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排序方式: 共有2205条查询结果,搜索用时 343 毫秒
991.
Hiromi Yamashita Shinichi Kawasaki Shuai Yuan Kazuhiro Maekawa Masakazu Anpo Michio Matsumura 《Catalysis Today》2007,126(3-4):375-381
Using the F− media, the hydrophobic zeolite and mesoporous silica can be synthesized. These hydrophobic porous materials exhibit the high ability for the adsorption of organic compounds diluted in water and become the useful supports of photocatalyst. The hydrophobic Ti-Beta(F) zeolite prepared in the F− media exhibited high efficiency than the hydrophilic Ti-Beta(OH) zeolite prepared in OH− media for the liquid-phase photocatalytic degradation of 2-propanol diluted in water to produce CO2 and H2O. The TiO2 loaded on the hydrophobic mesoporous silica HMS(F) (TiO2/HMS(F)), which was synthesized using tetraethyl orthosilicate, tetraethylammonium fluoride as the source of the fluoride and dodecylamine as templates, also exhibited the efficient photocatalytic performance for the degradation. The amount of adsorption of 2-propanol and the photocatalytic reactivity for the degradation increased with increasing the content of fluoride ions on these photocatalysts. The efficient photocatalytic degradation of 2-propanol diluted in water on Ti-Beta(F) zeolite and TiO2/HMS(F) mesoporous silica can be attributed to the larger affinity for the adsorption of propanol molecules on the titanium oxide species depending on the hydrophobic surface properties of these photocatalysts. 相似文献
992.
Bisphenol-A type and biphenyl type epoxide resins were cured with two types of aromatic diamines which have or do not have the carbon bridge between aromatic rings. Internal stress of these cured resins decreased with the introduction of a biphenyl structure into the networks. This reduction of the internal stress is attributed to the decrease of the elastic modulus in the glassy region caused by the low mobility of the biphenyl segment. On the other hand, the glass transition temperature increased with increasing the concentration of the biphenyl unit in the networks. These results revealed that the consistency of the decrease of the internal stress with the improvement of the heat resistance of the cured systems is possible by introducing the biphenyl structure to the epoxide resin networks. 相似文献
993.
Nobuharu Tamaki Masayuki Kurosaki Yuka Takahashi Yoshie Itakura Sakura Kirino Kento Inada Koji Yamashita Shuhei Sekiguchi Yuka Hayakawa Leona Osawa Mayu Higuchi Kenta Takaura Chiaki Maeyashiki Shun Kaneko Yutaka Yasui Kaoru Tsuchiya Hiroyuki Nakanishi Jun Itakura Rohit Loomba Namiki Izumi 《International journal of molecular sciences》2021,22(1)
Chronic liver disease is generally widespread, and a test for screening fibrotic subjects in a large population is needed. The ability of Wisteria floribunda agglutinin-positive mac-2 binding protein (WFA+-M2BP) to detect significant fibrosis was investigated in health checkup subjects in this research. Of 2021 health checkup subjects enrolled in this prospective cross-sectional study, those with WFA+-M2BP ≥ 1.0 were defined as high risk. Liver fibrosis was evaluated using magnetic resonance elastography (MRE) in subjects with high risk. The primary outcome was the positive predictive value (PPV) of WFA+-M2BP for significant fibrosis (liver stiffness ≥ 2.97 kPa by MRE). This trial was registered with the UMIN clinical trial registry, UMIN000036175. WFA+-M2BP ≥ 1.0 was observed in 5.3% of the 2021 subjects. The PPV for significant fibrosis with the threshold of WFA+-M2BP at ≥1.0, ≥1.1, ≥1.2, ≥1.3, ≥1.4, and ≥1.5 was 29.2%, 36.4%, 43.5%, 42.9%, 62.5%, and 71.4%, respectively. A WFA+-M2BP of 1.2 was selected as the optimal threshold for significant fibrosis among high-risk subjects, and the PPV, negative predictive value, sensitivity, and specificity for significant fibrosis were 43.5%, 84.0%, 71.4%, and 61.8%, respectively. WFA+-M2BP ≥ 1.2 was significantly associated with significant fibrosis, with an odds ratio (OR) of 4.04 (95% confidence interval (CI): 1.1–16, p = 0.04), but not FIB-4 ≥ 2.67 (OR: 2.40, 95%CI: 0.7–8.6, p-value = 0.2). In conclusion, WFA+-M2BP is associated with significant fibrosis and could narrow down potential subjects with liver fibrosis. The strategy of narrowing down fibrosis subjects using WFA+-M2BP may be used to screen for fibrotic subjects in a large population. 相似文献
994.
H Kitagaki E Mori N Hirono Y Ikejiri K Ishii T Imamura M Ikeda S Yamaji H Yamashita T Shimomura Y Nakagawa 《Canadian Metallurgical Quarterly》1997,18(2):367-378
Our material consists of the analysis of the results obtained during the postmortem angiologic research of the brain in a deceased 36-years-old woman treated in Neurosurgical Department of Medical university in Lódz. The patient was diagnosed as follows: Arteriovenous malformation (AVM) in the central region of the brain with giant "aneurysm" of the vein of Gallen. Internal hydrocephalus. The anatomical and angiological investigations were concerned mainly with the vessels of the Willis circle, choroid arteries and their branches both in subarachnoid space and in brain parenchyma--and those regions of the brain where pathological changes were detected angiologically. The reason for the comparative evaluation of the vascular changes was the material prepared earlier in the laboratory and literature data concerning: vascularization od choroid plexus of lateral and III ventricles of the brain and vascular deformities in brains of deceased adult and senile patients. This paper is also an attempt at comparing of the vascular changes in postmortem injection examination to results of radiological studies obtained in living patient (angiography of the internal carotid and vertebral arteries) and CT examination. 相似文献
995.
Yukiya Yamashita Kei Ishiguro Daisuke Nakai Masayoshi Fuji 《Advanced Powder Technology》2018,29(10):2521-2526
The synthesis of a porous-type of TiO2 with rutile structure was studied. The focuses were on the thermal treatment temperature and time. AEROXIDE® TiO2 P 25, as a fumed TiO2, was thermally treated in a vertical-type tubular furnace by the natural dropping method. Even though the thermal treatment time was less than 1?s, a drastic increase of polymorphism from anatase structure to rutile structure was observed. The relationships between the rutile structure transformation ratio and surface area of obtained porous type of TiO2 were investigated depending on the thermal treatment temperature. The porous-type of fumed TiO2 showed high dispersibility in the sedimentation test although is showed large particle size. 相似文献
996.
C Park K Sakamaki O Tachibana T Yamashima J Yamashita S Yonehara 《Canadian Metallurgical Quarterly》1998,252(3):623-628
In this paper, the first of a series dealing with the development of a methodology for assessing quality of ambulatory care, a sample of 270 outpatients from the same health center were presented with a list of 12 questions. Although different versions of the questionnaire were tested, we found a high degree of agreement between the results. The findings indicate that the parameter "satisfaction" lends itself readily to measurement, thus becoming a useful instrument for guiding active intervention. 相似文献
997.
YM Deo K Sundarapandiyan T Keler PK Wallace RF Graziano 《Canadian Metallurgical Quarterly》1998,160(4):1677-1686
The FcR for IgA (Fc alpha RI, CD89) is primarily expressed on cytotoxic immune effector cells. By chemically cross-linking F(ab') fragments of the FcR for IgA (Fc alpha RI)-specific mAb (A77) with tumor Ag-specific mAb (anti-HER2/neu and anti-epidermal growth factor receptor), we have developed bispecific molecules (BSM) that simultaneously bind to respective tumor Ags and Fc alpha RI-expressing effector cells in whole blood. These BSM mediated up to 55% of specific lysis of appropriate tumor Ag-expressing target cells (from a variety of tumors) with purified polymorphonuclear leukocytes, monocytes, or whole blood effector cells without preactivation with exogenous cytokines. To our knowledge, this is the first demonstration of Ab-dependent cell-mediated cytotoxic activity via Fc alpha RI in whole blood. Also, monocyte-derived macrophages mediated phagocytosis of HER2/neu-expressing tumor cells (>95% tumor cell loss). These BSM-mediated cytotoxic activities were completely inhibited by F(ab')2 of A77, demonstrating the specific role of Fc alpha RI as a trigger molecule. Furthermore, the binding of these BSM to monocytes or polymorphonuclear leukocytes in whole blood did not induce modulation of Fc alpha RI in the absence of the target Ag. Therefore, immune effector cells may be "armed" with Fc alpha RI-directed BSM in whole blood. These Fc alpha RI-directed BSM may offer new treatment options for various malignancies and other disease conditions. 相似文献
998.
Wang S. Izaki K. Hirota I. Yamashita H. Omori H. Nakaoka M. 《Industry Applications, IEEE Transactions on》1998,34(4):705-712
This paper presents a new prototype of a voltage-fed quasi-load resonant inverter with a constant-frequency variable-power (CFVP) regulation scheme, which is developed for the next-generation high-frequency high-power induction-heated (IH) cooking appliances in household applications. This application-specific high-frequency single-ended push-pull inverter using new-generation specially designed insulated gate bipolar transistors (IGBTs) can efficiently operate under a principle of zero-voltage switching pulsewidth modulation (ZVS-PWM) strategy. This low-cost soft-switching inverter using reverse-conducting and reverse-blocking IGBTs is more suitable for multiple-burner-type induction-heating cooking appliances. The operating principle and unique features of a new resonant ZVS-PWM inverter circuit topology is originally described, together with its steady-state power regulation characteristics, which are illustrated on the basis of its computer-aided simulation and experimental results. The ZVS operation condition on power regulation, loss analysis of new IGBTs incorporated into this inverter, and its active filtering performance are discussed for IH cooking appliances 相似文献
999.
1000.
Tracking in low frame rate video: a cascade particle filter with discriminative observers of different life spans 总被引:1,自引:0,他引:1
Li Y Ai H Yamashita T Lao S Kawade M 《IEEE transactions on pattern analysis and machine intelligence》2008,30(10):1728-1740
Tracking object in low frame rate video or with abrupt motion poses two main difficulties which most conventional tracking methods can hardly handle: 1) poor motion continuity and increased search space; 2) fast appearance variation of target and more background clutter due to increased search space. In this paper, we address the problem from a view which integrates conventional tracking and detection, and present a temporal probabilistic combination of discriminative observers of different lifespans. Each observer is learned from different ranges of samples, with different subsets of features, to achieve varying level of discriminative power at varying cost. An efficient fusion and temporal inference is then done by a cascade particle filter which consists of multiple stages of importance sampling. Experiments show significantly improved accuracy of the proposed approach in comparison with existing tracking methods, under the condition of low frame rate data and abrupt motion of both target and camera. 相似文献