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We describe an active-set, cutting-plane approach called Constraint Optimal Selection Techniques (COSTs) and develop an efficient new COST for solving nonnegative linear programming problems. We give a geometric interpretation of the new selection rule and provide computational comparisons of the new COST with existing linear programming algorithms for some large-scale sample problems. [ABSTRACT FROM AUTHOR]

Abstract: The anion radical salts in the TCNQ system with 1-ethy1-3-methylimidazolium (EMI) and l-butyl-3-methylimidazolium (BMI) were prepared The 1:1 salts of EMI-TCNQ (1) and BMI-TCNQ (3) melted at 145 and 155°C, respectively, and were stable even in the liquid state. The conductivity of 1 increased by four orders of magnitude at melting owing to the carrier generation by the dissociation of TCNQ dimers and decreased by three orders of magnitude at freezing. [Copyright &y& Elsevier]

Attempts to develop an early detection system of drought effects on agriculture in Eadt and Southeast Asia using the Normalized Difference Vegetation Index (NDVI) derived from the National Oceanic and Atmospheric Administration and the Advanced Very High Resolution Radiometer. Methodology in monitoring and detecting the drought effects in ten day intervals; Creation of the standard and up-to-date NDVI images; Drought monitoring and detection in China.

Listeriolysin O (LLO), a sulfhydryl-activated pore-forming protein from Listeria monocytogenes, was tested and utilized for promoting plasmid DNA (pDNA) delivery into the cytosol of cells in culture. To render pDNA-complexing capability to LLO, the unique cysteine 484 of LLO was conjugated to polycationic peptide protamine (PN) at a 1:1 molar ratio through a reversible, endosome-labile disulfide bond. The sulfhydryl-oxidized LLO construct, LLO-s-s-PN, completely lacked its pore-forming activity, yet regained its original activity upon reduction. The enhanced cytosolic delivery using this construct therefore relies on the requisite reduction of the disulfide bond in LLO-s-s-PN by endogenous cellular reducing capacity. Condensed PN/pDNA complexes incorporating LLO-s-s-PN were tested for their enhanced gene delivery capability monitoring reporter gene expression in HEK293, RAW264.7, P388D1 cell lines and bone-marrow-derived macrophages in the presence of serum. Dramatic enhancement was observed for all tested complexes with varying weight ratios. The effect was most prominent at 0.64-0.80 (w/w) of PN/pDNA upon replacing 1-4% of PN with LLO-s-s-PN, resulting in approximately three orders of magnitude higher luciferase expression compared to PN/ pDNA without apparent toxicity. These results demonstrate that incorporation of endosomolytic LLO into pDNA delivery systems in a controlled fashion is a promising approach of enhancing delivery into the cytosol of target cells in gene delivery strategies. [ABSTRACT FROM AUTHOR]

With the greening of soybean cotyledons after germination, development of the photosynthetic membrane system and particularly granal stacking were correlated with decreasing chlorophyll a/b ratios. Chlorophyll a/b binding proteins are known to be localized mainly in the appressed membrane regions and to have a role in mediating granal membrane appression. The chlorophyll a/b binding protein genes became operative very early in the development of the photosynthetic membrane system and coincided with incipient granal formation. However, the accumulation of chlorophyll a/b binding protein mRNAs decreased as the chloroplasts approached full development. As predicted from the literature, an early amyloplast developmental stage was observed, and prolamellar-like structures appeared early in the development of the chloroplasts, but subsequently disappeared. The reported amoeboid stage that follows the amyloplast phase was not observed, and starch persisted until quite late in development of the chloroplasts. Also, deformations in the shape of the developing chloroplasts indicated that they were amoeboid as they increased in size and as granal formation increased. Phytoferritin accumulations were observed at every stage of development, suggesting that it was not utilized during chloroplast development. [ABSTRACT FROM AUTHOR]

With greening of soybean embryos during seed ripening, increased granal stacking directly correlates with decreasing chlorophyll a/b ratios. However, the intergranal fret system that is normally observed in chloroplasts is minimally developed during embryogenesis. Transitions in chloroplast development were correlated with coincident transitions in cellular ultrastructure. Levels of chlorophyll a/b binding protein mRNAs decreased prior to chloroplast dedifferentiation to coplast during seed maturation. This suggests that the availability of chlorophyll a/b binding proteins is essential for maintenance of thylakoid appression and stacking against [ABSTRACT FROM AUTHOR]

H2TNBP (3,3′,5,5′-tetranitro-4,4′-biphenyldiol) is known as a proton donor forming monoanion HTNBP1− and dianion TNBP2−. We have studied radical salts of TTF-series with TNBP2− as counter anion, and found two kinds of ET (BEDT-TTF) salts, namely 4:1 and 2:1. In the 2:1 salt, it is strongly suggested that the formula is represented as (ET0.5+)2(HTNBP1−) by the optical data and relatively high conductivity. The chemical species of anion part is determined by the chemical shift of 13C-CP/MAS NMR in the solid state. Coexistence of TNBP2− and HTNBP1− is observed in 3:1 BO salt and 2:1 TMTSF salt, though only TNBP2− exists in 4:1 ET salt. The 2:1 TMTSF salt exhibited optical transitions at ca. 2500 and 7500cm−1 simultaneously in the reflection spectrum, however, the intensity ratio differs from crystal to crystal. It suggests that the charge of TMTSF varies between +0.5 and +1.0, and the formula is represented as (TMTSF(1−x/2)+)2(TNBP2−)1−x(HTNBP1−)x(0 < x < 1). [Copyright &y& Elsevier]

Polarimetric Synthetic Aperture Radar (SAR) systems such as ALOS‐PALSAR and Radarsat‐2 can operate in many different modes. The use of additional polarizations may require additional time and operating power and it is important to justify this by increased classification accuracy. A fully polarimetric, dual frequency AIRSAR scene from a rice‐growing area in Japan was classified by a maximum likelihood method based on the Wishart distribution. It is shown how the measured covariance matrices determine the separation accuracy between two classes. Closed form expressions are then given for the expected single‐look accuracy of the maximum likelihood classifier as a function of the class covariance matrices. This can be used to quickly compare the high spatial resolution classification performance of different polarimetric systems to decide upon a particular operating mode. [ABSTRACT FROM AUTHOR]

Differential Scanning Calorimetry (DSC) and optical polarization microscopy of a mixture of the liquid crystalline material (N-(4-methoxybenzylidene)-4-butylaniline, MBBA) and a Fe-based room temperature ionic liquid 1-ethyl-3-methylimidazolium tetrachloroferrate ([Emim]+ [FeCl4]-, EMIF) indicate a decrease in the nematic-isotropic (N-I) phase transition temperature (TNI ) with an increase in EMIF concentration, explained by a proposed model of Coulomb "screening" of MBBA quadrupoles by the EMIF ions along with ionic "self screening." DSC studies of EMIF-MBBA and pure EMIF and comparison with pure MBBA results show that the major transitions in pure EMIF have Arrhenius behaviour, but more importantly the previously found convex Arrhenius behaviour of the pristine MBBA [K. Dan et al., Europhys. Lett. 108, 36007 (2014)] becomes Arrhenius in the mixture, indicating a conversion of the entropic N-I activation barrier to an enthalpic one. In presence of EMIF, a drastic decrease in the intensity of out-of-plane distortions of benzene rings in MBBA is found from Fourier transform infrared spectroscopy, consistent with significant reduction in the conformational states of MBBA. This suppression of large amplitude motion is again consistent with a Coulomb screening and gives a molecular basis for the entropic-to-enthalpic conversion of the N-I activation barrier. [ABSTRACT FROM AUTHOR]

Single crystals of cation radical salts of ethylenedioxy-tetrathiafulvalene (EDO), (EDO)2X (X=PF6, AsF6, ClO4) were prepared by electrocrystallization. Metal–insulator (MI) transitions with big molecular deformation were observed in (EDO)2PF6 at 280 K and in (EDO)2AsF6 at 268 K. Their crystal structures are almost the same at room temperature (RT), and in both cases, the calculated band structures show quasi-one-dimensional electronic nature. The magnetic susceptibility of (EDO)2PF6 and (EDO)2AsF6 showed the thermal hysteresis around 280 and 268 K, respectively, indicating the MI transition being the first-order. Their crystal structures in the insulating phase are isostructural to each other and to that of (EDO)2ClO4 at RT. The structural analysis of these salts revealed that the mechanisms of the MI transitions observed in PF6 and AsF6 salts are the same, which show the cooperative nature of Peierls, charge-ordering (CO), and order–disorder (OD) one. [Copyright &y& Elsevier]

SmFe 12 -based compounds have been considered as promising candidates for next generation permanent magnet materials because of their excellent intrinsic hard magnetic properties with a minimum usage of rare earth elements. However, realizing high coercivity in anisotropic microstructure is a big challenge, which hinders their practical applications. In this work, a novel anisotropic granular microstructure of Sm(Fe 0.8 Co 0.2) 12 with a sufficiently large coercivity (µ 0 H c) of 1.2 T and with a high remanent magnetization of 1.50 T is demonstrated in thin films prepared by co-sputtering Sm(Fe,Co) 12 with boron. Detailed microstructure characterization using high resolution scanning transmission electron microscopy (STEM) and atom probe tomography (APT) indicate that the addition of B leads to the development of columnar-shaped Sm(Fe 0.8 Co 0.2) 12 grains with a size of ∼40 nm, which are surrounded by ∼3 nm-thick B-enriched amorphous intergranular phase. Domain wall pinning at the amorphous grain boundary phase is attributed to the high coercivity. This work provides a guiding principle for realizing high-coercivity anisotropic SmFe 12 -based permanent magnets, which can outperform Nd-Fe-B magnets and could be used as the next-generation high-performance permanent magnets in various applications. Image, graphical abstract [ABSTRACT FROM AUTHOR]

Ionic liquid ion sources (ILISs) are externally wetted and electrochemically etched and sharpened tungsten tips used as electrospraying sources for ionic liquids in a vacuum. They have recently shown an ability to operate as emitters of pure ion beams (no drops), even with ionic liquids of moderate surface tension (γ<40 dyn/cm) and electrical conductivity (K<1 S/m) that had in all prior reports (all based on conventional internally fed capillary tips) always operated in the mixed ion-drop regime. The present study uses time of flight mass spectrometry to analyze full ion beams emitted from ILISs for a diversity of ionic liquids with properties in the wide range 0.26

The emissions of Taylor cones from a wide range of ionic liquids (ILs) have been tested in vacuo in an attempt to identify what physical properties favor the purely ionic regime (PIR). This regime is well known in the case of Taylor cones of liquid metals. For nonmetallic liquids, it has been previously observed in conventional (capillary tube) electrospray sources at room temperature only for the room temperature molten salt (ionic liquid) EMI–BF4 (EMI=1-ethyl-3-methylimidazolium). A large number of other ILs and their mixtures have been studied here, most of which (but not all) are unable to reach the PIR at room temperature. Based on these results and additional theoretical considerations, strong support is assembled for the notion that the PIR is favored by ILs not only of high electrical conductivity but also of high surface tension. This hypothesis is confirmed by tests with three recently synthesized ILs, EMI–GaCl4, EMI–C(CN)3, and EMI–N(CN)2, all of which combine exceptional surface tension and electrical conductivity, and all of which reach the PIR at room temperature far more readily than EMI–BF4. [ABSTRACT FROM AUTHOR]

Presents a study which examined highly conductive thin films of a charge-transfer complex, hepta-(tetrathiafulvalene) pentaiodide formed by double-source evaporation of tetrathiafulvalene and iodine in vacuum. Effect of the orientation of the crystallites by supply rate of iodine; Description of the experiment; Results of the study.

Purpose: Preoperative chemoradiotherapy (CRT) using 5-fluorouracil (5-FU)-based chemotherapy is the standard of care for rectal cancer. The effect of additional chemotherapy during the period between the completion of radiotherapy and surgery remains unclear. Predictive factors for CRT may differ between combination chemotherapy with S-1 and with tegafur-uracil/leucovorin (UFT/LV).Methods: The subjects were 54 patients with locally advanced rectal cancer who received preoperative CRT with S-1 or UFT/LV. The pathological tumor response was assessed according to the tumor regression grade (TRG). The expression levels of 18 CRT-related genes were determined using RT-PCR assay.Results: A pathological response (TRG 1-2) was observed in 23 patients (42.6%). In a multivariate logistic regression analysis for pathological response, the overall expression levels of four genes, HIF1A, MTHFD1, GGH and TYMS, were significant, and the accuracy rate of the predictive model was 83.3%. The effects of the gene expression levels of GGH on the response differed significantly according to the treatment regimen. The total pathological response rate of both high-GGH patients in the S-1 group and low-GGH patients in the UFT/LV group was 58.3%.Conclusion: Additional treatment with 5-FU-based chemotherapy during the interval between radiotherapy and surgery is not beneficial in patients who have received 5-FU-based CRT. The expression levels of four genes, HIF1A, MTHFD1, GGH and TYMS, in tumor tissues can predict the response to preoperative CRT including either S-1 or UFT/LV. In particular, the gene expression level of GGH in tumor tissues may be a useful biomarker for the appropriate use of S-1 and UFT/LV in CRT. [ABSTRACT FROM AUTHOR]

Uniaxial strain was applied along the two-dimensional (2D) conducting plane of a Mott insulator κ-(ET)2Cu2(CN)3 in order to investigate the relation between the crystal and electronic structures and the electronic properties. The strain along both of the crystal axes within the 2D conducting (bc) plane induced a transition from a semiconducting to a metallic state followed by a superconducting transition. By the strain along the c-axis the superconducting transition temperature raised up to 7.3 K that was much higher than that under hydrostatic pressure. [Copyright &y& Elsevier]

We report the effects of uniaxial strain on the single crystals of the organic superconductor κ-(BEDT-TTF)2Cu(NCS)2. The strain was applied to the crystal along the direction parallel to the in-plane c-axis by the epoxy-crystal method. Under the external pressure of 1 kbar, the superconducting transition temperature (TC) increased by about 1 K and simultaneously the resistance peak around 90 K was enhanced, suggesting the significant role of the electron correlation. With further increasing the pressure, both the TC and the peak structure were suppressed. [Copyright &y& Elsevier]

Abstract: The introduction of a methyl group into ethylenedioxytetrathiafulvalene (EDO-TTF) greatly modified the molecular character as a component for the conducting complexes. While the pristine EDO-TTF almost exclusively formed head-to-tail type overlapping with the neighboring donor molecules in the complexes, the methyl substituted compound, MeEDO-TTF, showed both the head-to-head and head-to-tail overlapping patterns. In the former case, the donor molecules interacted with each other in a two-dimensional fashion to provide stable metals along with the charge-ordered complex which exhibited semiconductor-semiconductor first-order transition just above room temperature. The overlapping pattern of MeEDO-TTF directly corresponded to the electronic structure of the complex. In the case of head-to-tail packing patterns, the charge carriers were delocalized only in a quasi-one-dimensional column or in a multimer composed of the donor molecules. The comparison of the intermolecular overlap integrals calculated in the extended Hückel level suggested that at least the magnitude of ca. 10×10−3 is needed for the infinite chain or network of the conducting component molecules to exhibit metallic nature. [Copyright &y& Elsevier]

A quantum spin-liquid phase is an intriguing possibility for a system of strongly interacting magnetic units in which the usual magnetically ordered ground state is avoided owing to strong quantum fluctuations. It was first predicted theoretically for a triangular-lattice model with antiferromagnetically coupled S = 1/2 spins. Recently, materials have become available showing persuasive experimental evidence for such a state. Although many studies show that the ideal triangular lattice of S = 1/2 Heisenberg spins actually orders magnetically into a three-sublattice, non-collinear 120° arrangement, quantum fluctuations significantly reduce the size of the ordered moment. This residual ordering can be completely suppressed when higher-order ring-exchange magnetic interactions are significant, as found in nearly metallic Mott insulators. The layered molecular system κ-(BEDT-TTF)2Cu2(CN)3 is a Mott insulator with an almost isotropic, triangular magnetic lattice of spin-1/2 BEDT-TTF dimers that provides a prime example of a spin liquid formed in this way. Despite a high-temperature exchange coupling, J, of 250 K (ref. 6), no obvious signature of conventional magnetic ordering is seen down to 20 mK (refs 7, 8). Here we show, using muon spin rotation, that applying a small magnetic field to this system produces a quantum phase transition between the spin-liquid phase and an antiferromagnetic phase with a strongly suppressed moment. This can be described as Bose-Einstein condensation of spin excitations with an extremely small spin gap. At higher fields, a second transition is found that suggests a threshold for deconfinement of the spin excitations. Our studies reveal the low-temperature magnetic phase diagram and enable us to measure characteristic critical properties. We compare our results closely with current theoretical models, and this gives some further insight into the nature of the spin-liquid phase. [ABSTRACT FROM AUTHOR]

Abstract: We have studied the electrical conduction of tetrakis(alkylthio)–tetrathiafulvalene (TTC n –TTF) on thin-film field-effect transistors (FET). The field-effect mobility of 10−6–10−5 cm2/Vs was obtained for TTC n –TTF with n =8, 14, and 18. The mobility increased with increase in the length of alkyl chains. The origin of the increase in mobility is attributed to the reduction in intermolecular distance between adjacent TTF moieties caused by the intermolecular interaction through alkyl chains. Consistently, the X-ray diffraction (XRD) experiments showed that the longer alkyl chain gives the shorter distance between the adjacent TTF moieties. The temperature dependence of the mobility for TTC n –TTF shows a change in activation energy at around 220K, which is attributable to the phase transition of TTC n –TTF. [Copyright &y& Elsevier]

Abstract: The spin-density wave (SDW) phase with an incommensurate wave vector is induced as a ground state in the organic compound (TMTTF)2Br under the pressure above 0.5GPa. We investigated the collective sliding motion of the SDW condensate with measuring the non-linear conductivity in this SDW phase. The measurement was done with dc and pulse methods. Below the SDW transition temperature T sDW, the sharp increase of conductivity from the ohmic one was observed with the clearly defined threshold electric field E T. This indicates the depinning of the SDW and the excess conductivity above E T is associated with the sliding motion of the SDW. The absolute value of E T is fairly larger than that observed in (TMTSF)2PF6, whose ground state is the incommensurate SDW at ambient pressure. With decreasing the temperature from T SDW, E T increases gradually and shows a relatively sharp drop after a peak around 03T SDW. This temperature is supposed to be connected with the sub-phase transition proposed from the temperature dependence of NMR relaxation rate. In addition, the excess conductivity normalized to the ohmic one, which corresponds to the current carried by the SDW condensate, shows a dip at 0.3T SDW with decreasing the temperature. In the dc I-V characteristics, the hysteretic behavior near E T appears only around 0.3T SDW. These behaviors suggest that the sliding mechanism of the SDW condensate varies across 0.3T SDW. We discuss the dynamics of the SDW in (TMTTF)2Br in comparison with that in (TMTSF)2X, considering the sub-phase transition. [Copyright &y& Elsevier]

Abstract: Highly conducting EMI-based room-temperature (RT) ionic liquids containing transition metals [EMI][M(III)Cl4] (M=Fe, Fe0.5Ga0.5 and Ga) were prepared, and their thermal and physical properties were well investigated, where EMI is l-ethyl-3-methylimidazolium, All the salts are liquid at RT and show a wide liquid range. High ionic conductivities (1.8-2.0x10−2 S cm−1 at 20°C) and low viscosities (12–14 cP at 30°C) are comparable to those of N(CN)2 and C(CN)3 salts. The FeCU and Fco.5Gao.5Cl4 melts exhibit a Curie-like behavior arising from the=5/2 spins on iron(III) ions, indicating the first conductive-paramagnetic biftinctional RT ionic liquids. On cooling, the solidified FeCl4 salt passes through an antiferromagnetic transition at 4.2K. On the basis of sixteen EMI-based RT ionic liquids including the present salts, it has become apparent that the conductivity is proportional to the reciprocal of the product of the anion weight and the viscosity. [Copyright &y& Elsevier]

Abstract: The quasi-one dimensional organic conductor (EDO-TTF)2PF6 shows the novel metal-insulator transition, which complies with the cooperative features of the tetramerization of EDO-TTF, the charge ordering of 0110 pattern, and the ordering of anion at ca. 280K. In this paper, the effect of the uniaxial strain on the metal-insulator transition of (EDO-TTF)2PF6 was investigated by means of the transport measurement. In low pressure region, the transport behavior was differently modified depending on the direction of the compression. In the cases that the strain was applied along the b and a′ axes within the donor layer (intralayer), the transition temperature (T MI) was slightly decreased or not changed and the jump of resistivity was suppressed with increasing the strain. Contrary, the T MI was enhanced remarkably to above 340K by the strain along the interlayer direction. The present results indicate that the strain along the interlayer direction is more effective for stabilization of insulating phase than those along the interlayer directions. It has been reported that the intralayer direction is expanded while the interlayer distance is shortened below T MI because the anion slightly inserts into the donor layer by means of the low temperature X-ray measurement at ambient pressure. The enhancement of the metal-insulator transition by the uniaxial strain along the interlayer direction is consistent with this anisotropic distortion of the unit cell through the transition. With applying the large strain along each direction, the insulating phase was suppressed and the metallic phase appeared around the room temperature. The metal-insulator transition occurred below about 200K with the feature of the second-order. [Copyright &y& Elsevier]

Abstract: The 1H and 13C NMR experiments of the Mott insulator κ-(ET)2Cu2(CN)3 with highly frustrated spin structure were performed under ambient and hydrostatic pressures. No indication of long-range antiferromagnetic ordering (moment, if any, &#60;0.01μB) was observed in the 1H NMR spectrum under ambient pressure, indicating the spin liquid state in the compound. The 13C NMR, a more sensitive probe of electron spins, showed field-dependent inhomogeneous broadening at low temperatures, which suggests the staggered magnetization partly induced by magnetic field. The Mott transition to Fermi liquid under hydrostatic pressure was observed in the resistivity and the 1H NMR spin-lattice relaxation rate. [Copyright &y& Elsevier]

The upper critical fields in the direction parallel to superconducting plane, Hc2″, of the layered salts κ-(BEDT-TTF)2X (X=Cu(NCS)2, Cu[N(CN)2]Br) and κ-(BEDT-TTF)4-Hg2.89Br8 far exceed the BCS Pauli paramagnetic limit and show variety of temperature (T) dependence at ambient pressure. We extended the studies of the Hc2″(T) diagrams for all main κ-(BEDT-TTF)2X superconductors by applying pressure. Emphasis is placed on the behaviour at low T and in high magnetic fields. The origin of the exceeding the BCS Pauli paramagnetic limit is discussed. The dependence of Hc2″ on the field direction within the plane is also presented. [Copyright &y& Elsevier]

Nine scenes of SPOT/HRV data obtained in eight different months in 1997 were evaluated for crop discrimination in the Saga Plains, Japan. All images were atmospherically corrected with the 6S code. Annual Normalized Difference Vegetation Index (NDVI) profiles were generated to characterize seasonal trends in six cropping systems (rice, rice-winter cereal, soybean, soybean-winter cereal, lotus, and rush). The dataset of this study showed the unique temporal change patterns of NDVI for each cropping system. Separability analyses determined optimal scene combinations for the highest accuracy in classifying the cropping systems. The scene combinations for the accurate classification of cropping systems were obtained from three separability measurements (Euclidean spectral distance, divergence, and Jeffries-Matsushita distance). Kappa statistics were applied to evaluate the classification accuracies. The four-scene combination that was derived from April, June, July and September classified the cropping systems almost as well as those combinations including more scenes. A colour composition technique applied to the three-scene combination that showed the highest separability also discriminated each cropping system. Based on these results, we can request observations during specific time intervals considering local crop calendars and environmental conditions. [ABSTRACT FROM AUTHOR]

The interface engineering of dibenzotetrathiafulvalene organic thin-film transistors (OTFTs) is reported. Polycrystalline-film morphologies are successfully controlled by surface treatments of silicon dioxide dielectric substrates using hexamethyldisilazane, a silane coupling agent, to tune the average lateral grain sizes between 0.2 and 20 μm. The field-effect mobility of the resulting OTFTs is approximately 0.55 cm2/V s. The effects of the grain sizes on subthreshold properties are discussed in terms of the charge transport against the grain boundaries through the films. [ABSTRACT FROM AUTHOR]

In this work the authors fabricated patterned thin films made of highly conductive organic charge-transfer complexes using the ink-jet printing technique. The overprinted films of BO9(C14-TCNQ)4 exhibit low sheet resistivity and are available for carrier injection and interconnection of organic field-effect transistors (FETs). The performance of pentacene thin film FETs, where the top contact and bottom contact are ink-jet-printed organic electrodes, demonstrates the potential of organic/organic heterointerfaces. [ABSTRACT FROM AUTHOR]

Fine control of p-, n-, and ambipolar-type field-effect transistor (FET) operations is successfully demonstrated in prototypical single-crystal organic FETs with use of chemically tunable nature of Fermi energy in tetrathiafulvalene-tetracyanoguinodimethane-based organic metal electrodes. Carrier-type preference and rectifying nature in the organic-organic contacts are revealed in terms of the FET operations as well as of the all-organic Schottky diode characteristics. [ABSTRACT FROM AUTHOR]

Abstract: We have performed a soft X-ray photoemission (PES) study of quasi-two-dimensional organic conductors BEDT-TTF (ET) and BEDO-TTF (BO) salts. We have clarified the difference in the electronic states between the bulk and surface insulating layers. The difference of the electronic states between ET and BO molecules is also found. On the other hand, the spectral weight in the vicinity of Fermi level is suppressed as reported by the low-energy PES. [Copyright &y& Elsevier]

A high mobility (∼1.0 cm2/V s) n-type organic field-effect transistor is devised in terms of the combination of semiconducting and metallic charge-transfer (CT) compounds, namely, DBTTF-TCNQ crystals as channels and TTF-TCNQ thin films as electrodes for carrier injections on top of the crystals. Comparison of the field-effect properties for devices with conventional electrode materials indicates the successful demonstration of the interface band engineering with use of the CT materials. [ABSTRACT FROM AUTHOR]

Cation radical salts based on BEDT-TTF (ET) with 1,1,2,4,5,5-hexacyano-3-azapentadienide (HCAPD−) and a series of 2-alkyl-1,1,3,3-tetracyanoallyl anions (R–TCA−; R=MeS, MeNH, NH2) were investigated. HCAPD− provided 1:1 (D:A) (1) and 2:1:0.5 (THF) (2) salts. Although 1 consists of ladder-like structures, the strong dimerization of ET⋅+ molecules results in a non-magnetic state. 2 shows a semiconductor–semiconductor transition near 200 K. Magnetic susceptibility of 2 shows a peculiar behavior. R–TCA− anions provided 2:1 salts. MeS– and MeNH–TCA− salts are metallic, though NH2–TCA− salt is regarded as a Mott insulator. [Copyright &y& Elsevier]

New ionic DA-type charge transfer solids of C70− were prepared with bis(benzene)chromium (Bz2Cr) and decamethylmetallocenes (Cp2&ast;M) (M=Ni, Cr). In the solid-state EPR spectra, no signals confirming C70− spins were detected below room temperature (RT), probably due to either an electronic or chemical dimerization. Above RT, a signal characteristic of a strong exchange coupling between donor cation and C70− spins gradually emerged for Bz2Cr complex, owing to the decoupling of the dimers. In dimethyl sulfoxide at RT, a signal characteristic of C70− spins was observed at g=2.0012–2.0014 with a narrow linewidth. [Copyright &y& Elsevier]

(EDO-TTF)2PF6 undergoes a first order metal-insulator transition at 280 K, which involves also magnetic susceptibility, crystal structure, distortion of molecular shape, and charge ordering. The effect of the phase transition on the electronic and vibrational spectra has been studied. [Copyright &y& Elsevier]

Novel tetrathiafulvalene (TTF) analogues, ethylenedioxy[2,4-dioxo(1H,3H)pyrimido]tetrathia-fulvalene, or ethylenedioxy[2-amino-4-oxo(3H)pyrimido]tetrathiafulvalene were synthesized. The crystal structure of the tetrabutylammonium (TBA) salt of deprotonated anion molecule of ethylenedioxy[2,4-dioxo(1H,3H)pyrimido]-TTF revealed complementary intermolecular hydrogen bonds leading to a homo-intermolecular dimer as building unit. Betainic radicals were prepared by oxidation the novel TTF analogues either electrically or chemically. The electric conductivity, magnetic and optical properties of mesomeric betaines are described. [Copyright &y& Elsevier]

First ionic multi-component complex CoTPP·2C60(CN)2·2Bz2Cr·3C6H4Cl2 (CoTPP: cobalt(II)tetraphenylporphyrin; Bz2Cr: bis(benzene)chromium; C6H4Cl2: o-dichlorobenzene) has been synthesized. CoTPP molecules and fullerides form channels providing the accommodation of Bz2Cr⋅+ and C6H4Cl2. For the first time it is shown that, in contrast to the neutral fullerenes, the cobalt atom of CoTPP coordinates to the fullerene anions with short Co···C(fullerene) distance of 2.28 A˚. CoTPP–C60(CN)2− anion is diamagnetic according to the EPR- and SQUID-measurements. The shape of the starting molecule retains at the formation of the C60(CN)2⋅− anion-radicals. The length of C&z.tbnd;N bonds are 1.143 and 1.161 A˚. [Copyright &y& Elsevier]

Infrared (IR) properties of κ-(ET-13C4)2Cu(CN)[N(CN)2] crystals in the normal (metallic) phase are reported. Deviations from conventional metallic properties are found and assigned to a strong electron correlation effect. [Copyright &y& Elsevier]

A reproducible current switching effect has been observed in various mixed-stack organic charge transfer crystals whose ionicities are close to the neutral-ionic phase boundary. This effect appears to be related to the intrinsic nonlinear conductivity, which has recently been reported in these crystals. This switching has a reasonably large delay time and our results indicate that it is a bulk property of the crystals. Discussion is given on the possible mechanism of this effect. [ABSTRACT FROM AUTHOR]

A case of biphasic type pulmonary blastoma in a 59-year-old man is reported. Although the tumour was radically resected, there was rapid metastasization to the neck, mediastinum, liver and multiple bones. Despite radiotherapy, the patient died about 14 months postoperatively. Close follow-up and aggressive chemotherapy should be considered for such tumours. [ABSTRACT FROM AUTHOR]