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To construct a long-term energy plan for renewable energies such as photovoltaics (PV), the influence of meteorological conditions on energy yield must be considered. It is necessary to understand how climate change impacts energy generation. For that purpose, a method to estimate PV energy generation considering climate change scenarios was developed. The developed method can estimate hourly generation amounts with spatial resolutions of 1-km mesh. It was applied to Fukushima Prefecture, located in the northeast region of Japan. To establish future scenarios three Representative Concentration Pathways (RCP) and seven Global Climate Models (GCM) were analyzed, and uncertainties caused by differences in future scenarios were investigated. The results show that annual generation of PV energy was estimated to increase on average by 1.7% in 2030, 3.9% in 2050, and 4.9% in 2070 due to climate change. Energy plans and adaptation actions are expected to be performed so the country is prepared for future impacts.

The objective of this study is to investigate potential diversified transportation energy source solutions and their effective use up to 2030 in order to establish sustainable energy use in road transportation. Five Association of Southeast Asian Nations (ASEAN) countries (Thailand, Indonesia, Malaysia, Philippines, and Vietnam) are examined by considering their economy, energy status, and automotive market scale. In this study, existing energy policies, fuel supply, demand status, petroleum and alternative fuel products, such as natural gas and biofuels, and oil refining/biofuels production capacity are investigated as components of energy mixing. If there are gaps between oil reduction targets and Business as Usual (BAU) consumption, or the required amount of biofuel use to achieve introduction target and possible supply, measures such as improved new vehicle fuel economy, adjustment of biofuel utilization, and natural gas utilization are considered to minimize gaps or to meet policy targets. An appropriate and cost-effective combination of measures is proposed as an alternative case for each country’s needs. Results show that biofuel utilization is one of the measures that is crucial in meeting policy targets. Even in the alternative case, however, estimated demand volume of biofuel exceeds domestic supply volume in some countries, while estimated demand volume of biofuel is lower than domestic supply volume in other countries. In order to solve these gaps and cultivate biofuel security within the ASEAN region, a concept of multi-national cooperation of biofuel is proposed. Creating policies to diminish barriers that prevent the trade of biofuels between neighboring countries is the key to success.

This study investigated the effects of the presence of a familiar pet dog on brain activity and psychophysiology in human volunteers. Fourteen participants (2 men, 12 women; mean age ± SD = 43.0 ± 10.8 years) were enrolled in the study. Uptake of 18F-2-fluoro-2-deoxyglucose ([18F]FDG) on whole-brain positron emission tomography (PET) scans in the presence (but without interaction) and absence of their own pet dog was analyzed. In addition, an electrocardiograph was recorded to assess heart rate variability. Psychological condition was determined using the Stress Response Scale-18 (SRS-18). PET brain images were analyzed and compared between the two conditions (t-tests; p < 0.001) using a statistical parametric mapping program (SPM-5). Deactivated brain areas were detected in the left middle frontal gyrus (Brodmann area: BA 8), the right fusiform gyrus (BA 20), the left putamen, and the thalamus in the presence of the pet dog, indicating reduced regional brain activities associated with stress perc...

The adsorption process, molecular arrangement and protonation behavior of self-assembled monolayers (SAMs) of bipyridine thiol on Au(1 1 1) were investigated using X-ray photoelectron spectroscopy (XPS) and scanning tunneling microscopy (STM), with a view towards constructing a molecular ion sensor. When the bipyridine SAMs were immersed in a strong CF 3 SO 3 H solution for protonation of the bipyridine group, additional N(1s) XPS peaks were generated at higher binding peak positions where the origin of the peak was considered to be the N–H species. We further investigated the relationship between the immersion time for the SAMs and the probability of protonation. We observed a decrease in the probability of protonation with a longer immersion time for the SAMs. We consider that both the bipyridine molecular arrangements and the molecular density on the Au surface are crucial for controlling the probability of protonation based on the STM and XPS data.

We investigated the use of a single treatment of estradiol benzoate (E2B) to prevent pregnancy in mismated dogs, including effects of dose, side effects, and mechanism of action. We used 74 female beagles aged 1-10 year. A single treatment of E2B (0.025, 0.05, 0.10, or 0.20 mg/kg; 10 dogs/dose) given 2 days after mating (5 days after ovulation) resulted in pregnancy rates of 70, 50, 10, and 0%, respectively, whereas pregnancy rate was 100% in 5 untreated (control) dogs. There were no side effects in dogs given E2B, regardless of dose. To clarify the mechanism of prevention of pregnancy, we investigated embryonic descent in the uterine tube and embryonic degeneration after treatment with 0.025 or 0.20 mg/kg of E2B; treatment delayed embryonic descent in the uterine tube and increased the incidence of embryonic degeneration. In conclusion, a single treatment of 0.020 mg/kg of E2B given 2 days after mating effectively and safely prevented pregnancy in dogs.

We describe a procedure for fabricating sub-5 nm gap junctions with sub-100 nm electrode-width using conventional photolithography. The fabrication procedure involves two photolithographic processes followed by shadow evaporation and electromigration. After lift-off following the second metal shadow evaporation, a nanoscale wire with a diameter less than 100 nm is fabricated along a sidewall of the second patterned photo-resist. The nanowire is cut by a milliamp current flow, then a sub-5 nm gap metal junction with a sub-100 nm electrode-width is fabricated. The temperature dependence of the conductance of the molecular wires that were bridging the junctions over the ultrasmall gap indicated a hopping conduction behaviour. The results demonstrate that these junctions can be used in the study of conductance measurements through molecular wires.

Surface potential switching on gold(111) surfaces is induced by complexation/decomplexation reactions of a bipyridine (BP) derivative and palladium(II) chloride, as observed by Kelvin probe force microscopy (KFM). On the basis of the theoretical predictions, a 4-(5-phenylethynyl-2,2'-bipyridine-5'-yl-ethynyl)benzenethiol (PhBP) derivative was synthesized and used as an active monolayer to catch transition metal ions. By using the microcontact printing (CP) technique, micron-size patterned PhBP monolayers, which act as effective hosts to coordinate palladium(II) chloride, were prepared on gold(111) surfaces. The KFM signal decreases by complexation of the Pd(II) chloride in PhBP monolayers and is recovered by removal of Pd ions using an ethylenediamine solution, as confirmed by X-ray photoelectron spectroscopy. This process is reversible, indicating that the surface potential switching is realized by complexation/decomplexation of Pd(II). A CP PhBP monolayer, when it detects the target palladium ion, shows sensitivity for the picomolar level detection judged from surface potential changes in KFM measurements. The dipole moment estimated by the surface potentials is much smaller than the calculated value, indicating that mechanisms for the reduction of the surface dipole moment exist in real monolayers prepared by the CP method.

We have developed a fabrication method for nanogap electrodes without employing photo- or electron-beam lithography to measure the electrical characteristics of nanostructured molecules. This angle-controlled shadow-masking method enables us to construct nanogap electrodes without a wet process after the molecules are positioned on the substrate. The proposed method makes it possible to measure electrical characteristics without structurally deforming or denaturing the molecules due either to the step edge of an electrode or to the organic solvents used in the wet process. The results demonstrate that a gap length between the electrodes of less than 100 nm can be fabricated reproducibly. We have measured the electrical characteristics of lambda DNA (λ-DNA) networks and molecular nanorods made of porphyrin-derivative molecules (TPPS: 5,10,15,20-tetraphenyl-21H,23H-porphyrine tetrasulfonic acid) in which J-aggregates are formed inside. Experimental findings reveal that the electrical conductivity of λ-DNA decreased under a vacuum condition, whereas that of TPPS nanorods decreased under oxygen and nitrogen gas-purged conditions.

Carbon nanotube (CNT) devices have been constructed by a post-synthesis alignment, due to difficulties to form a CNT directly on a substrate, whereas CNTs have been found to grow by irradiating an electron beam onto polyyne-containing carbon. This technique is a candidate to construct a CNT device without a metal catalyst by highly geometrically resolvable electron beam lithography. Two types of polyyne-containing carbon (well-aligned and amorphous) are observed and compared by a transmission electron microscope (TEM), providing insights on the formation mechanism and requirements for the precursor. The results suggest that a substantially aligned and not-condensed morphology is essential to form CNTs.

All-trans oligo(para-phenylenevinylene) (OPV) methyl thiols of a two-ring phenylene-vinylene dimer and a three-ring trimer have been synthesized to prepare self-assembled monolayers (SMS) onto an Au(1 1 1) surface. The molecular level morphologies of the monolayers prepared on Au surfaces were probed by scanning tunneling microscopy (STM) or atomic force microscopy (AFM). The soluble dimer formed a highly ordered structure lying down on the Au surfaces. The molecules of trimer stand slantwise on the Au surfaces, but the structure of monolayers is less ordered. Another longer OPV methyl thioacetate, a slightly soluble four-ring tetramer, has also been synthesized. Although it was difficult for aggregative molecules of the longer OPV to self-assemble on Au, we could successfully insert the tetramer into tetradecane-1-thiol monolayers on Au surfaces by an exchange reaction. The mixture monolayer showed that the isolated tetramer was adsorbed almost vertically on the Au surfaces.

Microcontact printing (μCP) is the first soft-lithographic technique developed by Kumar and Whitesides in 1993. At first, it was mainly used to pattern thiol self-assembled monolayers on metal surfaces, but later on, has been applied to various materials, including biological molecules. Because of its wide application, the μCP is considered to be not only a patterning technique, but also used as a convenient soft-manufacturing method. In this article, basics and recent topics of the μCP are overviewed. Main technical developments are targeting on the biological applications and the fabrication of organic transistors. We introduce up-to-date technical achievements of the both fields. In addition, efforts to scale down the pattern resolution and unique applications utilizing the properties of the stamp material are mentioned.

The electrical conduction of self-assembled monolayers (SAMs) made from conjugated molecules was measured using conductive probe atomic force microscopy (CP-AFM), with a focus on the molecular structural effect on conduction. First, the electrical conduction of SAMs made from phenylene oligomer SAMs was measured. The resistances through the monolayers increased exponentially with an increase in molecular length and the decay constants of transconductance beta were about 0.45 to 0.61 A(-1) measured at lower bias region. We further investigated the influence of applied load on the resistances. The resistances through terphenyl SAMs increased with an increase in the applied load up to 14 nN. Second, using an insertion technique into insulating alkanethiol SAMs, the electrical conduction of single conjugated terphenyl methanethiol and oligo(para-phenylenevinylene) (OPV) molecules embedded into insulating alkanethiol SAMs were measured. Electrical currents through these single molecules of OPVs were estimated to be larger than those through single terphenyl molecules, suggesting that the OPV structure can increase the electrical conduction of single molecules. Third, apparent negative differential resistance (NDR) was observed at higher bias measurements of SAMs. The appearance of NDR might be related to roughness of SAM surface, because apparent NDR was often observed on rough surfaces. In any case, the tip-molecule contact condition strongly affected carrier transport through metal tip/SAM/metal junction.

We are investigating electrical properties of multiwalled carbon nanotube (CNT) probes for scanning tunneling microscopy (STM). To improve the electrical conduction and reduce the contamination at the interface to the gold base, we selected conductive CNTs and heated the base and CNT during the CNT attaching process. Before STM measurements, the probes were cleaned by annealing in vacuum for 4–8 h. With these treatments, we found a small number of tips exhibiting linear metallic current–voltage (I–V) curves on Au(111), while all the CNT tips attached on gold (not heated) exhibited nonlinear I–V curves. We discuss the possibility that the metallic behavior of the CNT probes may be caused by the diffused gold atoms along the CNT surfaces by the long heat treatment.

Oligo(para-phenylene-vinylene)-methanethiol of trimer and dimer have been synthesized to prepare monolayers onto Au(111). The trimer diluted in dichloromethane glows with a brilliant blue fluorescence when excited with UV light (365 nm). The absorption and emission spectra of the dimer diluted in CH 2 Cl 2 show a blue shift. The molecular level morphologies of the monolayers prepared on gold surfaces were probed by scanning tunneling microscopy or atomic force microscopy (AFM). The dimer is entire trans isomer, which formed highly ordered self-assembled monolayers (SAMs) on Au. The trimer is a mixture of cis–trans isomers, and did not form ordered monolayers on Au. However, the trimer molecules could be embedded in dodecanethiol SAM, and showed higher conductance than oligo(para-phenylene) molecules characterized using a conductive AFM.

Polyyne-containing carbon has been shown to be converted to carbon nanotubes (CNTs) and carbon onions by irradiating an electron beam. The carbon, which is prepared by a reduction of poly(tetrafluoroethylene) (PTFE), is unstable, reactive, and it is used as a precursor to form carbon nanostructrues. A precise transmission-electron-microscope (TEM) observation reveals that some nanostructures, fibrous and spherical, are already formed in the carbon before the irradiation. The nanostructures are assumed to be formed during the reduction of PTFE. The spherical carbon is well graphitized, whereas the fibrous is not. The reduction is carried out at 0 °C, which is not enough for the fibrous carbon to be well graphitized. The findings suggest a possibility to form a CNT without an electron beam via a reactive polyyne precursor, and are expected to lead an as-designed CNT synthesis.

We studied field-induced conductance change of thin organic films using the trench-type electrodes, where the gate field is applied from the sidewall of the trench. We fabricated the electrodes, and observed field effects of a conductive self-assembled film and oligothiophene thin films. The electric field generated by the electrode structure was calculated by a two-dimensional finite element method. The gate field strength becomes weaker as the film thickness is reduced, while the fields generated by the source–drain potential increase. This result denies the `normally-off' characteristics since a small source–drain voltage between the nano-gap could cause the conductance change corresponding to the large gate voltage. Although three-dimensional structures or interface roughness could enhance the effective gate fields, we speculated that the self-assembled film showing the field effects was not a monolayer, but most probably multilayers or mounds of aggregated molecules of more than 10 nm thickness.

An unusual penta-peptide nanotube was synthesized by a solid-phase method using Fmoc chemistry. This nanotube consists of the natural homo-L-amino acid sequence (cyclo[-(L-Gln)5]), which is different from the already-known dl-peptide nanotubes having an even number of residues. We also observed the morphology by atomic force microscope (AFM) and found meandering tubular structures on the substrate. This result is consistent with our ab initio energy calculations, which show that the penta-peptide nanorings stabilize by breaking the C5 symmetry and stack themselves to form a meandering nanotube through the inter-ring hydrogen bonds.

Rotaxane (R4) molecules coupled with a lipoic acid moiety, which contains a disulfide group, have been fixed on evaporated Au films. R4 molecules have been coadsorbed with n-hexanethiol (C6SH) from solutions of methylene chloride to form self-assembled monolayers (SAMs). X-ray photoelectron spectroscopy reveals that two-component SAMs were rapidly formed within 1 h, while further immersion of more than 1 h caused a gradual decrease in the amount of R4 molecules in the mixed SAMs. This observation indicates that the R4 mole fraction in SAMs (Χ S A M ) was primarily governed by the adsorption kinetics of both R4 and C6SH. Then we attempted to control Χ S A M of the mixed SAMs by changing the R4 mole fraction of the solutes in solution (Χ s o l ). Infrared spectroscopy and tapping-mode atomic force microscopy (TM-AFM) were conducted to estimate the Χ S A M values of the two-component SAMs. We compare the experimental relations between Χ s o l and Χ S A M with model functions in connection with the adsorption kinetics. One of the models, in which desorption of C6SH species obeys second-order kinetics, well describes the experimental results in a wide domain (10 - 7 ≤ Χ s o l ≤ 1). This agreement between the model and the experimental results suggests that adsorbed C6SH can be desorbed as disulfide and that protrusions observed by TM-AFM are most likely isolated single R4 molecules.

We demonstrate a high yield production scheme to fabricate sub-10 nm co-planar metal-insulator-metal junctions without using electron beam lithography. The fabricating procedure contains two photolithographys followed by shadow evaporation. Ultrasmall gaps were formed in the crossing region of the two metal layers during the evaporation of the second layer. The sizes of the gaps were estimated using scanning electron microscopy images. Poly (3-hexylthiophene-2,5-diyl) layers were deposited on the junctions using a special ink-jet technique. The results of the conductivity measurement of the molecular layer indicate that these junctions can be used in the study of molecular sensors.

Carbon nanotubes (CNTs) have attracted much attention for their unique properties, although their formation mechanism is not well understood. The authors have been studying a technique to form CNTs by an electron beam that is carried out in a transmission electron microscope (TEM) and is compatible with in situ and real-time observation of the growth. The observation, where a precursor (polyyne-containing carbon) is heated and irradiated by an electron beam, shows that the growth occurs in two steps: rapid formation of rodlike carbon (first step) and slow graphitization of its wall (second step). The hollow inside the CNT is not formed in the first step and develops during the second. The formation mechanism is discussed in relation to in situ observations.

Polyyne-containing carbons are transformed to multi-wall carbon nanotubes (CNTs) in a transmission electron microscope. This technique has an advantage to observe the CNT growth in an in-situ way, and the CNTs have been found to grow in a two-step process: quick formation (a few seconds) of rod-like carbons, and slow formation (1 min) of the hollows inside the rods accompanied by graphitization of the walls. The technique has a possibility to be applied to fabricate CNT devices. Thus the growth conditions (heating temperature and its duration) were investigated and are discussed in this paper. The heating duration affects the number of graphene layers of the wall, while the temperature does not affect the length, the diameter, and the number of graphene layers. The longer heating duration, which corresponds to less supply of the precursor due to its evaporation in vacuum, leads to thinner walls and more round-shaped caps. This finding corresponds to the formation mechanism, i.e. growth from the bottom in a solid phase, which has been assumed for this technique.

The electrical conduction of self-assembled monolayers (SAMs) made from conjugated molecules was measured using conductive atomic force microscopy (AFM), with a focus on the molecular structural ef...

The mechanism of the carbon nanotube (CNT) formation and its graphitization has not been well understood and is still under controversy. The authors have been studying a new process to form CNTs, where polyyne-containing carbons are heated and irradiated by an electron beam in a transmission electron microscope (TEM). The technique is compatible to an in-situ observation and was applied to a high-resolution TEM (HRTEM) to elucidate the graphitization mechanism. The observation shows that micro-graphenes exist from the beginning of the formation process and develop to form highly ordered graphene layers through fusion and rearrangement of the premature layers, accompanied by evaporation of micro-graphenes. The CNT formation mechanism focusing on its graphitization is presented and discussed.

A new way to form carbon nanotubes (CNTs), carbon nanocapsules (CNCs), and carbon nanoparticles (CNPs), where polyyne-containing carbons are heated and irradiated by an electron beam in a transmission electron microscope (TEM), has been developed. The technique was applied to carry out an in-situ observation of those formation processes. Though the CNPs have been reported to be formed accompanied by the CNTs, the CNPs and the CNCs were found to be formed independently from the CNTs. The CNTs are preferentially inside of the polyyne-containing carbon films, while the CNPs/CNCs are outside of the films. The difference of the inside and the outside are discussed to lead to understanding of the CNC and CNP formation process. From the in-situ observation, the existence of metal particles, the high surface energy, the high wettability, and the high viscosity of the polyyne-containing carbons are assumed to be relevant to the preferential formation of CNCs/CNPs to CNTs.

We investigated an annealing effect of self-assembled monolayers (SAMs) generated from derivatives of terphenylmethanethiols and tetradecanethiol (C14) on Au(111) using scanning tunneling microscopy (STM), X-ray photoelectron spectroscopy, and contact angle measurement. STM data revealed that the molecules were partially desorbed by the annealing process at temperatures where the contact angle of the hexadecane began to decrease. The decreases in contact angles of both the CF3- and CH3-terminated terphenyl SAMs were caused by annealing at 180 °C for 1 h, while a similar decrease began at a lower temperature of 150 °C in the C14 SAMs. From the STM data, a large amount of CH3-terminated terphenyl molecules remained after annealing at 180 °C for 3 h, while a small amount of molecules were observed in the other two SAMs. These data demonstrate that the CH3-terphenyl-derivatized thiol SAM had the highest thermal stability of the three SAMs, and the molecular backbone structure and end group were crucial for de...

Barrier height of self-assembled monolayers (SAMs) on Au(111) was measured using scanning tunneling microscopy (STM) with a vertical modulation. We obtained nanometer scale STM images of alkanethiol SAMs, and binary component SAM films fabricated by an implantation technique. Local barrier height on the alkanethiol SAM at the depressions and the domain boundaries is larger than that on the domains where the molecular lattice is visible, probably due to the molecular density or orientation. A molecular resolution contrast was obtained at a conjugated molecule embedded in the alkanethiol SAM, reflecting the difference in the molecular species. We found that the tip-sample interaction force affects the barrier height measurements, especially when the tunneling gap is small, e.g., on nonanethiol SAM at the tunneling resistance smaller than 50 GΩ.

We have investigated an insertion process of conjugated molecules, 4-biphenylmethanethiol (BP) and [1,1′:4′,1″-terphenyl]-4-methanethiol (TP) into preassembled n-alkanethiol self-assembled monolayers on Au(111) using scanning tunneling microscopy (STM). Ex situ STM observation revealed that the insertion process is dependent on an organic solvent in which the conjugated molecules dissolve. The insertion of conjugated molecules with three phenyl rings (TP) was faster than that with two phenyl rings (BP). By analyzing the STM images, the lower limits of resistances for single BP and TP molecules were obtained as 22±5 and 36±5 GΩ, respectively.

We have studied the phase-separation of self-assembled monolayers (SAMs) of dialkyl disulfides on Au surface. Initially, the heat-induced phase-separation of SAMs consisting of unsymmetric disulfide molecules (CF 3 (CF 2 ) 5 (CH 2 ) 2 SS(CH 2 ) 7 CH 3 ) of hydrocarbon and fluorocarbon chains was investigated. We proved that the dimer structure cleaved on the Au surface. Subsequently, we formed one-dimensional nanostructures utilizing an anisotropic phase-separation of SAMs consisting of a mixture of the above unsymmetric disulfide and a symmetric disulfide of hydrocarbon (CH 3 (CH 2 ) 7 SS(CH 2 ) 7 CH 3 ). The wire-like structure with a width of 5 nm and a length ≈100 nm was observed by scanning tunneling microscopy.

We have used high-resolution X-ray photoelectron spectroscopy (XPS) to investigate the molecular dependence on sulfur chemical states of organosulfur monolayers of alkanethiol, dialkyl disulfide, m...

We synthesized soluble rod-like silylthiophene, silylbithiophene, and silylquaterthiophene derivatives with various functional groups. Their self-assembled monolayer films on silicon oxide were evaluated by atomic force microscopy, X-ray photoelectron spectroscopy, water contact angle measurements, and fourier transform infrared-reflection absorption spectroscopy. We found that the molecular density (molecules/area) of the resultant films increased with thiophene moiety. This is probably due to the effective π-stacking of aromatic rings between molecules.

We have succeeded in the formation of one-dimensional wire-like structure in the self-assembled monolayers (SAMs) made from the mixture of an unsymmetric disulfide consisting of hydrocarbon and fluorocarbon chains and a symmetric disulfide of hydrocarbon chains on Au(111). By focusing on co-adsorption process of the above two disulfide molecules onto the Au surface, it is found that an exchange reaction should take place and a part of the symmetric disulfide molecules was replaced by the unsymmetric disulfides during immersion in the solution. The molecules having fluorocarbons were also found to replace hydrocarbons on Au surface.

The formation process of an alkylsiloxane self-assembled monolayer (SAM) on silicon oxide produced under various conditions was investigated. The growth rate of octadecyltrichlorosilane (OTS) SAM was dependent on the moisture level in the oxidation system. Area-selective oxidation of a silicon substrate with a native oxide layer was carried out under controlled humidity conditions by the field induced oxidation (FIO) technique using an atomic force microscope with a conductive cantilever. The silicon substrate partly FIO oxidized under dry nitrogen was immersed into the OTS solution, and the contact angle and topographic image showed that the OTS layer was formed only on the native oxide. In contrast, when the FIO was performed under a humidity of 88%, OTS SAM was formed both on FIO and native oxides. These results indicate that SAM formation on silicon oxides can be locally suppressed by FIO in a dry environment. Using this technique, we could fabricate an OTS SAM line structure as narrow as 22 nm.

Phenylene ethynylene dithiol derivatives containing a bipyridine ligand along the conjugated system were introduced between nanogap electrodes, and significant conductance changes of the bridging molecules were observed upon complexation with Pd(II).

Alkanethiol self-assembled monolayers (SAMs) on Au(111) deposited in a vacuum were studied on the nanometer scale using a scanning tunneling microscope (STM). After about 17 h from the gas dose of 4200-6000 langmuirs nonanethiol, two-dimensional crystallized domains were observed. The areas covered with the molecules and the bare gold surface were identified by topography, current-voltage characteristics, and the threshold voltage required to modify the surface. By applying 2.6-3.0 V to the sample, we could extract molecules and create holes with diameters of 2-5 nm in the SAM film. Applying 14 voltage pulses of 2.6 V to a 10 nm diameter circle on the sample locally removed the SAM film. We could then observe the dynamic formation process of the SAM film with molecular resolution using the STM, and within 5 min, the removed area was seen to be almost recovered with the molecular lattice except for a small number of incurable defects. Since the recovered area looked identical to the pristine film, we concluded that the molecules can be locally extracted without causing damage to the gold substrate under this condition.

We have studied phase-separation and patterning of self-assembled monolayers (SAMs) on Au(111). In this study, we used an ethanol solution of mixed unsymmetric disulfide with hydrocarbon and fluorocarbon chains [CF3(CF2)5(CH2)2S–S(CH2)7CH3], and a symmetric disulfide of hydrocarbon chains [CH3(CH2)7S–S(CH2)7CH3], to derive the SAMs. Then we obtained a wire-like structure with a width of 5 nm extending to about 100 nm in these SAMs after they were annealed at 100°C for 8 h. The formation of nanowires indicated that anisotropic nucleation of hydrocarbon parts along the [112] direction of the Au surface occurred.

Phase-separation of self-assembled monolayer (SAM) made from binary components is studied. The interaction between the molecules in the SAM films was estimated by a simple Monte Carlo simulation. The molecules are arranged on the two-dimensional triangular lattice sites and exchange their position with the probability determined from the molecular interaction energy calculated over the fifth nearest neighbors. One-to-one mixture with lattice sizes of 128×128, 256×256, and 512×512 was calculated, and the threshold energy for the domain formation was independent of the size. On the other hand, the domain shape and size depended on the calculation method and the lattice size. The threshold energy at 300 K corresponds to the estimated interaction between the hydrocarbon chains of 7–8 carbon atoms.

Following the proposal of a new structural model by Fenter et al. (Science 1994, 266, 1216), several reports have indicated the existence of dimers in a self-assembled monolayer (SAM) film on Au (1...

Atomic force microscopy has been successfully used to observe morphologies and characterize polymer components of poly(styrene-block-ethylene/butylene-block-styrene) (SEBS) triblock copolymer surfaces. The surfaces exhibited characteristic topographies consisting of hills and valleys. The height difference between them increased with the polystyrene component, which is probably due to the stress increase between two phases. The surface area fraction of the hills also increased with polystyrene component, and the local stiffness of the hills was higher than that of the valleys. These results indicate that the hills correspond to polystyrene and the valleys to rubbery poly(ethylene/butylene). The morphology of polystyrene changed from long worm-like to mesh-like structures with increasing polystyrene content in the block copolymers and exhibited a moniliform-like structure with a periodicity of 20–30 nm. These structures may be caused by surface segregation of the polystyrene component in the block copolymer surface.

For more than a decade, numerous disputes over medical errors and other safety issues in the healthcare system have occurred and attracted growing interest from society. As a result, through the Model Project for the Investigation of Death Associated with Medical Practice, the Outline Proposal of the Measure to Establish an Investigative Commission on Medical Accidents was proposed by the Japanese Ministry of Health, Labour and Welfare. However, this measure was not finalized. The course of the controversies involved has various implications. The Project Committee of the Japan Medical Association proposed the fundamental viewpoints to establish an exploratory system for medical accidents and to change the stressful medical environment for both physicians and patients based on the principle of the occupational autonomy of physicians.