13C NMR spectrum analysis of electrochemically prepared poly(3-methylthienylene) films

The ¹³C NMR spectrum analysis of electrochemically prepared poly(3-methylthienylene) films has been investigated. Both a film doped with ClO₄ ions (P3MT-ClO₄) and an undoped film (P3MT₀) give only two distinct absorption bands through the electrochemical reduction of P3MT-ClO₄. These distinct bands are definitely attributable to the methyl group (upper field) and the thiophene ring (lower field), respectively, and are characteristic of well-defined poly(3-methylthienylene). The correlation between conductivity and ¹³C NMR spectra will be discussed.     

Combination phase I/II study of irinotecan hydrochloride (CPT-11) and carboplatin in relapsed or refractory non-Hodgkin's lymphoma. CPT-11/Lymphoma Study Group

Irinotecan hydrochloride (CPT-11) is a new derivative of camptothecin which inhibits topoisomerase I. Phase II studies have demonstrated that CPT-11 is active against a broad spectrum of neoplasms including intractable non-Hodgkin's lymphoma. An early phase II study in lymphoma suggested that a schedule of daily infusions of 40 mg/m2/day for three or five consecutive days is more effective than a single infusion of 200 mg/m2 every three to four weeks. Carboplatin is also an active agent against lymphoma, and preclinical studies have shown that CPT-11 and its active metabolite have a synergistic effect with platinum compounds. To evaluate the maximal tolerated dose (MTD) and the therapeutic efficacy of CPT-11 in combination with carboplatin in relapsed or refractory non-Hodgkin's lymphoma, we conducted a combination phase I/II study. The starting dose of CPT-11 was 20 mg/m2/day (days 1 through 3 and 8 through 10), and dose escalations of 5 mg/m2/day increments were planned, with a fixed dose of carboplatin (300 mg/m2, day 1). Six of the eight patients receiving both agents at the starting dose level developed critical toxicities such as grade 4 hematologic (neutropenia 6/8, thrombocytopenia 1/8) and grade 3 non-hematologic toxicities (diarrhea 2/8, transaminase elevation 1/8). Further dose escalation of CPT-11 was halted, and the starting doses were judged to be the MTDs. The response rate (25%, 2/8) to the combination of the MTDs was not superior to that of CPT-11 alone in a previous phase II study (38%, 26/69), and the MTD of CPT-11 in combination with carboplatin was less than half the single-agent dose. We conclude that carboplatin is not recommendable for combination with CPT-11 in lymphoma patients. Other suitable agents for such a combination should be sought.     

Influence of drying and water supplying after drying on tensile strength of cement mortar

This paper is concerned with the change in tensile strength of cement mortar sibjected to rapid drying and water supply after drying. Flexural strength was investigated for several cement paste specimens cured in water for a certain period, with some specimens dried for 1 day and cured again in water after drying. As a result, it is known that the flexural strength of the specimen allowed to dry becomes about of that of a sound specimen, but it is almost recovered after about 3 h water curing after drying. The reason why the strength changes is usually connected with a restrained stress due to drying shrinkage and a stress relaxation due to expansion caused by water absorption. However, when the restrained stress at the surface overtakes the tensile strength, and a considerable number of minute cracks occur, as was observed, the above explanation cannot be accepted, because the tensile stress is almost perfectly relaxed by the occurrence of the cracks. In this paper, the reason for the strength recovery as a result of water absorption is reconsidered by means of stress analysis and microscopic examination of the cracks.     

Effects of uni-axial mechanical stress on IGBT characteristics

This paper describes the impacts of mechanical stress on vertical power devices. The stress dependence of the DC characteristics of trench insulated gate bipolar transistors (IGBTs) was measured. The experimental results could be reproduced by the device simulation, which included stress dependence models of the carrier mobility and the band gap. We found that the stress dependence of the on-state voltage mainly arose from the MOSFET portion of the IGBT. Using the device simulation, we estimated the effects of mechanical stress on the surge voltage and the saturation current, which give us the important information for designing a power module with higher ruggedness.     

PLL-based BiCMOS on-chip clock generator for very high-speedmicroprocessor

Described is a phase-locked loop (PLL)-based BiCMOS on-chip clock generator (PCG), which is used to generate an internal clock synchronized to a reference clock from outside the chip. In order to obtain a very wide operation bandwidth, it is proposed that the PCG include a compensation circuit for voltage-controlled oscillator (VCO) operation. The compensation circuit varies the oscillation bandwidth of the VCO according to the reference clock frequency, preventing the expected oscillation frequency from being outside the oscillation bandwidth. The PCG is designed and fabricated with 1.0 μm BiCMOS technology, and it achieves an operation bandwidth of 3 to 90 MHz     

An 8-b ADC with over-Nyquist input at 300-Ms/s conversion rate

An 8-b flash analog-digital (A/D) converter (ADC) LSI for high-speed data acquisition systems such as digital oscilloscopes and wave digitizers is described. This converter can convert analog input signals over the Nyquist frequency (up to 200 MHz) at a conversion rate of 300 megasamples per second (Ms/s) without glitch errors. In addition, it can be operated at up to 440 Ms/s when input frequency is as low as 100 kHz. This ADC is fabricated by a 2.5-μm, 10-GHz f_T , Si bipolar technology called the advanced sidewall base contact structure (advanced SICOS) technology. For high-performance glitch error suppression, an inhibitory circuit and a comparator design with an inner clock buffer are developed. Both techniques require few hardware additions     

3.3-V BiCMOS circuit techniques for a 120-MHz RISC microprocessor

This paper describes 3.3-V BiCMOS circuit techniques for a 120-MHz RISC microprocessor. The processor is implemented in a 0.5-μm BiCMOS technology with 4-metal-layer structure. The chip includes a 240 MFLOPS fully pipelined 64-b floating point datapath, a 240-MIPS integer datapath, and 24 KB cache, and contains 2.8 million transistors. The processor executes up to four operations at 120 MHz and dissipates 17 W. Novel BiCMOS circuits, such as a 0.6-ns single-ended common base sense amplifier, a 0.46-ns 22-b comparator, and a 0.7-ns path logic adder are applied to the processor. The processor with the proposed BiCMOS circuits has a 11%-47% shorter delay time advantage over a CMOS microprocessor     

13C NMR and Fourier transform infrared study of electrochemically prepared polythienylene film

The ¹³C NMR and Fourier transform infrared (FTIR) spectra of an electrochemically prepared polythienylene film have been obtained. The polythienylene film displays only two sharp absorption bands, at 124.8 and 136.5 ppm downfield from TMS (tetramethylsilane) in the ¹³C NMR, these being attributable to the carbon atoms in the β-position and the α-position, respectively, relative to the sulfur atom of poly(2,5-thienylene). The polythienylene film also shows a sharp absorption band at 789 cm^?1 in the IR, which is definitely ascribable to the C-H out-of-plane vibration of poly(2,5-thienylene). The polythienylene film will be shown to have a highly defined structure with a dominance of poly(2,5-thienylene).