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In order to disclose the polarization mechanism of the tilted-foil technique, systematic experimental studies were performed through direct observations of the nuclear polarization of short-lived beta-emitters. The present studies concentrated on the mechanisms of the following processes: (1) production of atomic polarization in the beam–tilted-foil interaction, (2) polarization transfer between an atom and a nucleus, and (3) enhancement of nuclear polarization by the beam multi-tilted-foil interaction. The present results have confirmed the plausibility of a previous model in which the atomic-polarization process in the tilted-foil technique is attributed to the right–left asymmetry of the electron-capture process at the final surface of a tilted foil. The enhancement effect of nuclear polarization by the multi-tilted-foil technique could be consistently explained by a model proposed by Goldring and Niv. Further information on atomic processes is required to make a definite statement on hyperfine interactions and atomic configurations, which contribute to polarization transfer.

The nuclear magnetic dipole moment mu and electric quadrupole moment Q of the beta-emitting 16N(Ipi = 2(-), T(1/2) = 7.13 s) nucleus have been determined for the first time by detecting its beta-NMR in a MgO crystal and beta-NQR (nuclear quadrupole resonance) in a TiO (2) crystal to be /mu/ = (1.9859+/-0.0011) mu(N) and /Q/ = (17.9+/-1.7) mb, respectively. Although the prediction of mu given by the Hartree-Fock calculation agrees well with the experiment, an abnormally small effective charge for neutrons is required to account for the experimental Q.

Nuclear structure of proton-rich unstable nucleus 28P has been studied by measuring its g-factor for the first time. The g-factor of 28P (Iπ = 3+, T1/2 = 270.3 ms) was measured by means of β-NMR technique combined with the new polarization technique for charge exchange reaction product in the intermediate energy heavy ion collisions. The obtained g-factor of g = 0.1028(27) is very much quenched from the Schmidt value, but is well reproduced by the shell model (+0.102). In connection with the magnetic moment of the mirror partner and the β-ray transition probability, the orbital angular momenta and intrinsic spins of protons and neutrons have been determined as 〈lp〉 = 0.43(29), 〈ln〉 = 1.85(29), 〈Sp) = 0.28(4), and 〈Sn〉 = 0.44(4).

Reaction cross sections ( σ R ) for 8 B on Be, C and Al targets were measured at energies of 40 A and 60 A MeV. The density distribution of 8 B was studied through a χ 2 -fitting procedure on the σ R including the high-energy data using the optical limit of Glauber theory with assumptions on the enhancement of the σ R at low energies. The result shows a long tail in the density distribution. Large one-proton removal cross sections were also observed to support the existence of a long proton tail consistent with its binding energy.

The quadrupole moments of the short-lived β -emitting nuclei 13 O ( I π = 3/2 − , T 1/2 = 8.6 ms), 19 O ( I π = 5/2 + , T 1/2 = 27 s) and 21 F ( I π = 5/2 + , T 1/2 = 4.3 s) were determined to be | Q ( 13 O)| = 11.0 ± 1.3 mb, | Q ( 19 O)| = 3.7 ± 0.4 mb and | Q ( 21 F)| = 110 ± 22 mb by detecting their β -NMR. The present results are compared with the theoretical values obtained by the Hartree Fock calculations taking their one nucleon-separation energies into account.

The nuclear magnetic-dipole moment μ and electric-quadrupole moment Q of the short-lived β-emitting nucleus 19 O (I π =5/2 + ,T 1/2 =27 s ) have been determined by detecting its β-NMR in CaO and TiO2 crystals to be |μ|=(1.53195±0.00007) μ N and |Q|=(3.7±0.4) mb, respectively. Slight deviations of both values from the shell model predictions given by Hartree-Fock calculations demand further experimental and theoretical studies.

The β-ray angular distributions from purely spin aligned 12B and 12N were precisely remeasured using a further refined spin-manipulation technique. We determined the amount of a g-parity violating induced tensor form factor in a weak axial vector current as 2M fT/fA= +0.22 ± 0.05\ (stat.) ± 0.15\ (syst.) ± 0.05\ (theor.). The result is consistent with the theoretical prediction in the framework of which induced tensor form factor is proportional to u- and d-quark mass difference. To study the g-parity violation in weak nucleon current systematically, we have started to measure the alignment correlation terms of 8Li, 8B, 20F and 41Sc.

Hyperfine interactions of 8Li impurity nucleus imbedded in ferromagnetic Ni metal were studied using the β-NMR technique. Two kinds of hyperfine fields B82 were found, corresponding to two different final sites of Li atoms in the Ni lattice. The nuclear spin-lattice relaxation times T1 of 8Li in Ni were also determined for each field. Temperature dependencies of B82 and T1 were observed to deduce these values at T=0 K that can be compared with those calculated recently by Akai et al.

The spin manipulation technique by use of the β-NMR is further refined, based on the recent thorough studies of hyperfine interactions of 12B and 12N in Mg. By using this technique, the alignment correlation terms in the β-ray angular distribution of the A = 12 system are precisely measured, so that the axial charge is singled out to be y = 4.66 ± 0.06 (stat.) ± 0.13 (syst.) which shows clear mesonic enhancement over the impulse value.

The sign of the quadrupole coupling constant eqQ of 8B in ZrB2 is determined to be positive through the β-delayed α-ray anisotropy measurement combined with the spin manipulation technique by use of the β-NMR. According to the theoretical calculation of the electric field gradient in ZrB2, the sign of the quadrupole moment of 8B is deduced to be positive.

We studied the electric quadrupole interactions of Oxygen isotopes in a TiO2 single crystal. For 13O and 19O nuclei, quadrupole coupling constants were measured by the β-NMR technique, and for the 17O nucleus the FT-NMR technique was utilized. We synthesized a TiO2 single crystal which was enriched in 17O up to 5 atom % to observe NMR signals without any perturbations from impurities. Using the known quadrupole moment of 17O, EFGs at an O site in TiO2 and the quadrupole moments of 13O and 19O were determined.

The quadrupole moment of the β -emitter 12 N( I π =1 + , T 1/2 =11 ms) has been measured to be Q ( 12 N)=+9.8±0.9 mb by use of a modified β -NMR method. The present result is 3 times smaller than the value which was deduced from the photoproduction cross-section of pions on 12 C, while it is twice the shell-model prediction based on the Cohen-Kurath wave functions in the Woods-Saxon potential.

Kinematical selection works efficiently to polarize reaction products in both low energy direct reactions and heavy ion reactions at a wide range of energy. This polarization technique has been applied to β-ray correlation-type experiments. In such studies, the asymmetry parameter for the 23 Mg β decay was measured to be A = −(0.606 ± 0.007). The alignment correlation coefficients for 12 B and 12 N β decays were determined to be α − = 0.0107 ± 0.0053%/MeV and α + = − (0.2841 ± 0.0072)%/MeV.

The Surface Ocean CO2 Atlas (SOCAT) is an effort by the international marine carbon research community. It aims to improve access to carbon dioxide measurements in the surface oceans by regular releases of quality controlled and fully documented synthesis and gridded fCO2 (fugacity of carbon dioxide) products. SOCAT version 2 presented here extends the data set for the global oceans and coastal seas by four years and has 10.1 million surface water fCO2 values from 2660 cruises between 1968 and 2011. The procedures for creating version 2 have been comparable to those for version 1. The SOCAT website (http://www.socat.info/) provides access to the individual cruise data files, as well as to the synthesis and gridded data products. Interactive online tools allow visitors to explore the richness of the data. Scientific users can also retrieve the data as downloadable files or via Ocean Data View. Version 2 enables carbon specialists to expand their studies until 2011. Applications of SOCAT include process studies, quantification of the ocean carbon sink and its spatial, seasonal, year-to-year and longer-term variation, as well as initialisation or validation of ocean carbon models and coupled-climate carbon models.

Air-sea CO2 fluxes over the Pacific Ocean are known to be characterized by coherent large-scale structures that reflect not only ocean subduction and upwelling patterns, but also the combined effects of wind-driven gas exchange and biology. On the largest scales, a large net CO2 influx into the extra-tropics is associated with a robust seasonal cycle, and a large net CO2 efflux from the tropics is associated with substantial inter-annual variability. In this work, we have synthesized estimates of the net air-sea CO2 flux from a variety of products drawing upon a variety of approaches in three sub-basins of the Pacific Ocean, i.e., the North Pacific extra-tropics (18° N–66° N), the tropical Pacific (18° S–18° N), and the South Pacific extra-tropics (44.5° S–18° S). These approaches include those based on the measurements of CO2 partial pressure in surface seawater (pCO2sw), inversions of ocean interior CO2 data, forward ocean biogeochemistry models embedded in the ocean general circulation models (OBGCMs), a model with assimilation of pCO2sw data, and inversions of atmospheric CO2 measurements. Long-term means, inter-annual variations and mean seasonal variations of the regionally-integrated fluxes were compared in each of the sub-basins over the last two decades, spanning the period from 1990 through 2009. A simple average of the long-term mean fluxes obtained with surface water pCO2 diagnostics and those obtained with ocean interior CO2 inversions are –0.47 ± 0.13 Pg C yr–1 in the North Pacific extra-tropics, +0.44 ± 0.14 Pg C yr–1 in the tropical Pacific, and –0.37 ± 0.08 Pg C yr–1 in the South Pacific extra-tropics, where positive fluxes are into the atmosphere. This suggests that approximately half of the CO2 taken up over the North and South Pacific extra-tropics is released back to the atmosphere from the tropical Pacific. These estimates of the regional fluxes are also supported by the estimates from OBGCMs after adding the riverine CO2 flux, i.e., –0.49 ± 0.02 Pg C yr–1 in the North Pacific extra-tropics, +0.41 ± 0.05 Pg C yr–1 in the tropical Pacific, and –0.39 ± 0.11 Pg C yr–1 in the South Pacific extra-tropics. The estimates from the atmospheric CO2 inversions show large variations amongst different inversion systems, but their median fluxes are consistent with the estimates from climatological pCO2sw data and pCO2sw diagnostics. In the South Pacific extra-tropics, where CO2 variations in the surface and ocean interior are severely under-sampled, the difference in the air-sea CO2 flux estimates between the diagnostic models and ocean interior CO2 inversions is larger (0.18 Pg C yr–1). The range of estimates from forward OBGCMs is also large (−0.19 to −0.72 Pg C yr–1). Regarding inter-annual variability of air-sea CO2 fluxes, positive and negative anomalies are evident in the tropical Pacific during the cold and warm events of the El Niño Southern Oscillation in the estimates from pCO2sw diagnostic models and from OBGCMs. They are consistent in phase with the Southern Oscillation Index, but the peak-to-peak amplitudes tend to be higher in OBGCMs (0.40 ± 0.09 Pg C yr–1) than in the diagnostic models (0.27 ± 0.07 Pg C yr–1).

This study produced maps of the partial pressure of oceanic carbon dioxide (pCO2sea) in the North Pacific on a 0.25° latitude × 0.25° longitude grid from 2002 to 2008. The pCO2sea values were estimated by using a self-organizing map neural network technique to explain the non-linear relationships between observed pCO2sea data and four oceanic parameters: sea surface temperature (SST), mixed layer depth, chlorophyll a concentration, and sea surface salinity (SSS). The observed pCO2sea data was obtained from an extensive dataset generated by the volunteer observation ship program operated by the National Institute for Environmental Studies. The reconstructed pCO2sea values agreed rather well with the pCO2sea measurements, the root mean square error being 17.6 μatm. The pCO2sea estimates were improved by including SSS as one of the training parameters and by taking into account secular increases of pCO2sea that have tracked increases in atmospheric CO2. Estimated pCO2sea values accurately reproduced pCO2sea data at several stations in the North Pacific. The distributions of pCO2sea revealed by seven-year averaged monthly pCO2sea maps were similar to Lamont-Doherty Earth Observatory pCO2sea climatology and more precisely reflected oceanic conditions. The distributions of pCO2sea anomalies over the North Pacific during the winter clearly showed regional contrasts between El Niño and La Niña years related to changes of SST and vertical mixing.

The magnetic moments of the proton drip-line nuclei13O(Iπ = 3/2−,T1/2 = 8.6 ms) and 9C(Iπ = 3/2−,T1/2 = 126 ms) have been determined for the first time through the combined techniques of polarized radioactive nuclear beams andβ-NMR detection. The observed magnetic moments are ¦μ(13O)¦ = 1.3891 ±0.0003μN and ¦μ(9C)¦ = 1.3914 ±0.0005μN. Spin expectation values 〈σ〉 are deduced to be 0.76 and 1.44 for13O and9C, respectively. While the 〈σ〉 of13O is consistent with the systematics from isospinT= 1/2 mirror pairs, the 〈σ〉 of9C is unusually large, even far larger than the single particle value, 〈σ〉 = 1.

The spin relaxation timeT 1 for short-lived beta emitters13O and23Mg implanted in Pt have been measured for the first time;T 1T13O) = 2.90 ±0.65 Ks andT 1 T(23Mg) = 1665 ±140 Ks. The Knight shift for13O in Pt was measured at 300 K to beK(13O) = +(4.23 ±0.14) × 10−3. In the case of13O, the Knight shift is unusually large and the relaxation time is unusually fast compared with other interstitial impurities in Pt. A KKR band-structure calculation reproduces the present large Knight shift fairly well.

The magnetic moment of the proton drip-line nucleus C-9(I(sup (pi)) = 3/2, T(sub 1/2) = 126 ms) has been measured for the first time, using the beta-NMR detection technique with polarized radioactive beams. The measure value for the magnetic moment is 1mu(C-9)! = 1.3914 +/- 0.0005 (mu)N. The deduced spin expectation value of 1.44 is unusually larger than any other ones of even-odd nuclei.

Research and development in the robotics of rehab and power assistance have recently focused on pneumatically driven robots. This is because of their low cost, light weight, and a simple design. We are able to build safe and flexible drives. We took particular note of a Mckibben pneumatic actuator as a drive mechanism for pneumatically driven robots. We developed a low-pressure, low-volume pneumatic actuator in previous studies. However, the generative force of these actuators is small, when you use a equipment like that used for rehab assistance. We originally developed membrane pneumatic actuators to solve this problem. A five-fingered robot hand was developed, that imitated a human's right hand with membrane pneumatic actuators. First, we present the characteristics of a pneumatic actuator from our experiment. Then, we constructed a model using results from another experiment in a one-link arm with membrane pneumatic actuators. Next, a PI-D control system was constructed, and its gains were determined by simulation. Then, we tried to control the pressing force of a one-link arm with the controllers we constructed. As a result, we could control the pressing force with the constructed PI-D controllers.

We examined potential interferences from water vapor and atmospheric background gases (N2, O2, and Ar), and biases by isotopologues of target species, on accurate measurement of atmospheric CO2 and CH4 by means of wavelength-scanned cavity ring-down spectroscopy (WS-CRDS). Variations in the composition of the background gas substantially impacted the CO2 and CH4 measurements: the measured amounts of CO2 and CH4 decreased with increasing N2 mole fraction, but increased with increasing O2 and Ar, suggesting that the pressure-broadening effects (PBEs) increased as Ar < O2 < N2. Using these experimental results, we inferred PBEs for the measurement of synthetic standard gases. The PBEs were negligible (up to 0.05 ppm for CO2 and 0.01 ppb for CH4) for gas standards balanced with purified air, although the PBEs were substantial (up to 0.87 ppm for CO2 and 1.4 ppb for CH4) for standards balanced with synthetic air. For isotopic biases on CO2 measurements, we compared experimental results and theoretical calculations, which showed excellent agreement within their uncertainty. We derived empirical correction functions for water vapor for three WS-CRDS instruments (Picarro EnviroSense 3000i, G-1301, and G-2301). Although the transferability of the functions was not clear, no significant difference was found in the water vapor correction values among these instruments within the typical analytical precision at sufficiently low water concentrations (< 0.3%V for CO2 and < 0.4%V for CH4). For accurate measurements of CO2 and CH4 in ambient air, we concluded that WS-CRDS measurements should be performed under complete dehumidification of air samples, or moderate dehumidification followed by application of a water vapor correction function, along with calibration by natural air-based standard gases or purified air-balanced synthetic standard gases with isotopic correction.

While we may realize commercialization of SOFC systems in the very near future, continuous challenges will be needed to develop advanced fuel cells with higher efficiency, higher durability, better flexibility, as well as lower production cost. For realizing next-generation SOFCs, we may apply a broad range of knowledge related to (1) electrolyte and (2) electrode materials for cell development as well as (3) explore alternative fuels. This entry gives an overview on possible alternative approaches for these three important aspects to realize advanced high-performance SOFCs in a future generation.

Long-term monitoring of carbon monoxide (CO) mixing ratios in the atmosphere over the Pacific Ocean is being carried out on commercial cargo vessels participating in the National Institute for Environmental Studies Voluntary Observing Ships program. The program provides a regular platform for measurement of atmospheric CO along four cruising routes: from Japan to Oceania, from Japan to the United States, from Japan to Canada, and from Japan to Southeast Asia. Flask samples are collected during every cruise for subsequent analysis in the laboratory, and in 2005, continuous shipboard CO measurements were initiated on three of the routes. Here, we describe the system we developed for onboard measurement of CO mixing ratios with a commercially available gas filter correlation CO analyzer. The fully automated system measures CO in ambient air, and the detector sensitivity and background signals are calibrated by referencing the measurements to a CO-in-air standard gas (~1 ppmv) and to CO-free air scrubbed with a catalyst, respectively. We examined the artificial production of CO in the high-pressure working gas standards (CO balanced with purified air at ppmv levels) during storage by referencing the measurements to CO standard gases maintained as our primary scale before and after use on the ships. The onboard performance of the continuous CO measurement system was evaluated by comparing its data with data from laboratory analyses of flask samples using gas chromatography with a reduction gas detector. The reasonably good consistency between the two independent measurement methods demonstrated the good performance of both methods over the course of 3–5 yr. The continuous measurement system was more useful than the flask sampling method for regionally polluted air masses, which were often encountered on Southeast Asian cruises.

The nuclear quadrupole moment of 41Sc(Iπ = 7−2, T12 = 0.596 s) has been measured to be |Q(41Sc; 7−2)| = 16.6 ± 0.8 fm2, by use of a modified β-NMR technique. Combining the value with its mirror quadrupole moment Q(41Ca; 7−2), it is shown that the valence proton in 41Sc carries more than 90% of the moment, and that of the remaining core carries about 10%. This is consistent with the picture that the core of 41Sc, 40Ca, is deformed by about e = −(0.44 ± 0.22)%.

The magnetic moment of 23 Mg (I π = 3 2 + , T 1 2 =11.3 s ) has been determined to be |μ( 23 Mg )| = 0.5364±0.0003 μ N by means of a β-NMR detection with recoil polarization obtained through a nuclear reaction. The deduced spin expectation values are in agreement with the systematic behavior of the mirror doublets in the sd shell.

The quadrupole coupling constants of8Li and12B in hcp Mg and Zn are determined by use of a newly developed nuclear quadrupole resonance technique (NNQR) as ¦eqQ(8Li in Mg)/h¦=3.0±0.3 kHz, ¦eqQ(8Li in Zn)/h¦=33.5±2 kHz, and ¦eqQ(12B in Mg)/h¦=47.0±0.1 kHz. Correspondingly, the electric field gradients at room temperature are deduced: ¦q(8Li in Mg)¦=(3.81±0.39)×1018, ¦q(8Li in Zn)¦=(4.25±0.27)×1019, and ¦q(12B in Mg)¦=(1.47±0.03)×1020, all in V/m2. The experiments are compared with the results of first-principles super-cell band structure calculations which can treat local lattice relaxations around the impurity nuclei. The calculations show that the most favorable location of these light interstitials in hcp Mg is not the octahedral-like sites which have the biggest interstitial volume, but the basal trigonal sites with a local lattice expansion of as big as 30%. Calculated electric field gradients at the impurity nuclei reproduce the experimental values fairly well.

In order to study the basic mechanism of polarization enhancement realized by the multitilted foil technique, nuclear polarization of short-lived beta-emitter8B(T1/2=769 ms,Iπ=2+) was induced. Utilizing up to ten tilted foils, the polarization enhancement was measured as a function of the foil numbers. The observed enhancement for8B was combined with the previous results for12B(Iπ=1+,T1/2=20 ms) which has the same atomic configurations but different nuclear spin. Analyzing these results in the framework of the classical vector model, the essential features of the enhancement depending on the nuclear spin was disclosed.

To disclose the basic mechanisms of nuclear polarization creation realized by the tilted foil technique, hyperfine quantum beats of the nuclear polarization of the short-lived beta-emitter8Li(Iπ=2+,T1/2=840 ms) were measured as a function of the distance between two tilted foils. From the observed beats of the8Li nuclear polarization, it was found that the Fermi-contact interaction of the8Li nucleus with the ground 1s-electron in LiIII plays a main role in the final stage of polarization transfer from polarized orbital electrons to the8Li nucleus.

Recent improvements in isotope separators can be utilized along with the availability of a wide range of nuclear species from the heavy-ion fragmentation process to study hyperfine interactions. We have measured the magnetic moments of mirror nuclei using this method at the Lawrence Berkeley Laboratory's Bevalac heavy-ion accelerator. We present the merits, applicability and limitations of the technique.

Spin polarization of43Ti produced through the projectile fragmentation process in46Ti on C collisions at 116 MeV/nucleon has been observed as a function of fragment momentum by means of beta-decay asymmetry. From the momentum dependence of the fragment polarization, it was concluded that negative angle deflection of the43Ti fragment due to the nuclear attractive potential is the main reaction path in the case of light targets.

The nuclear quadrupole moment of8B(I π=2+,T 1/2=769 ms) has been determined by use of a modified β-NMR detection as |Q(8B)|=68.3±2.1 mb, which is twice the prediction of the Cohen-Kurath shell model calculation. The anomalous quadrupole moment which is carried mainly by the protons in the nucleus, has been accounted for by the proton halo effect.

To complete the systematic study on hyperfine interactions of light impurities in ferromagnetic Ni, the short-lived beta-emitter8Li was implanted in a thin polycrystal Ni foil. One of the final sites of8Li in Ni was found by means of the beta-NMR technique andits hyperfine field was determined to be -3.65(3) kOe. Simultaneously, the spin lattice relaxation time of8Li at the site in Ni was found to be 1.6(4) s. Based on the comparison between these values and theoretical predictions recently made by a first principle calculation, the probable site of8Li in Ni is implied to be an octahedral interstitial site.

NMR on the beta emitter43Ti has been observed by use of the β-NMR technique. From the observed NMR spectrum, the magnetic moment of43Ti was determined to be |μ| =0.85±0.02 µN. The value is significantly quenched from the single particle value −1.91 µN, which shows a strong effect resulting from meson-exchange currents andconfiguration mixing.

The magnetic moment of the23Mg (Iπ=3/2+, T1/2=11.3 s), has been determined as |μ(23Mg)|=0.5364±0.003 µN by use of β-NMR detection with the recoil polarization obtained through a low energy nuclear reaction.

The nuclear quadrupole moment of8B(Iπ=2+,T1/2=769 ms) has been determined by use of a modified β-NMR detection as |Q(8B)|=68.3±2.1 mb. A field gradient was obtained in a single crystal Mg at room temperature.

Quadrupole effects in NMR spectra of8Li(I π=2+;T 1/2=0.84 s) in LiIO3 andLiNbO3 single crystals have been detected by use of a modified β-NMR. The coupling constants for both crystals are in agreement with known ones. Field gradients in the crystals were measured by detecting pulsed-Fourier transformed NMR of7Li. The quadrupole moments deduced from both samples agree, and|Q(8Li; 2+)|=32.7±0.6 mb has been determined.