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1.
A. Nakano T. Shimazaki M. Sekiya H. Shiozawa K. Ohtsuka A. Aoyagi T. Iwakiri Z. Mikami M. Sato Y. Sugino K. Kinoshita T. Matsuoka T. Imamura Y. Takayama K. Yamamoto 《International Journal of Hydrogen Energy》2021,46(29):15649-15659
Monitoring the temperature in liquid hydrogen (LH2) storage tanks on ships is important for the safety of maritime navigation. In addition, accurate temperature measurement is also required for commercial transactions. Temperature and pressure define the density of liquid hydrogen, which is directly linked to trading interests. In this study, we developed and tested a liquid hydrogen temperature monitoring system that uses platinum resistance sensors with a nominal electrical resistance of approximately 1000 Ω at room temperature, PT-1000, for marine applications. The temperature measurements were carried out using a newly developed temperature monitoring system under different pressure conditions. The measured values are compared with a calibrated reference PT-1000 resistance thermometer. We confirm a measurement accuracy of ±50 mK in a pressure range of 0.1 MPa–0.5 MPa. 相似文献
2.
A method was developed for administering intrathecal pharmacotherapy in a rat model of spinal cord injury. The effects of intrathecal administration of nimodipine on spinal cord blood flow (SCBF) and evoked potentials (EPs) were measured in the normal and injured spinal cord. It had previously been shown that systemic nimodipine caused severe hypotension after spinal cord injury. After baseline SCBF and EPs, 15 uninjured rats were blindly allocated to one of three groups: one placebo group (n = 5); and two groups with intrathecal nimodipine, 0.05 mg/kg (n = 5), or 0.2 mg/kg (n = 5). Ten other rats received a 35 g acute clip compression injury of the spinal cord for 1 minute and, were allocated to one of two groups: placebo (n = 5); and intrathecal nimodipine 0.05 mg/kg (n = 5) given 60 min after injury. In the uninjured groups, neither 0.05 nor 0.2 mg/kg of nimodipine increased SCBF during, or 30 min after, intrathecal infusion. However, the mean arterial blood pressure (MABP) decreased significantly to 69.73.1% after the infusion of 0.2 mg/kg nimodipine and did not recover by 98 min. In all three groups of uninjured rats, the amplitude of the cerebellar EP was decreased 30 min after infusion. After spinal cord injury, there were significant decreases in MABP, SCBF and EP amplitude in both placebo and treatment groups, but there was no therapeutic benefit from nimodipine. Thus, intrathecal infusion of nimodipine did not prevent the hypotension encountered with systemic administration and exerted no beneficial effect on SCBF or EPs after acute spinal cord injury. 相似文献
3.
Cold-rolling texture and partially recrystallized texture of polycrystalline 3 pct Si-Fe were investigated using high-resolution
electron backscattered diffraction (EBSD) method. From the measurement on a deformed grain with {211}〈011〉∼{111}〈011〉 orientations,
deformation bands with {12 4 1}〈014〉 orientation were found. It turned out that the orientation rotation relationship between
deformation bands and surrounding deformed grain can be explained by the activation of the slip system, which has a common
slip plane with an adjacent grain. Oriented nucleation of recrystallized grains with {12 4 1}〈014〉 orientation was observed
in a deformed grain with {211}〈011〉∼{111}〈011〉 orientation. Exactly the same orientation relationship that was observed between
deformed grain and the deformation bands was also observed between the deformed grain and the recrystallized grain. A hypothesis
that recrystallization nuclei are generated directly from the deformation bands formed by an activation of the slip system
that has a common slip plane of neighboring deformed grains was proposed from the present experimental results. 相似文献
4.
Directional couplers are successfully fabricated on acrylic substrates using polymers synthesised from deuterated methacrylate and deuterated fluoromethacrylate monomers. The excess loss of a 50 mm long coupler is about 0.7 dB including waveguide and fibre coupling losses. A novel method is proposed for tuning the coupling ratio. By bending the coupler, high precision control of within 1% is attained without optical polarisation dependence.<> 相似文献
5.
Creep crack growth rates were measured using centrally cracked tension specimens of thin polypropylene film with different
crack lengths at various stresses and temperatures. The creep crack growth rates were correlated with the stress intensity
factor. There was the region of the minimum constant crack growth rate which occupied more than 70% of the total creep failure
life. This constant creep crack growth rate characteristics were analyzed on the basis of the stress-dependent Arrhenius type
thermally activated process. 相似文献
6.
The favorable therapeutic effect of preoperative portal vein embolization (PVE) was analyzed by assessing various volumetric, cell kinetic and morphometric parameters and examining histologically the embolized and nonembolized lobes of 15 patients who underwent extended right lobectomy 2 to 3 weeks after PVE. Each lobar volume was calculated from computed tomography (CT) images, hepatocyte proliferation was evaluated by assessing proliferative cell nuclear antigen (PCNA) expression and mitosis, hepatocyte apoptosis was evaluated by the terminal deoxyribonucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay, and the hepatocyte numerical density as well as the sinusoidal volumetric ratio (Vvs) and the mean hepatocyte volume (Cv) were calculated using morphometric methods. PVE induced hepatocyte apoptosis and atrophy of the embolized lobe (from 798 +/- 213 to 708 +/- 222 cm3; P < .05). The increased sinusoidal volume in this lobe (17.7% +/- 4.5% and 21.7% +/- 5.7%, periportal and pericentral area, respectively) may have been attributable to hepatocyte deletion. Cells in the nonembolized lobe entered a highly active phase of proliferation within 2 weeks after PVE. Further evidence of cellular proliferation was provided by the increased nonembolized lobar volume (from 379 +/- 132 to 545 +/- 130 cm3; P < .01) and numerical density of hepatocyte nuclei (Nv) (5.38 +/- 1.26 vs. 3.11 +/- 0.85 x 10(5)/mm3; P < .01, nonembolized vs. embolized lobe, respectively). In conclusion, these results indicate that the favorable effect of PVE is attributable to a net gain of functional hepatocyte mass and/or early induction of hepatocyte proliferation following hepatectomy. 相似文献
7.
Care of esophageal cancer patients with diabetes mellitus--preoperative management and treatment 总被引:1,自引:0,他引:1
The care of esophageal cancer patients with diabetes mellitus is described. The main points are as follows. 1. Prevention and control of infection. 2. Sufficient nutritional support (2000 Kcal/day) and hydration. 3. Control of plasma glucose level (150 mg/dl-250 mg/dl) by means of insulin. 4. An absence of ketone bodies and minimum glucose level (< 10 g/day) in the urine. 5. Prevention and control of hypoglycemia. Good control of diabetes mellitus in esophageal cancer patients may contribute to reduced surgical rislcs. 相似文献
8.
Applied Intelligence - A multi-agent system (MAS) is expected to be applied to various real-world problems where a single agent cannot accomplish given tasks. Due to the inherent complexity in the... 相似文献
9.
S. Takadono H. Iwahori T. Yabushita Y. Imamura H. Ishizuka S. Tamaru 《Desalination》1984,49(3):347-355
Membrane fouling by suspended solids is a severe problem in reverse osmosis or ultrafiltration of highly fouling feed streams. Tubular membrane systems are inherently fouling resistant and can be automatically mechanically cleaned at regular intervals by a sponge ball cleaning device. The use of this type of system to process a number of highly fouling feed streams difficult to treat by membrane processes is described 相似文献
10.
The melting points (Tm) were measured for oligomers obtained by a direct continuous esterification process between terephthalic acid and ethylene glycol. Multiple regression analyses of data were carried out, and an equation was obtained for predicting melting points with correlation coefficient of ~0.99. 相似文献