affects Gamow-Teller (GT) transitions that dominate the β decay in the region below 132Sn using the newly obtained experimental data on a long-lived isomer in 127Ag. The T1/2=67.5(9) ms isomer has been identified with a spin and parity of (27/2+) at an excitation energy of 1942−20+14 keV, and found to decay via an internal transition of an E3 character, which competes with the dominant β-decay branches towards the high-spin states in 127Cd. The underlying mechanism of a strong GT transition from the 127Ag isomer is discussed in terms of configuration-dependent optimization of the effective single-particle energies in the framework of a shell-model approach., Part of the WAS3ABi was supported by the Rare Isotope Science Project which is funded by MSIP and NRF of Korea. This work was supported by the Priority Centers Research Program in Korea (2009-0093817), OTKA contract number K100835, the U.S. DOE, Office of Nuclear Physics (Contract No. DE-AC02-06CH11357), NRF2016R1A5A1013277 and NRF-2013M7A1A1075764, the Spanish Ministerio de Economía y Competitividad under contract FPA2017- 84756-C4-2-P, the European Commission through the Marie Curie Actions call FP7-PEOPLE-2011-IEF (Contract No. 300096), German BMBF under Contract No: 05P12PKFNE, JSPS KAKENHI Grant No. 24740188 and 25247045, the National Natural Science Foundation of China (Nos. 11505302, 11575112, 11775316), the National Key Program for S&T Research and Development (No. 2016YFA0400501), and STFC (UK).

The $\beta$-decay half-lives of 55 neutron-rich nuclei $^{134-139}$Sn, $^{134-142}$Sb, $^{137-144}$Te, $^{140-146}$I, $^{142-148}$Xe, $^{145-151}$Cs, $^{148-153}$Ba, $^{151-155}$La were measured at the Radioactive Isotope Beam Factory (RIBF) employing the projectile fission fragments of $^{238}$U. The nuclear level structure, which relates to deformation, has a large effect on the half-lives. The impact of newly-measured half-lives on modeling the astrophysical origin of the heavy elements is studied in the context of $r$ process nucleosynthesis. For a wide variety of astrophysical conditions, including those in which fission recycling occurs, the half-lives have an important local impact on the second ($A$ $\approx$ 130) peak.

We report for the first time two distinctive features in the odd–odd nucleus 120I: a pair of doublet bands and a high-spin isomer built on the π h 11 / 2 ν h 11 / 2 configuration. For producing the excited states of 120I, a fusion-evaporation reaction 118Sn(6Li, 4n) at E = l a b 48 MeV was employed. The beam was provided by the 14UD tandem accelerator of the Heavy Ion Accelerator Facility at the Australian National University. The observed doublet structure built on the positive-parity states is the first case and unique in isotopes with Z = 53 . The emerging properties are indicative of the known chiral characteristics, leading to a doubling of states for the π h 11 / 2 ν h 11 / 2 configuration. In contrast, the high-spin isomer with a half-life of 49(2) ns at spin-parity J π = 25 + can be explained in terms of a noncollective oblate structure with the full alignment of six valence nucleons outside the 114Sn core: three protons ( g 7 / 2 ) 1 ( d 5 / 2 ) 1 ( h 11 / 2 ) 1 and three neutrons ( h 11 / 2 ) 3 . This is an outstanding case that reveals a pure single-particle structure consisting of equal numbers of valence protons and neutrons outside the semi-double shell closure of 114Sn with Z = 50 and N = 64 .

This paper serves to give brief overviews of key issues in five case studies in engineering technology stand-alone project based courses within a standard scholastic framework. The courses were offered in a range of scenarios with significant international student participation. The subject material focused on optics, opto-electronics and electronics. Topics covered in this work include; issues with managing scope, issues with adapting to open ended problem solving, and, confusion between method based teaching and guided projects. The main purpose of this paper is to share findings on preparing and delivering project based courses that are developed within a pre-existing system of courses and with a pre-existing limit of facilities.

Physics letters / B 762, 404 - 408 (2016). doi:10.1016/j.physletb.2016.09.058, Published by North-Holland Publ., Amsterdam

The level structure of the odd-odd iodine nucleus I122 has been studied by the Sn120 (Li7, 5n)I122 reaction at Elab=58 MeV. Two chopped beams from the 14UD (Unit Doubled) tandem heavy-ion accelerator at the Australian National University were used; one was a nanosecond (ns) pulsed-beam with separation of 1.7 microseconds (μs) and the second one was a 60-μs beam separated by 880μs. Through in-beam and out-of-beam γ-ray spectroscopy, the complex proton-neutron multiplet states, including isomers with half-lives of a few tens of ns to a few tens of μs, have been identified. Collective states based on the proton h11/2 orbital exhibit two kinds of structure depending upon the coupled neutron orbital: a quadrupole vibration when involving the h11/2 orbital and a γ-soft deformed rotation when involving the g7/2 orbital. With spherical shell model and deformed shell-model calculations, the observed level structures are explained.

The neutron-rich isotopes of palladium have attracted considerable interest in terms of the evolution of the N=82 neutron shell closure and its influence on the r-process nucleosynthesis. In this Letter, we present the first spectroscopic information on the excited states in Pd and Pd studied using the EURICA γ-ray spectrometer, following production via in-flight fission of a high-intensity U beam at the RIBF facility. New isomeric states with half-lives of 144(4) ns and 39(6) μs have been assigned spins and parities of (23/2 ) and (19/2 ) in Pd and Pd, respectively. The observed level properties are compared to a shell-model calculation, suggesting the competition between proton excitations and neutron excitations in the proton-hole and neutron-hole systems in the vicinity of the doubly magic nucleus Sn.

The decay of a new four-quasiparticle isomeric state in 160Sm has been observed using γ-ray spectroscopy at the RIBF, RIKEN. The four-quasiparticle state is assigned a 2 π ⊗ 2 ν π 5 2 − [ 532 ] , π 5 2 + [ 413 ] , ν 5 2 − [ 523 ] , ν 7 2 + [ 633 ] configuration. The half-life of this ( 11 + ) state is measured to be 1.8(4) μs. The ( 11 + ) isomer decays into a rotational band structure, based on a ( 6 − ) ν 5 2 − [ 523 ] ⊗ ν 7 2 + [ 633 ] bandhead, consistent with the g K − g R values. This decays to a ( 5 − ) two-proton quasiparticle state, which in turn decays to the ground state band. Potential energy surface and blocked-BCS calculations were performed in the deformed midshell region around 160Sm. They reveal a significant influence from β 6 deformation and that 160Sm is the best candidate for the lightest four-quasiparticle K isomer to exist in this region. The relationship between reduced hindrance and isomer excitation energy for E1 transitions from multiquasiparticle states is considered with the new data from 160Sm. The E1 data are found to agree with the existing relationship for E2 transitions.

The neutron-rich dysprosium isotopes ¹⁶⁸Dy₁₀₂ and ¹⁶⁹Dy₁₀₃ have been investigated using the EURICA γ-ray spectrometer, following production via in-flight fission of a high-intensity uranium beam in conjunction with isotope separation through the BigRIPS separator at RIBF in RIKEN Nishina Center. For ¹⁶⁸Dy, a previously unreported isomer with a half-life of 0.57(7) μs has been identified at an excitation energy of 1378 keV, and its presence affirmed independently using γ-γ-γ coincidence data taken with Gammasphere via two-proton transfer from an enriched ¹⁷⁰Er target performed at Argonne National Laboratory. This isomer is assigned Jπ = Kπ = (4⁻) based on the measured transition strengths, decay patterns, and the energy systematics for two-quasiparticle states in N = 102 isotones. The underlying mechanism of two-quasiparticle excitations in the doubly midshell region is discussed in comparison with the deformed QRPA and multi-quasiparticle calculations. In ¹⁶⁹Dy, the B(E2) value for the transition de-exciting the previously unreported Kπ = (1/2⁻) isomeric state at 166 keV to the Kπ = (5/2⁻) ground state is approximately two orders of magnitude larger than the E2 strength for the corresponding isomeric-decay transition in the N = 103 isotone ¹⁷³Yb, suggesting the presence of a significant γ-vibrational admixture with a dominant neutron one-quasiparticle component in the isomeric state.

International audience; Excited states in the neutron-rich nucleus 150Ba have been observed via β–γ spectroscopy at the Radioactive Isotope Beam Factory, RIKEN Nishina Center. The 150Ba ions were produced by the in-flight fission of a 238U beam with an energy of 345 MeV/nucleon. The E(2+) energy of 150Ba was identified at 100 keV, which is the lowest known in the neutron-rich Ba isotopes. A γ -ray peak was also observed at 597 keV. A mean-field calculation with a fully 3D real space was performed and a static octupole deformation was obtained for the Ba isotopes. Kπ = 0− and 1− excited states with significant octupole collectivity were newly predicted at around or lower than 1 MeV on the ground state of 150Ba by a random-phase approximation calculation. The 597 keV γ ray can be interpreted as a negative-parity state, showing that 150Ba may possess octupole collectivity.

This contribution will report on the experimental work on the level structure of 168Dy. The experimental data have been taken as part of the EURICA decay spectroscopy campaign at RIBF, RIKEN in November 2014. In the experiment, a 238U primary beam is accelerated up to 345 MeV/u with an average intensity of 12 pnA. The nuclei of interest are produced by in-flight fission of 238U impinging on Be target with a thickness of 5 mm. The excited states of 168Dy have been populated through the decay from a newly identified isomeric state and via the β decay from 168Tb. In this contribution, scientific motivations, experimental procedure and some preliminary results for this study are presented.

Blue phosphorescent organic light-emitting diodes (PHOLEDs) were fabricated using double dopants FIrpic and FIr6 in emissive layer (EML) with structure of ITO/NPB (700 A)/mCP:FIrpic-8%:FIr6- x % (300 A)/TPBi (300 A)/Liq (20 A)/Al (1200 A). We optimized concentration of the second dopant FIr6 in the presence of a fixed FIrpic to observe its effect on electrical performance of PHOLED device. 24.8 cd/A of luminous efficiency was achieved by the device with dopant ratio of 8%FIrpic:4%FIr6 in EML. Efficiency roll-off was also improved 20% compared to the PHOLED device singly dopped with FIrpic or FIr6 only. Second doping proved its effect in stabilizing charge balance in EML and enhancing energy transfer of triplet excitons between two dopants.

The KOBRA (KOrea Broad acceptance Recoil spectrometer and Apparatus) is a multi-purpose recoil spectrometer for low-energy nuclear experiments at the RAON accelerator complex. It is divided into two stages based on the operational function: the first stage (F0–F3) is an in-flight separator or beam transport line, and the second stage (F3–F5) is a large acceptance spectrometer. For spectrometers using radioactive ion (RI) beams, high performance, such as high resolution and large acceptance, are especially required due to the limit of quality of RI beams. In this respect, a dispersion-matching technique and a movable magnet system were employed for high resolution and large acceptance, respectively. Reaction spectra at the focal plane for the dispersion matching mode were obtained and analyzed using a Monte Carlo simulation code. In addition, the geometrical angular acceptances with respect to the distance between the reaction target and the first Q-pole doublet of the second stage were calculated, and the expected maximum solid angle of the spectrometer was estimated.

We report for the first time the β-decay scheme of Te140 (Z=52) to I140 (Z=53), with a specific focus on the Gamow-Teller strength along N=87 isotones. These results were obtained in an experiment performed at the Radioactive Ion Beam Factory (RIBF), RIKEN, where the parent nuclide, Te140, was produced through the in-flight fission of a U238 beam at 345 MeV per nucleon impinging on a Be9 target. Based on data from the high-efficiency γ-ray spectrometer, EUROBALL-RIKEN Cluster Array (EURICA), we constructed a decay scheme of I140. The half-life of Te140 has been determined to be 350(5) ms. A level at 926 keV has been assigned as a (1+) state based on the logft value of 4.89(6). This (1+) state, commonly observed in odd-odd nuclei, can be interpreted in terms of the πh11/2νh9/2 configuration formed by the Gamow-Teller transition between a neutron in the h9/2 orbital and a proton in the h11/2 orbital. We observe a sharp contrast to this type of β-decay branching to the lower-lying 1+ states between I140 and I136, where we see a large reduction as the number of neutrons increases. This is in contrast to the prediction by large-scale shell model calculations. To investigate this type of the suppression, results of the Nilsson model calculations will be discussed. Along the isotones with N=87, we discuss a characteristic feature of the Gamow-Teller distributions at 1+ states with respect to the isospin difference.

One of the most successful descriptions of the structure of atomic nuclei is the spherical shell model. It, however, becomes impractical when moving away from closed-shell nuclei. Instead, it is the interplay between the macroscopic shape degrees of freedom and the microscopic nature of the underlying single-particle structure in a deformed basis that determines the nuclear structure. Being the heaviest nucleus precisely in the middle of, known, closed proton and neutron shells, $^{170}$Dy has become a central calibration point for tests of collective models of nuclear physics. However, besides one candidate transition from a previous experiment in Legnaro, Italy, no experimental information is available for this nucleus. Using the EURICA setup at RIKEN, which couples the worlds highest intensity in-flight fission facility with a high-efficiency HPGe array, an experiment in November 2014 produced $^{170}$Dy nuclei by in-flight fission of a $^{238}$U beam. The results from this experiment provide a wealth of information on this elusive nucleus, including the evolution of quadrupole collectivity, rigidity and higher order deformations, as well as the long sought for isomeric $K=6^+$ state, predicted to be exceptionally pure at mid-shell. These results provide us with a rich level scheme for discussing both single-particle and collective structures at mid-shell.

We study for the first time the internal structure of Te140 through the β-delayed γ-ray spectroscopy of Sb140. The very neutron-rich Sb140 nuclei with Z=51 and N=89 were produced by the in-flight fission of U238 beams at the Radioactive Isotope Beam Factory, RIKEN. The half-life and spin-parity of Sb140 are reported as 173±12 ms and 3−, respectively. In addition to the excited states of Te140 produced by the β-decay branch, the β-delayed one-neutron and two-neutron emission branches were also established. By identifying the first 2+ and 4+ excited states of Te140, we found that Te isotopes persist in their vibrator character with E(4+)/E(2+)=2. We discuss the distinctive features manifest in this region revealed in pairs of isotopes with the same neutron holes and particles with respect to N=82.

© The Authors, published by EDP Sciences, 2017. This short paper presents the identification of a metastable, isomeric-state decay in the neutron-rich odd-odd, prolate-deformed nucleus 166Tb. The nucleus of interest was formed using the in-flight fission of a 345 MeV per nucleon 238U primary beam at the RIBF facility, RIKEN, Japan. Gamma-ray transitions decaying from the observed isomeric states in 166Tb were identified using the EURICA gamma-ray spectrometer, positioned at the final focus of the BigRIPS fragments separator. The current work identifies a single discrete gamma-ray transition of energy 119 keV which de-excites an isomeric state in 166Tb with a measured half-life of 3.5(4) μs. The multipolarity assignment for this transition is an electric dipole and is made on the basis internal conversion and decay lifetime arguments. Possible two quasi-particle Nilsson configurations for the initial and final states which are linked by this transition in 166Tb are made on the basis of comparison with Blocked BCS Nilsson calculations, with the predicted ground state configuration for this nucleus arising from the coupling of the v(1-/2)[521] and π(3+/2) Nilsson orbitals. ispartof: EPJ Web of Conferences vol:146 ispartof: ND 2016: International Conference on Nuclear Data for Science and Technology location:Bruges, Belgium date:11 Sep - 16 Sep 2016 status: Published online

This research presents fabrication process of an encapsulation layer for organic light-emitting diodes(OLED) and its optical performance. We have developed a novel encapsulation layer for organic light-emitting diodes(OLEDs) using poly(dimethysiloxane) (PDMS) including scattering particles. This encapsulation layer can be fabricated by the solution process. The OLED with the proposed encapsulation layer has an excellent optical performance. The external quantum efficiency(EQE) has been improved by 42%. We expect the proposed encapsulation layer will be used where EQE is a key factor.

White organic light-emitting diodes(WOLEDs) were fabricated with the device structure of ITO(1800 A)/NPB(700 A)/emissive layer(300 A)/Bphen(300 A)/Liq(20 A)/Al(1200 A) using the two complementary colors method. Then, we investigated their electrical and optical characteristics to determine luminous efficiency, luminance and color coordinates of single, double, triple and quadruple emissive layered-WOLED. Thickness of emissive layer was fixed at 30 A, and DPASN and BAlq were used for blue emissive host material and DCJTB was added as red dopant in the emissive layer. Then, we investigated the performance of OLEDs via its charge blocking structure and its different emissive region with emissive layers. Luminous efficiency of 5.30 cd/A at 50 mA/cm2 of current density is obtained in WOLED device with double emissive layer of DPASN:DCJTB-0.1% (150 A)/BAlq:DCJTB-0.1% (150 A) and these are 80% higher than WOLED device with single emissive layer of DPASN:DCJTB-0.1% (300 A).

We investigated the optical properties of light emission based on the resonance energy transfer mechanism between two molecules in the host–dopant systems. For this purpose, we fabricated the organic light-emitting devices with the different doped emissive layers. The host matrices were made of 4,4′,4″-tris(carbasol-l-nyl)triphenylamine (TCTA) and 2-methyl-9,10-di(2-naphthyl)anthracene (MADN) molecules and the doped molecules were 5,6,11,12-tetraphenylnaphtacene (Rubrene) and 4-(Dicyanomethylene)-2-tert-butyl-6-(1,1,7,7-tetramethyljulolidin-4-yl-vinyl)-4H-pyran (DCJTB). The concentrations of the doped molecules were 0.1%, 0.3%, 0.5%, and 0.8%. Through spectroscopic analysis using multi-peak fits with a Gaussian function to the emission spectra, we obtained the relative light intensity of the two dopants according to the doping concentrations and examined the relations between the molecular excited energy states and the nature of energy transfer in the host and dopant systems. We show that the luminous efficiency of the devices has a strong correlation between the energy transfer owing to the individual molecular intrinsic properties and the electrical characteristics associated with the bulky properties in the devices.

The neutron-rich nuclei $^{158,160}\mathrm{Nd}$ have been studied via delayed $\ensuremath{\gamma}$-ray spectroscopy of $\ensuremath{\mu}\mathrm{s}$ isomeric states at the RIBF facility, RIKEN. These nuclei were produced following the projectile fission of a 345 $A\phantom{\rule{0.16em}{0ex}}\mathrm{MeV}\phantom{\rule{4pt}{0ex}}^{238}\mathrm{U}$ beam and delayed $\ensuremath{\gamma}$ rays were detected by the EURICA cluster Ge array. The isomeric states have measured half-lives of 339(20) ns and 1.63(21) $\ensuremath{\mu}\mathrm{s}$ for $^{158}\mathrm{Nd}$ and $^{160}\mathrm{Nd}$, respectively. From the observed $\ensuremath{\gamma}$ decays and the systematics of levels in the neighboring Nd isotopes first level schemes were constructed for these nuclei. The isomeric states of $^{158,160}\mathrm{Nd}$ have been assigned spins of $({6}^{\ensuremath{-}})$ and $({4}^{\ensuremath{-}})$, with proposed $\ensuremath{\nu}5/2[523]\ensuremath{\bigotimes}\ensuremath{\nu}7/2[633]$ and $\ensuremath{\nu}1/2[521]\ensuremath{\bigotimes}\ensuremath{\nu}7/2[633]$ configurations, respectively.

To achieve the emissive layers in white organic light-emitting diode (WOLED) for the three primary colors, DCJTB doped in Alq3, C545T doped in Alq3, and BCzVBi doped in MADN were applied for red, green, and blue emissive layer, respectively. By stacking all the red, green, and blue emissive layers in a single device, WOLED devices with the color coordinates close to (0.33, 0.33) were successfully fabricated. The structure of the blue–green–red (BGR) type of the three primary color WOLED device was NPB(700 A)/MADN:BCzVBi-13%(210 A)/Alq3:C545T-2%(30 A)/Alq3:DCJTB-2%(60 A)/Alq3(300 A)/Liq(20 A)/Al(1000 A). Its maximum luminance and luminous efficiency were 25,680 cd m−2 and 3.79 cd A−1, as well as its white color coordinate was (0.32, 0.31) at 7 V. The structure of blue–red–green (BRG) type of the three primary color WOLED device was NPB(700 A)/MADN:BCzVB-13%(210 A)/Alq3:DCJTB-2%(30 A)/Alq3: C545T-2%(60 A)/Alq3(300 A)/Liq(20 A)/Al(1000 A). Its maximum luminance and luminous efficiency were 26,010 cd m−2 and ...

This paper uses the results of the characterization of amorphous semiconductor thin film transistors (TFTs) with the quasi-permanent memory structure referred to as silicon oxide nitride semiconductor (SONOS) gates, to model spiking neural circuits. SONOS gates were fabricated and characterized. In addition, MOSFETs using organic copper phthalocyanine (CuPc) were fabricated with these SONOS gates to demonstrate proof of concept performance. Analog spiking circuits were then modeled using these low performance TFTs to demonstrate the general suitability of organic TFTs in neural circuits. The basic circuit utilizes a standard comparator with charge and discharge circuits. A simple Hebbian learning circuit was added to charge and discharge the SONOS device. The use of these elements allows for the design and fabrication of high-density 3-dimensional circuits that can achieve the interconnect density of biological neural systems.

In this article we report on the first spectroscopic information on $_{51}^{140}\mathrm{Sb}_{89}$ and the observation of an isomer in this nucleus with ${T}_{1/2}=41(8)$ $\ensuremath{\mu}\mathrm{s}$. It is located in close proximity to $^{140}\mathrm{Sn}$ for $N=90$, where the $\ensuremath{\nu}{f}_{7/2}$ orbit is completely filled. The possible origin of the isomeric state is a $\ensuremath{\pi}{g}_{7/2}^{1}\ifmmode\times\else\texttimes\fi{}\ensuremath{\nu}{f}_{7/2}^{\ensuremath{-}1}$ coupling configuration, resulting in a $({6}^{\ensuremath{-}})$ or $({7}^{\ensuremath{-}})$ spin-parity. This is likely caused by an inversion of the $\ensuremath{\pi}{g}_{7/2}$ and $\ensuremath{\pi}{d}_{5/2}$ orbitals at $N=89$. The existence of such an isomer far from stability is discussed extensively in the context of shell-model calculations and compared to results from mean-field calculations performed using a deformed Woods-Saxon potential. Both approaches suggest the observation of a single-particle excitation mode at an extreme neutron number.

For the high luminance and quantum efficiency, we propose a novel structure of white organic light-emitting diode (WOLED) using two white emissive layers (EML). The host material of MADN with the blue dopant of BCzVBi and the red dopant of DCJTB was used for one EML and DPVBi as host material with those dopants for the other EML. By considering the order of the EMLs and their energy band gaps in the device structure, the charge carrier trapping can be generated. They play a role in the barrier function at the EML enhancing the recombination where the holes and electrons were trapped in the DPVBi and MADN. The quantum efficiency can be improved by the charge carrier trapping in the WOLED with the double white EMLs as obtaining 4.23% at 10 mA/cm 2 , and it is vastly superior to that of the WOLED with a single EML. White color balance is also excellent with color coordinates of (0.36, 0.34) in the CIE 1931 ( x , y ) chromaticity diagram.

See paper for full list of authors; The Korea Rare Isotope Accelerator, currently referred to as KoRIA, is briefly presented. The KoRIA facility is aimed to enable cutting-edge sciences in a wide range of fields. It consists of a 70 kW isotope separator on-line (ISOL) facility driven by a 70 MeV, 1 mA proton cyclotron and a 400 kW in-flight fragmentation (IFF) facility. The ISOL facility uses a superconducting (SC) linac for post-acceleration of rare isotopes up to about 18 MeV/u, while the SC linac of IFF facility is capable of accelerating uranium beams up to 200 MeV/u, 8 pμA and proton beams up to 600 MeV, 660 μA. Overall features of the KoRIA facility are presented with a focus on the accelerator design.

We theoretically study the light outcoupling efficiency of top-emitting organic light-emitting diode (OLED) with inverted structure and thin-film encapsulation. Thin-film optics is used to optimize the layer thickness to obtain high transmittance. Dipole mode is used to analyze the light outcoupling efficiency of the top-emitting OLED. Through this process, we can optimize the thin-film thickness with high transmittance and optimize the outcoupling efficiency of OLED. Compared with previous research, the current design method is a novel process.

We report new data on the $^{136}\mathrm{Sb}\phantom{\rule{4pt}{0ex}}{6}^{\ensuremath{-}}$ yrast isomer with ${T}_{1/2}=489(40) \mathrm{ns}$ and $\ensuremath{\pi}{g}_{7/2}^{1}\ifmmode\times\else\texttimes\fi{}\ensuremath{\nu}{f}_{7/2}^{3}$ configuration, populated in the projectile fission of $^{238}\mathrm{U}$ on a $^{9}\mathrm{Be}$ target. The analysis confirms the lifetime, providing a good accuracy measurement. In addition, the decay of the isomer to the ground state is newly suggested. Our result for the isomeric decay scheme is in a good agreement with shell-model calculations.

We propose an organic photovoltaic (OPV) device with the energy conversion layer. In this structure, the energy conversion layer is formed on the outer surface of the conventional P3HT:PCBM solar cells. Rubrene layer is used for the spectral down-conversion layer. Rubrene layer absorbs the ultraviolet light and re-emits visible light, wavelengths of which coincide with the optical absorption spectrum range of the photoactive layer of the solar cell. In this paper, the thickness effects of the energy conversion layer on the energy conversion efficiency of the OPV device were demonstrated. Considerable increase about 1.5 times in the efficiency was achieved.

In this contribution the low-excitation structural properties of the doubly mid-shell nucleus 170Dy are discussed, with a special empasis on the evolution of the ground state rotational band within the dysprosium isotopic chain. Recent results from an experiment with the EURICA setup at RIKEN are shown in the context of previous measurements at the PRISMA+CLARA as well as the PRISMA+AGATA setups at Laboratori Nazionali di Legnaro. A brief outlook on future planned measurements is also given.

Excited states in the N=102 isotones 166Gd and 164Sm have been observed following isomeric decay for the first time at RIBF, RIKEN. The half-lives of the isomeric states have been measured to be 950(60) and 600(140) ns for 166Gd and 164Sm, respectively. Based on the decay patterns and potential energy surface calculations, including β6 deformation, a spin and parity of 6- has been assigned to the isomeric states in both nuclei. Collective observables are discussed in light of the systematics of the region, giving insight into nuclear shape evolution. The decrease in the ground-band energies of 166Gd and 164Sm (N=102) compared to 164Gd and 162Sm (N=100), respectively, presents evidence for the predicted deformed shell closure at N=100.