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排序方式: 共有1267条查询结果,搜索用时 15 毫秒
1.
The copreheat-treatment of non-fusible and slightly fusible coals with A240 and hydrogenated A240 under high temperature-short contact-time conditions around 500 °C has been examined in an attempt to produce a formed coke with better anisotropic development. These conditions shortened the copreheat-treatment time and provided better anisotropic development in the resultant coke after carbonization. Effectiveness of short contact-time has been discussed in terms of the extent of depolymerization of coal molecules suitable for anisotropic development, this being related to coal liquefaction under similar conditions. 相似文献
2.
H Kato T Takashima H Kishikawa S Emura K Ohmori 《Canadian Metallurgical Quarterly》1997,51(8):489-490
We studied urinary N-acetyl-beta-D-glucosaminidase (NAG) in the early stage of diabetic nephropathy in 27 non-insulin-dependent diabetes mellitus (NIDDM) patients with a microalbumin level below 20 mg on 24-hour urine sample. Microalbumin and NAG excretion were measured in 24-hour urine samples collected on three separate occasions within seven days of admission. Creatinine clearance was determined simultaneously. There was a significant negative correlation between the creatinine clearance and 24-hour urinary NAG (r = -0.38, p < 0.05). Elevation of urinary NAG may indicate decreased renal function during early stage NIDDM nephropathy. 相似文献
3.
Bonding of ceramics to metals was carried out by using thermal sprayed coatings as interlayer materials. This bonding method is referred as the thermal spray bonding. In the present study, Si3N4 and Al2O3 ceramics were bonded to SS41 mild steel using activated Ti-Cu multilayer coatings plasma-sprayed on the steel in a low pressure atmosphere. The bondability was estimated by SEM/EDX analysis and shear tests of the joints. The results were compared to those obtained using Ti-Cu multilayer foils as interlayers. When using Ti-Cu foils as interlayers, brittle Fe-Ti compound layers were formed in the joint area after long time heating at a bonding temperature of 900°C, which deteriorated the joint strength. In contrast with the activated interlayers made by plasma spraying, the Ti-Cu eutectic reaction took place uniformly at the joint immediately after heating to the bonding temperature. This improved the bondabilrty, and the resultant joints exhibited shear strengths of about 180 MPa. 相似文献
4.
Toshiaki Nishihata Mayumi Ishizaka Sigeharu Yokohama Alice C. Martino Roger E. Gordon 《Drug development and industrial pharmacy》1993,19(20):2679-2698
The effects of particle size and food on the absolute bioavailability of U-78875 in dogs after oral administration of either a suspension or tablet dosage form were investigated. A reduction of particle size caused a significant increase in bioavailability along with an increase in dissolution rate. Additionally, both suspension and tablet dosage forms administered after food caused an increase in bioavailability. Thus, to accelerate drug dissolution, a reduction of U-78875 particle size from the unmilled state is important for the optimization of formulation compositions. To increase the bioavailability of U-78875, postprandial dosing should be considered. 相似文献
5.
T Nakajima K Miwa Y Ohmori T Sakabe M Fujii T Kajitani 《Canadian Metallurgical Quarterly》1996,23(9):1161-1168
A multi-center collaborative study was conducted in curatively resected gastric cancer patients at Stages II and III to compare oral 5-FU (Group A), oral Tegafur (Group B) and i.v. MMC + oral 5-FU (Group C). From May 1982 to April 1985, 1,012 cases were enrolled at 55 institutions. Some 138 (13.8%) were excluded, and 874 were analyzable. In the analysis of background factors, Group B had more cases with tumor of large diameter and advanced Stage. Adverse effects were relatively mild in all groups, and there was no problem in drug tolerance. Five-year survival rate was 67.6%, 62.4% and 68.6% in Groups A, B and C, respectively, reflecting no significant difference among them. It was 85.0%, 83.0% and 81.1% in Stage II and 52.5%, 51.0% and 59.0% in Stage III of Groups A, B and C, respectively. No significant difference was found, but Stage III of Group C showed a slightly higher survival rate. Supportive clinical study will be required to assess the usefulness of MMC as an introduction therapy. We found no difference in efficacy between 5-FU and Tegafur as maintenance therapy. The life-prolongation effect of fluoropyrimidines in comparison with surgery alone should be studied separately. 相似文献
6.
In this study, current collecting efficiency of the micro tubular solid oxide fuel cell (SOFC) was estimated to determine optimum size of the micro tubular SOFC. Two models for collecting current from single terminal (ST) and double terminal (DT) of anode tube were proposed and used to calculate the current collecting efficiency as functions of anode thickness, tube length and operating temperature. It was shown that design of the cell geometry and current correcting method are significantly important to achieve high performance micro tubular SOFC stacks. The efficiency loss estimated from the DT model was about 2–4-fold lower than those of obtained from the ST model. The DT model was shown to be more effective for higher operating temperature and the tube length. 相似文献
7.
Eight-channel flat spectral response arrayed-waveguide multiplexer with asymmetrical Mach-Zehnder filters 总被引:1,自引:0,他引:1
K. Okamoto K. Takiguchi Y. Ohmori 《Photonics Technology Letters, IEEE》1996,8(3):373-374
An eight-channel flat spectral response arrayed-waveguide grating (AWG) multiplexer with asymmetrical Mach-Zehnder filters has been fabricated on the planar lightwave circuit (PLC). The monotonic spectral loss characteristics of AWG have been canceled by the opposite spectral response in the asymmetric MZ filter. The 1.5 dB bandwidth of 141 GHz and 3 dB bandwidth of 159 GHz are obtained for the 200 GHz channel spacing. The 1.5 dB bandwidth becomes 1.8 times wider than that of the conventional AWG. Crosstalks to neighboring and all other channels are less than -24 dB and the on-chip insertion losses range from 7.0 to 7.4 dB, respectively. 相似文献
8.
Tomohito Kameda Kazuya Horikoshi Shogo Kumagai Yuko Saito Toshiaki Yoshioka 《中国化学工程学报》2021,28(12):2993-3001
In this paper, we propose that the urinary toxins from the wastewater be adsorbed on an adsorbent such as spherical activated carbon and the latter be regenerated by subjecting it to high temperatures to recycle activated carbon and also to recycle the water used in dialysis. We studied the adsorption of artificial waste dialysate, which is a mixed solution of urea, creatinine, and uric acid, and the separate solutions for each of these and found that their extents of adsorption onto the spherical activated carbon material were nearly identical. The amount of adsorption was approximately 1.4 mg·g-1 for urea, 18 mg·g-1 for creatinine, and 20 mg·g-1 for uric acid. The urea, creatinine, and uric acid adsorbed onto the spherical activated carbon decomposed on heat treatment at 500℃, and the adsorption capacity of the spherical activated carbon was regenerated. Our study successfully demonstrated that the spherical activated carbon can be recycled in the waste dialysate treatment process. 相似文献
9.
A WC-Co coating was sprayed by the high-velocity oxyfuel process using a feedstock of tungsten carbide clad with cobalt. The
structure of the sprayed coating was characterized by x-ray diffraction (XRD), differential scanning calorimetry (DSC), and
differential thermal analysis (DTA). It was found that an amorphous phase of Co-W-C ternary alloy observed as a large, broad
peak in the XRD pattern can be formed in the as-sprayed WC-Co coating. The DSC, DTA, and XRD analyses revealed that the amorphous
phase crystallized at a temperature of around 873 K to metallic cobalt, Co6W6C, and tungsten with appreciable precipitation of free carbon. The heat treatment of as-sprayed WC-Co coating at a high temperature
of 1173 K suggests that annealing at a temperature higher than about 1104 K will promote the reaction of tungsten and cobalt
with carbon to form the complex carbide C06W6C. 相似文献
10.
A high-performance liquid chromatographic method, using post-column detection with diphenyl-1-pyrenyl-phosphine (DPPP), was
developed for the quantitative and qualitative determination of isomeric lipid hydroperoxides (OOH). The OOH eluted from a
normal-phase column were passed through a photodiode array detector and then mixed with DPPP solution in a reaction coil heated
at 80°C. DPPP oxide formed by the reaction with OOH was determined by monitoring the fluorescence intensity at 380 nm and
excitation at 352 nm. The conjugated diene OOH (13-cis, trans- and 9-cis, trans-OOH) and nonconjugated OOH (12-cis-trans- and 10-cis, trans-OOH) from photosensitized oxidation of methyl linoleate were determined in a molar ratio of 31∶29∶19∶21, respectively. However,
only the two conjugated hydroperoxides were detected by ultraviolet absorption at 234 nm. Further applications were carried
out for the determination of OOH of methyl oleate and methyl linolenate. This method proved to be useful for the determination
of the OOH containing both conjugated and nonconjugated diene structures. 相似文献