Search

In bending process of sheet materials, a springback is remarkable due to the residual stress generated inside of the material, which greatly affects the product accuracy. In order to suppress the springback, the rubber-assisted stretch bending method, which bending process is performed with applying a tensile force in the longitudinal direction of a sheet material has been proposed. We propose the optimum arrangement of the two kinds of rubbers for the “rubber-assisted stretch bending method” for the uniform bending with a constant curvature radius. The optimum tensile stress is realized by each frictional force between the individual rubber and specimen. And since the rubber is partially affixed to the dies, the bending deformation is carried out by the metal surface of the die material, improvement of shape accuracy can be expected. The upper and lower dies are divided into three division on the surface, and the two elastic rubbers are placed on each part on the bending surface of the die. The springback was decreased to 17% in comparison with simple bending using ordinary metal dies by the optimum arrangement of rubber layout.

We measured the spontaneous strain c/a-1 of the antiferrodistortive phase transition in the conductive strontium titanates SrTi1-xNbxO3 with x = 0, 0.01, 0.02 and SrTiO3-δ by means of synchrotron X...

We have studied the relation between crystal structures and growth condition of molecular beam epitaxy (MBE) grown In 2 Se 3 on GaAs (0 0 1) substrates over a wide growth temperature range from 250 to 550 °C and VI/III ratio range from 0.006 to 195. It is confirmed that α -In 2 Se 3 crystals were grown at a high VI/III ratio larger than about 1.0 and γ -In 2 Se 3 crystals were grown at a low VI/III ratio between about 0.01–0.1 by X-ray diffraction and Raman scattering measurements. It is also found that the γ -In 2 Se 3 was even grown at a low temperature of 250 °C. Exciton emissions were clearly observed in the γ -In 2 Se 3 films grown at 350 °C. This indicates the grown films have a good crystalline quality.

We observed resonant coherent excitation (RCE) of 1s electron to the n = 2 states in 390 MeV/u Ar 17+ ions passing through thin Si crystals of about 1 μm in the {2 2 0} planar-channeling condition by measuring both the exit charge state and the exit angle of the emerged ions simultaneously in a list mode. The yield of the de-excitation X-rays from the Ar 17+ ions was also measured. The thin crystal is suitable to study trajectory dependent RCE dynamics, because the exit angle of the high energy planar-channeling ion is uniquely related to the ion trajectory. From the de-excitation X-ray yield on resonance, we learned that RCE occurs with a fairly large probability within the traveling length of about 1 μm, and a majority of the excited ions survive from ionization by the collisions with target electrons or nuclei, and de-excite into the ground state by emitting the X-rays. On the other hand, the observed resonance profile of the exit charge state is shallow and broadened by the Stark effect. We found that the ionization of the excited ions takes place when the ions travel close to the atomic plane from the observed relation between the charge state and the exit angle of the emerged ions.

We investigated resonant coherent excitation of H-like Ar17+ and He-like Ar16+ ions planar channeled in a Si crystal under the V-type and ladder-type double resonance conditions. In both cases, we observed distinct enhancement in the ionized fraction of the transmitted ions when the double resonance conditions were satis.ed. In the ladder-type configuration, the enhancement indicates that the doubly-excited 2p2 state of He-like Ar16+was produced through doubly-resonant coherent excitation.

Aims : To determine the prevalence of hepatitis C virus (HCV) infection in B-cell lymphoma in Japan. HCV infection and type II (monoclonal IgM) cryoglobulinaemia (CG) may be involved in the pathogenesis of low-grade B-cell lymphoma (ML) in southern Europe. Methods and results : Forty-five (11.3%) of 400 B-cell ML cases were HCV antibody (Ab) positive, which was significantly (P

X-rays emitted from Ar 17+ , Fe 24+ and Kr 35+ ions of about 400 MeV/u transmitting through a thin Si crystal of about 20 μm thickness have been measured in a planar channeling condition and compared with those in a random incident condition. We have found that the X-ray yield from Ar 17+ ions is larger for the channeling condition than for the random incidence, while those from Fe 24+ and Kr 35+ ions are rather smaller. Such tendencies are explained by considering the projectile dependences of excitation and ionization probabilities together with X-ray emission rates. A crude simulation has qualitatively reproduced these experimental results. When the crystal thickness is small, the X-ray yield is smaller in the channeling condition than in the random incident condition, because excitation is depressed. However, for thicker crystals, the X-ray yield is larger, since the survived population of projectile-bound electrons is larger due to small ionization probabilities under the channeling condition. This inversion occurs at a specific crystal thickness depending on projectile species. Whether the thickness of the used crystal is smaller or larger than the inversion thickness determines enhancement or depression of the X-ray yield in the channeling condition.

We have performed powder X-ray diffraction of MgB2 superconductor between 10 and 300 K. Temperature dependence of integrated intensities of both (002) and (110) X-ray reflections shows a peak at around TC, superconducting transition temperature. The integrated intensity of the X-ray reflection is related to the phonon frequency through a Debye--Waller factor. Lattice parameters a and c show negative thermal expansions at low temperatures. The negative thermal expansion might be due to an electronic origin and not directly related to the superconducting transition.

Bronchogenic cysts are rare congenital anomalies of the primitive foregut that are usually found above the diaphragm, and a retroperitoneal location is extremely unusual. Due to the low prevalence of these pathologies, their imaging features have seldom been described. We report a rare case of retroperitoneal bronchogenic cyst showing characteristic imaging features of milk of calcium on plain abdominal radiography and computed tomography.

X-rays emitted from resonant coherently excited (RCE) n =2 states of 390 MeV/amu hydrogen-like Ar 17+ ions were observed under planar channeling in a Si crystal. The resonance profiles for X-ray emission consisting of two peaks for j =1/2 and j =3/2 are characterized by suppression of the j =1/2 peak. The degeneracy of the n =2 states are removed by Stark effect due to the static crystal field. The RCE probability of these Stark splitted substates differs, reflecting the polarization of the oscillating crystal field. However, the associated alignment was not clearly observed. It is explained by the fact that both polarization of the oscillating crystal field and the wave functions of Stark-mixed n =2 states depend on the distance from the channel center, and the X-ray emission is preferred in a channel center in a crystal.

Spontaneous occurrence of spinal subdural haematoma (SSH) is very rare. While many neurological disorders can develop in pregnant patients in relation to haemostatic imbalance, there have been no reports in the literature suggesting that pregnancy and/or childbirth per se could be a single risk factor for acute SSH. A 38-year-old previously healthy woman gave birth to a baby via transvaginal normal delivery. The patient had no history of receiving anticoagulants. Eight days after delivery, she experienced sudden onset severe interscapular back pain, and the next day she developed dysesthesia in the both legs and mild urinary retention. Severe meningeal signs were noted. Lumbar puncture revealed bloody cerebrospinal fluid. Magnetic resonance images revealed SSH in the ventral position spreading from levels Th1 to Th7. The patient underwent conservative treatment after which the symptoms gradually improved. Serial MRI study at 17 and 69 days after onset showed spontaneous regression of the SSH. Spinal angiography did not show any vascular malformations, but simultaneous cerebral angiography revealed a co-existing cerebral aneurysm on the C2 segment of the left internal carotid artery. It is unlikely that the cerebral aneurysm was the origin of the SSH, based on the clinical and radiographic findings. Moreover, we confirmed the unruptured nature of the aneurysm during the clipping procedure at open surgery. We report the unique case of subacute SSH occurring 8 days after childbirth without other known risk factors. The possible etiology and magnetic resonance imaging (MRI) findings in this case, and the current controversy concerning therapy for SSH are discussed.

Molecular dynamics simulations in fluids and supercooled fluids of a two dimensional system have been carried out. The effect of the system size has been checked by comparing the smaller size system (10,000 atoms) with the larger size system (250,000 atoms). The shapes of the regions showing the (linearly) correlated motion of atoms are very similar regardless of size. The fractal dimension is about 1.5 dimension which has been calculated in the 2-D binary mixture of supercooled fluids. The regions of this motion spread widely for the larger system, especially in the highly supercooled fluids and glasses.

The critical current density, J/sub c/, in high-temperature superconductors becomes zero at irreversibility field, B/sub irr/, appreciably lower than the upper critical fields, B/sub c2/. The enhancement of J/sub c/ and B/sub irr/ is one of the crucial subjects to be attained. In high-temperature superconductors, conclusive result has not yet been presented because of the complexity of the material structure and in low-temperature superconductors scientific interest has not been paid because of the vanishingly small deviation of B/sub irr/ from B/sub c2/. In this study, we'll apply a simple system of low-temperature superconductor Pb-Bi, whose pinning characteristics were fully examined and controllable, to understand the relation of B/sub irr/ and the pinning mechanism. Observed irreversibility field, B/sub irr/, is discussed using the pinning characteristics and numerical calculation based on the flux creep theory. Magnetic relaxation caused by the flux creep was also observed by SQUID magnetometer. The relation of the apparent pinning potentials, U*/sub 0/, estimated from the flux creep rate and the irreversibility field, B/sub irr/, are studied.

In this communication we describe a titanium alloy material that has an excellent low outgassing property whose rate is lower than 6×10−13 Pa m s−1. This value is much lower than that of standard vacuum materials by three orders of magnitude under the same ordinary pretreatments. In our titanium alloy a natural TiO2 thin layer on the surface acts as an enhanced diffusion channel for dissolved gases, mainly hydrogen, consequently very quick evacuation of gas near the surface gives a very low outgassing rate.

Inflammatory pseudotumor of the liver is a localized mass consisting of a fibrous stroma and chronic inflammatory infiltrate without anaplasia. Diagnosis of this rare disease is important to avoid surgery. The purpose of this study was to determine if CT is useful in the diagnosis of this lesion.CT scans of nine patients with a proved diagnosis of inflammatory pseudotumor of the liver were reviewed. Diagnosis was made by the surgical resection in three patients and by percutaneous biopsy in six patients. Six patients had symptoms and laboratory data suggesting active inflammation caused by the pseudotumor. The remaining three patients were asymptomatic. CT scans were performed with IV administration of the contrast material; scans were obtained in the portal venous and delayed phases in six patients and in the delayed phase in three patients. CT scans were analyzed for the number and size of the hepatic masses, and the degree and pattern of contrast enhancement on portal venous phase and delayed-phase images.Eight patients had a solitary hepatic mass, and one patient had two masses on the CT scan. The average size of the masses in the symptomatic patients (8.3 cm) was larger than that in the asymptomatic group (3.6 cm). CT scans in the portal venous phase showed a variable degree of contrast enhancement (seven masses). At least a part of seven masses, six of which were in symptomatic patients, showed greater contrast enhancement on delayed-phase CT scans than on the normal liver parenchyma. No constant pattern of enhancement was observed on delayed-phase CT scans in asymptomatic patients.Inflammatory pseudotumor of the liver should be included in a differential diagnosis in patients with a hepatic mass on a CT scan, especially when patients are symptomatic and the mass is fairly large and solitary showing contrast enhancement greater than that of liver parenchyma on delayed-phase CT scans. Percutaneous biopsy should be performed to obtain a histologic confirmation.

In the light of the tremendous progress that has been made in raising the transition temperature of the copper oxide superconductors (for a review, see ref. 1), it is natural to wonder how high the transition temperature, Tc, can be pushed in other classes of materials. At present, the highest reported values of Tc for non-copper-oxide bulk superconductivity are 33 K in electron-doped CsxRbyC60 (ref. 2), and 30 K in Ba1-xKxBiO3 (ref. 3). (Hole-doped C60 was recently found4 to be superconducting with a Tc as high as 52 K, although the nature of the experiment meant that the supercurrents were confined to the surface of the C60 crystal, rather than probing the bulk.) Here we report the discovery of bulk superconductivity in magnesium diboride, MgB2. Magnetization and resistivity measurements establish a transition temperature of 39 K, which we believe to be the highest yet determined for a non-copper-oxide bulk superconductor.

International audience; We measured kinetic energies of the fragment ions of argon dimers multiply ionized by low-energy Ar9+ collisions. For (Ar2)4+ dissociation, the asymmetric channel (Ar3+ + Ar+) yield is found unexpectedly higher than the symmetric channel (Ar2+ + Ar2+) yield in contrast with previous observation for covalent molecules or clusters. For the dissociation channel (Ar2)2+ → Ar+ + Ar+, two wellseparated peaks were observed, clearly evidencing that the direct Coulombic dissociation and the radiative charge transfer followed by ionic dissociation alternatively occur for the dicationic dimers. The respective intensity of these two peaks provides a direct mean to unravel the respective proportion of one-site and two-site double-electron capture, which are found equal for this collision system.

Expérience GANIL/ARIBE; International audience; Low-energy collision experiments of an argon dimer with Ar(9+) were performed to measure branching ratios and kinetic energy release (KER) distributions for multiply ionized dimers. Two well-separated KER peaks are observed at 3.8 and 5.3 eV for the doubly ionized dimers, and are assigned to direct Coulombic dissociation and radiative electron capture followed by ionic dissociation, respectively. For the dissociation channels Ar(2+) + Ar(+), Ar(3+) + Ar(+) and Ar(2+) + Ar(2+), the KER distributions show a single peak, the positions of which agree well with those expected for Coulombic dissociation. The branching ratio of asymmetric charge sharing, Ar(3+) + Ar(+), is larger than that of symmetric charge sharing, Ar(2+) + Ar(2+). These results represent unambiguous evidence of a strong limitation of charge mobility across the Ar dimer.

We report growth and characterization of heavily boron-doped 3C-SiC and 6H-SiC and Al-doped 3C-SiC. Both 3C-SiC:B and 6H-SiC:B reveal type-I superconductivity with a critical temperature Tc=1.5 K. On the other hand, Al-doped 3C-SiC (3C-SiC:Al) shows type-II superconductivity with Tc=1.4 K. Both SiC:Al and SiC:B exhibit zero resistivity and diamagnetic susceptibility below Tc with effective hole-carrier concentration n higher than 1020 cm−3. We interpret the different superconducting behavior in carrier-doped p-type semiconductors SiC:Al, SiC:B, Si:B and C:B in terms of the different ionization energies of their acceptors.

We are installing at CEA-Saclay a demonstration setup for an intense positron source. It is based on a compact 5.5 MeV electron linac used to produce positrons via pair production on a tungsten target. A relatively high current of 0.15 mA compensates for low positron efficiencies at low energy, which is below the neutron activation threshold. The expected production rate is 5⋅1011 fast positrons per second. A set of coils is arranged to select the fast positrons from the diffracted electron beam in order to study the possibility of using a rare gas cryogenic moderator away from the main flux of particles. The commissioning of the linac is under way. This setup is part of a project to demonstrate the feasibility of an experiment to produce the H+ ions for a free fall measurement of neutral antihydrogen (H). Its small size and cost could be of interest for material science applications, after adaptation of the time structure.

International audience; Multiply charged ion beam transmission through insulating capillaries is today a very active field of research. Thanks to the work of several groups during the last five years, several features of this unexpected process have been evidenced. The open challenge is to understand and control the self-organized charging-up of the capillary walls, which leads finally to the ion transmission. Up to now, the specific charge distribution on the inner surface, as well as the dynamics of the build-up, are still to be understood. While capillaries usually studied are microscopic pore networks etched in different materials, our concern is in macroscopic single capillaries made of glass. With a length of several centimeters and a diameter of a few micrometers at the exit, these capillaries have nevertheless the same aspect ratio as the etched pores (length/diameter ≈ 100). One of the leading goals of this research on single capillaries is to produce multi-charged ion beams with diameters smaller than a micrometer (nano-beams). These glass capillaries offer the opportunity to be used as an ion funnel due to their amazing properties of guiding and focusing highly charged ion beams without altering neither their initial charge state nor the beam emittance (

Salivary SPECT and factor analysis in Sjögren's syndrome were performed in 17 patients and 6 volunteers as controls. The ability of SPECT to detect small differences in the level of uptake can be used to separate glands from background even when uptake is reduced as in the patients with Sjögren's syndrome. In control and probable Sjögren's syndrome groups the uptake ratio of the submandibular gland to parotid gland on salivary SPECT (S/P ratio) was less than 1.0. However, in the definite Sjögren's syndrome group, the ratio was more than 1.0. Moreover, the ratio in all patients with sialectasia, which is characteristic of Sjögren's syndrome, was more than 1.0. Salivary factor analysis of normal parotid glands showed slowly increasing patterns of uptake and normal submandibular glands had rapidly increasing patterns of uptake. However, in the definite Sjögren's syndrome group, the factor analysis patterns were altered, with slowly increasing patterns dominating both in the parotid and submandibular glands. These results suggest that the S/P ratio in salivary SPECT and salivary factor analysis provide additional radiologic criteria in diagnosing Sjögren's syndrome.

Inelastic x-ray scattering and $ab$-$initio$ calculation are applied to investigate the lattice dynamics and electron-phonon coupling of the ternary silicide superconductor CaAlSi ($P/bar{6}m2$). A soft c-axis polarized mode is clearly observed along the $/Gamma$-$A$-$L$ symmetry directions. The soft mode is strongly anharmonically broadened at room temperature, but, at 10 K, its linewidth narrows and becomes in good agreement with calculations of linear electron-phonon coupling. This establishes a coherent description of the detailed phonon properties in this system and links them clearly and consistently with the superconductivity., Comment: 4 pages, 4 figures, to be published in Phys. Rev. B (Rapid Communications)

A model system is studied via Molecular Dynamics (MD) simulation. The system consists of 3,200 molecules placed in the rigid cubic cell with the periodic boundary condition. A molecule has 100 united atoms which are assumed the CH2. The molecule has the bonds between the united atoms nearby, the bends to the next bond, and the torsional potential. The motions of the united atoms in the model system have at least three time stages before the time region of the system relaxation. The first stage is marked by the ballistic motion. The second stage is marked by the motion in some cage. The third stage is marked by the collective motion with the surrounding united atoms. The fourth stage is marked by the elementary process which causes the system relaxation for long time.

The discoveries of superconductivity in the heavily-boron doped semiconductors diamond (C:B) in 2004 and silicon (Si:B) in 2006 have renewed the interest in the physics of the superconducting state of doped semiconductors. Recently, we discovered superconductivity in the closely related ''mixed'' system heavily boron-doped silcon carbide (SiC:B). Interestingly, the latter compound is a type-I superconductor whereas the two aforementioned materials are type-II. In this paper we present an extensive analysis of our recent specific-heat study, as well as the band structure and expected Fermi surfaces. We observe an apparent quadratic temperature dependence of the electronic specific heat in the superconducting state. Possible reasons are a nodal gap structure or a residual density of states due to non-superconducting parts of the sample. The basic superconducting parameters are estimated in a Ginzburg-Landau framework. We compare and discuss our results with those reported for C:B and Si:B. Finally, we comment on possible origins of the difference in the superconductivity of SiC:B compared to the two ''parent'' materials C:B and Si:B., Comment: 9 pages, 7 figures, 2 tables, submitted to Phys. Rev. B

Due to the strong evolution in the field of nanotechnologies and the continuous miniaturisation of electronic components, multiply-charged ion nanobeams would be a promising tool in this field of research. Either for surface modification or local (nanometer scale) surface analysis purposes, studying the feasibility of such beams is of strong interest. In the present contribution, we present a focusing technique based on the self-organised charge-up of a simple glass ‘funnel'.

CT scans of 279 normal subjects and 78 patients with a pancreatic head mass were reviewed. The mean width of the pancreatic body in normal subjects was 15.8 ± 2.9 mm, but the width decreased with age. The pancreatic head to body width ratio (H/B ratio) was constant (1.45 ±0.03). In 56 patients with carcinoma, the pancreatic body width decreased as tumor size increased and uniform atrophy with continuous beading duct was common in large carcinomas. The H/B ratio in small carcinomas (< 2 cm), however, was significantly smaller than normal (p < 0.05) and an enlarged pancreatic body was seen in 55 percent of these cases. The pancreatic body width in focal inflammatory masses was large compared to that in carcinomas of comparable size; the H/B ratio (1.57) was close to normal and the duct caliber to gland width ratio was low (0.16), even with large lesions. Non-uniform pancreatic body with discontinuous duct was most commonly associated with pseudocyst. Characterization of the CT appearance of secondary changes in the pancreatic body may help to improve the diagnosis of pancreatic head mass.

We have measured deexcitation x rays emitted from the resonant coherently excited 2{sup 1}P{sub 1} state of heliumlike Fe{sup 24+} ions of 423 MeV/amu, planar channeling through a Si crystal. Large anisotropy in the angular distribution of deexcitation x-ray emission is observed: the x-ray emission in the direction parallel to the channeling plane is favored by a factor of 2 compared to the perpendicular direction. This anisotropy originates from the direction of the periodic crystal field, which populates specific m states in resonant coherent excitation and aligns the excited states.

We have measured deexcitation x rays emitted from the resonant coherently excited 2(1)P(1) state of heliumlike Fe24+ ions of 423 MeV/amu, planar channeling through a Si crystal. Large anisotropy in the angular distribution of deexcitation x-ray emission is observed: the x-ray emission in the direction parallel to the channeling plane is favored by a factor of 2 compared to the perpendicular direction. This anisotropy originates from the direction of the periodic crystal field, which populates specific m states in resonant coherent excitation and aligns the excited states.

Expérience GANIL (SME); International audience; We present here a review of the experimental results obtained these last years at CIRIL laboratory in the field of swift heavy ion-induced small molecule fragmentation dynamics. Using the high ionizing power of highly charged ions, we study the formation and decay dynamics of charged molecules. We evidence the role of the excited states of the transient molecular ion populated before dissociation. The evolution of the experimental setup from coincident time of flight spectroscopy to reaction microscope, in conjunction with calculations taking into account these excited states, opens the way to multi-differential cross-sections measurements. A deep insight is now possible, for example, in the study of polyatomic molecule bond breakage selectivity. A special attention is actually paid to the electron emission description in the molecular frame in order to evidence some specific effects inherent to the molecular nature of the target.

The authors have proposed FRIENDS as a concept of the future electric power delivery system. In FRIENDS, new facilities called Quality Control Centers (QCCs) are installed between distribution substation and customers and they constitute new high voltage distribution network in which QCC becomes node. One of the most important function of FRIENDS is to improve the reliability of power supply by utilizing the distributed generators as backup generators. In order to use DGs as backup generators, the fast and effective operation manner has to be developed. Under the above backgrounds, the authors have proposed the distributed autonomous emergency operation of FRIENDS network under the assumption that all QCCs are completely generous to cooperative emergency operation. This paper proposes the advanced operation algorithm which can correspond to the partially uncooperative situation and investigates the validity of the advanced algorithm through the Monte Carlo simulation.

Beyond the scaling limit of Si CMOS LSls, one envisages nanoelectronics based on quantum devices. To realize quantum LSls (Q-LSIs), however, a novel architecture is required that is suitable to non-robust and charge-sensitive quantum devices which manipulate a single or a few electrons. The cascaded logic gate architecture in Si LSIs is utterly unsuitable. The purpose of this paper is to propose a graph-based Q-LSI architecture and to investigate its basic feasibility by forming of high-density GaAs-based and InP-based multi-branch nanowire networks and controlling them by nanometer-scale Schottky gates.

This paper proposes the variable bit rate TDM (VTDM) switch architecture, which not only has the advantage of TDM but also can support VBR traffic. The VTDM frame is designed for accommodating video data by enlarging the size of the time slot and synchronizing the VTDM frame length with the video frame interval. The double-buffer scheme allows a guarantee of maximum switching delay and a slight delay jitter. It is shown that adequate performance can be achieved by simply applying traffic shaping. By utilizing the header information of the VTDM frame and the scheduler operation, an intelligent priority control, leading to picture quality attainment, can be implemented.

The VTDM switching architecture has been proposed as a new worthwhile solution for VBR video transmission. The VTDM requires real-time and efficient time slot assignment, which is performed in every frame period. We propose two algorithms that are efficient, fast and practical for hardware implementation.

We present recent results on the hydrodynamic instability experiments on the HIPER (High Intensity Plasma Experimental Research) laser facility at Institute of Laser Engineering, Osaka University. We measured the Rayleigh‐Taylor growth rate on the HIPER laser. Also measured were all parameters that determine the RT growth rate. We focused on the measurements of the ablation density of laser‐irradiated targets, which had not been experimentally measured. The experimental results were compared with calculations with one dimensional simulation coupled with and without Fokker‐Planck equation for electron heat transport.

Two cases of pancreatic lymphoepithelial cyst are presented. Abdominal ultrasonography and endoscopic ultrasonography demonstrated cysts containing keratinized material, indicative of this diagnosis.

We studied the effect of acetophenone coating on the surface potential of the low-density polyethylene (LDPE) films which had been inserted between plane electrodes after the removal of the upper brass disk electrode. The results for the films with coating were compared with those without coating. The polarity of the surface potential for the uncoated films was always the same as that of the applied step voltage which had been subjected to the upper electrode and then shorted, and the absolute value of the surface potential tended to increase to a constant value of about 600 V with increasing the applied voltage and also with the short circuit time for both polarities of applied voltage. The surface potential for the coated films was usually lower than that for the uncoated film and the value tended to be scattered from sample to sample. Sometimes, opposite polarity to the applied voltage was observed, even though the height was low. The increase in the short circuit time decreased the surface potential, unlike the case without acetophenone coating. These results were discussed on the basis of the charge distribution in the bulk of LDPE film.