Microwave dielectric properties of mixed phase ceramics, Ba(Zn1/3Ta2/3)O3–xCaTiO3 and xMgTiO3–yCaTiO3–z(Nd2O3,wTiO2)

The effect of different chemical compositions on the microwave dielectric properties of Ba(Zn_1/3Ta_2/3)O₃–xCaTiO₃ and xMgTiO₃–yCaTiO₃–z(Nd₂O₃,wTiO₂) was studied. High fQ dielectrics were designed by optimizing composition and firing conditions. Adding up to 1 mol % CaTiO₃ to Ba(Zn_1/3Ta_2/3)O₃ increased ε_r from 25 to 30 at a firing temperature of 1450 °C, and produced very high fQ values of more than 100 000 GHz at a firing temperature of 1550 °C. EPMA and XRD suggested that ceramics based on Ba(Zn_1/3Ta_2/3)O₃ with CaTiO₃ had mixed phases of Ba(Zn_1/3Ta_2/3)O₃ and Ca–Ti–Zn–O. Addition of CaTiO₃ increased the Ba(Zn_1/3Ta_2/3)O₃ peak observed in XRD and decreased the Ba₃Ta₂O₈ peak. Prolonged sintering of Ba(Zn_1/3Ta_2/3)O₃ with CaTiO₃ increased the fQ value but kept ε_r constant. 0.5MgTiO₃–0.5CaTiO₃–z(Nd₂O₃,wTiO₂) showed a high dielectric constant ε_r>40 and fQ>20 000 GHz. When w=1, τ_f decreased linearly with z around 0 ppm/ °C in 0.5MgTiO₃–0.5CaTiO₃–z(Nd₂O₃,TiO₂) (0.25≤z≤0.5). X-ray and EDX analysis revealed a mixed phase matrix of MgTiO₃ and (Ca_1?αNd_2α/3)Ti_βO₃. It was concluded that ε_r of the high fQ materials Ba(Zn_1/3Ta_2/3)O₃–xCaTiO₃ and xMgTiO₃–yCaTiO₃–z(Nd₂O₃,wTiO₂) would be increased by varying their chemical compositions, x, y, z, and w, and that their fQ value would be improved by appropriate choices of heating temperature and time.     

A 30-MHz mixed analog/digital signal processor

A multiplying encoder architecture that is implemented in the design of a mixed analog and digital signal processor is presented. The processor is suitable for performing both high-speed A/D conversion and digital filtering in a single chip. The device can resolve the input with 8 b at 30 Msample/s and perform 28 multiply and 28 add operations per sample under typical conditions. The processor is designed for a 28-tap programmable FIR (finite impulse response) filter with analog input signal which can be used for waveform shaping of the modem to obtain the desired transmission performance for business satellite communication and mobile communication. The chip is fabricated in a 1-μm double-polysilicon and double-metal CMOS technology. The chip size is 9.73×8.14 mm², and the chip operates with a single +5.0-V power supply. Typical power dissipation is 950 mW; 330 mW is dissipated in analog and 620 mW is in the digital block     

Clinical analysis in patients undergoing extended resection of pT3 non-small cell lung cancer

Among pT3 cases there contain various subgroups in terms of the organ which is involved in. We analyzed medical records of 85 consecutive patients who underwent extended surgery with diagnosis of pT3 excluding interlober invasion. As regards to the site of invasion, there are not significant differences in survival between pleural invasion, chest wall involvement, pericardial invasion, and diaphragmatic invasion. However, survival of patients who showed involvement of main bronchus seemed better than other groups. Survival of pT3 cases are in part determined by lymph node involvement, N0 group showed 36.0% 5 year survival rate whereas N1 group 20.0%, and there are no patient with N2 disease who survived 5 years. Among pleural and chest wall involvement group, N0 group showed 34.2% 5 year survival and there are no survival in N1 and N2 group. As regards to histologic subgroups, there are not significant differences between each group. Thus we conclude that in pT3 cases, N0 cases are the best candidate for surgical resection, and that adjuvant therapy is necessary for those with N1 or N2 involvement. Cases with bronchial extension should not be argued in the same field of locally invasive lung cancer because of better survival.     

Spectroscopic study of polytoluidines in the UV-visible and IR regions

Electropolymerization of o-toluidine(o-methylaniline) and m-toluidine was carried out in acidic aqueous solution, and UV-visible and IR spectra of the resulting polymer films were obtained at various electric potentials and pHs. In Na₂SO₄ aqueous solution, poly(o-toluidine) gave considerably different UV-visible spectra from polyaniline, whereas, in HCl (pH ～ 0), the spectra of poly(o-toluidine) changed in the same way as polyaniline when the potential was varied. This spectral change depended also on counterion. This suggests that the intermediate state (radical cation) of poly(o-toluidine) is unstable in a neutral solution especially when a large counter ion exists, which is contrast to polyaniline. The dependency of the FT-IR spectra of poly(o-toluidine) on the potential and pH supported also the above result of UV-visible spectra. From both UV-visible and IR spectra under various conditions, it was found that o-toluidine and m-toluidine give the same polymer.     

SUPERHEATED STEAM DRYING OF SINTERED SPHERES OF GLASS BEADS UNDER VACUUM

Drying of sintered spheres of coarse glass beads with a wide sintering range in superheated steam under vacuum was studied.

In samples with sintered angles of 7.5° -27°, the experimental normalized drying rates in superheated steam at pressures of 7.3-7.9mmHg were smaller than those for 56.0-767.6 mmHg in the vicinity of the critical moisture cotents for 56.0-767.6GmmHg. As reported in an earlier paper, there were     

Infected emphysematous bullae in a patient with diabetes mellitus

A 42-year-old woman with diabetes mellitus was admitted to our hospital because of fever, coughing, and dyspnea. Coarse crackles were audible and respiratory sounds were weak in the right lung field. Laboratory examination revealed a high erythrocyte sedimentation rate, a high level of serum C-reactive protein, a high blood sugar level, and hypoxemia. A chest roentgenogram revealed cystic lesions with fluid levels, and an infiltration shadow in the right lung field. A chest computed tomographic scan revealed many cystic lesions with fluid levels and an infiltration shadow. Our diagnosis was infected emphysematous bullae. A tube was inserted percutaneously for drainage and to allow injection of antibiotics into the cystic lesion. The cystic lesion then vanished. Percutaneous drainage and washing with antibiotics can be used to treat infected emphysematous bulla that have thick closed cystic walls.     

Rescue mission of Ryounkaku Tower in Great Kanto Earthquake; travelling back in time to 1923 to apply the latest aseismic technologies

In 1890, a twelve-story octagonal sight-seeing tower was constructed as a high rise building in Tokyo Asakusa Park. In 1923, however, the top of the tower from the eighth floor up collapsed due to the Great Kanto Earthquake. In order to raise public interest in disaster prevention, we performed as a virtual experiment a conceptual attempt to save the tower without fundamentally changing its architectural characteristics by applying the most advanced structural control techniques. In the simulation, the top of the tower from the eighth floor experienced, almost exactly as described in historical record, a shear fracture during the initial period of principal shock. The modified Ryounkaku Tower would have ensured a comfortable margin of safety even against earthquakes more severe than the Great Kanto Earthquake in 1923.     

Large‐screen displays using metal—insulator—metal cathode arrays

Abstract— Large‐screen (32‐in. WXGA and 17‐in. VGA) displays using metal—insulator—metal (MIM) cathode arrays have been developed. A cathode structure with low‐resistance electrodes and low‐capacitance emitters shortens signal delay and decreases the voltage drop in large MIM‐cathode arrays. By using a dual‐scan method, the signal delay was suppressed to less than 30% of the horizontal scan time in the 32‐in. WXGA panel. Emission efficiency of the cathode array was improved to 3% by reducing the surface work function of the top electrode from 4.7 to 3.9 eV. The cathode life was also improved to more than 10,000 hours. The display panel incorporating the cathode arrays and high‐efficiency P22‐phosphor screens with 3‐mm spacers showed high screen brightness (average brightness, 378 cd/m²; peak brightness, 832 cd/m²) at an anode voltage of 10 kV.