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181.
Fukuyama Y Yasuda N Kim J Murayama H Ohshima T Tanaka Y Kimura S Kamioka H Moritomo Y Toriumi K Tanaka H Kato K Ishikawa T Takata M 《The Review of scientific instruments》2008,79(4):045107
An ultra-high-precision clock system for long time delay has been developed for picosecond time-resolved x-ray diffraction measurements using synchrotron radiation (SR) pulses and synchronized femtosecond laser pulses. The time delay control between pump laser pulse and the probe SR pulse was achieved by combining an in-phase quadrature modulator and a synchronous counter. This method allowed us to change the delay time by a nearly infinite amount while maintaining the precision of +/-8.40 ps. Time-resolved diffraction measurements using the delay control system were demonstrated for precise measurement of an acoustic velocity in a single crystal of gallium arsenide. 相似文献
182.
Kazuo Matsuda Kenichi Kawazuishi Yoshiichi Hirochi Rei Sato Yasuki Kansha Chihiro Fushimi Yutaka Shikatani Hiroshi Kunikiyo Atsushi Tsutsumi 《Applied Thermal Engineering》2010,30(16):2300-2305
The reaction section of the naphtha hydro-desulfurization (HDS) process is a heating and cooling thermal process consisting of a feed/effluent heat exchanger and a fired heater. Energy savings are fundamentally made as a result of the maximized heat recovery in the heat exchanger and the reduced heat duty of the fired heater. To achieve further energy saving in the process, “self-heat recuperation technology” (SHRT) was adopted. In this technology, a compressor was introduced. The suction side of the compressor needed a lower pressure and the feed stream evaporated much easily. The discharged side of the compressor satisfied the operating conditions of both pressure and temperature at the inlet of the reactor. And the reactor effluent stream was able to be used completely to preheat and vaporize the feed stream. All the heat in the process stream was re-circulated without using a fired heater. SHRT was applied to the naphtha HDS process of 18,000 barrel per stream day (BPSD) in the refinery and the mass and energy balance of the process was calculated using commercially available simulation software, Invensys PROII version 8.1. This process-simulation case study confirmed that despite there being no more energy saving potential in the conventional process that makes use of a fired heater, the advanced process with SHRT can reduce the energy consumption significantly by using the recuperated heat of the feed stream. 相似文献
183.
Akiko Suzuki Mina Minamide Chihiro Iwaya Kenichi Ogata Junichi Iwata 《International journal of molecular sciences》2020,21(23)
Carbohydrates, fats, and proteins are the underlying energy sources for animals and are catabolized through specific biochemical cascades involving numerous enzymes. The catabolites and metabolites in these metabolic pathways are crucial for many cellular functions; therefore, an imbalance and/or dysregulation of these pathways causes cellular dysfunction, resulting in various metabolic diseases. Bone, a highly mineralized organ that serves as a skeleton of the body, undergoes continuous active turnover, which is required for the maintenance of healthy bony components through the deposition and resorption of bone matrix and minerals. This highly coordinated event is regulated throughout life by bone cells such as osteoblasts, osteoclasts, and osteocytes, and requires synchronized activities from different metabolic pathways. Here, we aim to provide a comprehensive review of the cellular metabolism involved in bone development and homeostasis, as revealed by mouse genetic studies. 相似文献
184.
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187.
Shinji Iijima Kenichi Kai Satoru Mizutani Takeshi Kobayashi 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1986,36(11):539-546
Escherichia coli harbouring a recombinant plasmid containing the α-amylase gene (HB101/pHI301) and its derivative which can stably maintain the plasmid (HB101/pHI301A) were cultivated in a mini-jar fermenter. By controlling dissolved oxygen (DO) at a concentration of 2–3 μg/l and supplementing with suitable amounts of nutrients, the organisms could grow to a concentration (up to 40 g dry cell l?1) in a semi-synthetic casamino acid medium. During culture the plasmid was maintained stably in both strains. In a synthetic medium, both micro-organisms grew less well and plasmid-free segregants were observed with HB101/pHI301 during the fed-batch culture. On the other hand, plasmid pHI301A was stably maintained throughout the fed-batch culture of HB101/pHI301A. Growth inhibitors, which may be metabolic products, accumulated in the medium and reduced bacterial growth. 相似文献
188.
H Tomioka R Fujiyama H Ohnishi T Sakurai K Tada H Sakamoto H Iwasaki K Imanaka K Hashimoto 《Canadian Metallurgical Quarterly》1997,35(12):1389-1394
UDP-glucuronosyltransferase (UGT) 2B9, isolated from a cynomolgus monkey liver cDNA library, is 89% identical to human UGT2B7 in primary amino acid sequence, and the two expressed enzymes were previously shown to catalyze the glucuronidation of many common endogenous substrates. The purpose of the present study was to characterize the reactivity of expressed UGT2B9 with important therapeutic agents and other xenobiotics. UGT2B9, stably expressed in human embryonic kidney 293 cells, catalyzes the 3-O- and 6-O-glucuronidation of morphine and the 6-O-glucuronidation of codeine. A number of other morphinan (e.g. naloxone, naltrexone, and nalorphine) and oripavine (e.g. buprenorphine) derivatives are substrates for this enzyme. In general, morphinan derivatives are glucuronidated at higher rates, compared with oripavines; however, glucuronidation efficiency values (Vmax/KM) for the compounds are similar. Stably expressed UGT2B9 also catalyzes the glucuronidation of profen nonsteroidal anti-inflammatory drugs, fibrate hypolipidemic agents, and straight-chain fatty acids at the carboxylic acid moiety. Monoterpenoid alcohols and propanolol are glucuronidated at aliphatic hydroxyl positions. Expressed UGT2B9 exhibits enantioselective glucuronidation for (R/S)-ibuprofen, (R/S)-propanolol, and (+)/(-)-menthol. The data suggest that monkey UGT2B9 and human UGT2B7 are functionally similar. 相似文献
189.
Immunological abnormalities (IA) are frequently observed in patients with myelodysplastic syndromes (MDS). Although there have been a number of analyses of the prognostic factors, there have been few studies, if any, to determine whether IA affects prognosis. We investigated the prognosis of 153 MDS patients with or without IA who were treated at a single Japanese institute for 10 years. Nineteen of 153 patients (12%) developed autoimmune disorders. One hundred of 153 patients (63%) had an abnormality in at least one immunological laboratory test. Hypergammaglobulinemia was found in 50 of 128 (39%) patients tested, hypogammaglobulinemia was observed in 10 of 128 (8%), positivities of antinuclear antibody, RA factor. DNA antibody, and direct antiglobulin test were observed in 30%, 14%, 7% and 12%, respectively, and a CD4/CD8 ratio < 1 was observed in 20%. There was no significance in the distribution of age, MDS subtype, or sex between patients with and without IA. The survival of MDS patients without IA was significantly better than that of patients with IA, and the survival of patients with a CD4/CD8 ratio > 1 was also significantly superior to the survival of those with an inverted CD4/CD8 ratio. Patients with IA tended to die of infection or leukemic progression in comparison with those without IA, suggesting that IA may be associated with susceptibility to opportunistic infection and disease progression. 相似文献
190.
Koichi Kitazawa Yasuhide Tomioka Toshihiko Nagano Kohji Kishio 《Journal of Superconductivity》1994,7(1):27-31
Comparative studies of Meissner and shielding processes have been performed on variously sized samples of the solid solution (La1–x
Sr
x
)2CuO4: (polycrystalline, powder, and single-crystalline) under various magnetic fields in the range 0.03–10 Oe. Considering the kinetics of the two processes, this systematic approach has indicated that the observed Meissner signal can be significantly low with the sample still being wholly superconductive. Based on this comparative study, the tetragonal region of (La1–x
Sr
x
)2CuO4 withx greater than 0.105 has been concluded to be superconductive, suggesting the nonessential involvement of the buckling of the Cu-O-Cu-O bond in the CuO2 layer in the manifestation of superconductivity. 相似文献