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排序方式: 共有332条查询结果,搜索用时 15 毫秒
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H Tomoda M Hoshiai R Tagawa S Koide S Kawada A Shotsu S Matsuyama 《Canadian Metallurgical Quarterly》1980,100(3):306-310
Left atrial thrombi were evaluated with computed tomography in 23 patients with mitral valvular diseases. In three of the patients, left atrial thrombi were delineated with computed tomography and were confirmed by cardiac surgery or autopsy. The minimum size of the thrombi detected tomographically was 3.5 gm. There were no false-positive or false-negative results with computed tomography in 13 patients who subsequently underwent cardiac surgery. Computed tomography is essentially noninvasive and appears to be one of the best methods to evaluate left atrial thrombus. 相似文献
14.
On the basis of the mathematical notion of “micro-macro duality” for understanding mutual relations between microsopic quantum
systems (micro) and their macroscopic manifestations (macro) in terms of the notion of sectors and order parameters, a general
mathematical scheme is proposed for detecting the state-structure inside of a sector through measurement processes of a maximal
abelian subalgebra of the algebra of observables. For this purpose, the Kac-Takesaki operators controlling group duality play
essential roles, which naturally leads to the composite system of the observed system and the measuring system formulated
by a crossed product. This construction of composite systems will be shown to make it possible for the micro to be reconstructed
from its observational data as macro in the light of the Takesaki duality for crossed products. 相似文献
15.
Misao Koide Jinta Ukawa Waichiro Tagaki Seizo Tamagaki 《Journal of the American Oil Chemists' Society》1997,74(1):49-54
Two different types of methyl esters of β-glycyrrhizinate (GK2) have been prepared to delineate the mechanism of the catalytic
action of each carboxyl group of GK2 in the hydrolysis of nonionic fatty acid surfactants. In the acidic pH region of less
than 4, the hydrolysis is catalyzed by the carboxyl groups of the sugar moiety, while in the close-to-neutral acidic region,
the carboxyl group at the hydrophobic triterpenoid end becomes important in catalysis. 相似文献
16.
This paper presents a new chip control method with guide grooves formed on the rake face to realize continuous chip disposal and chip-pulling turning. Chips are conventionally broken using chip breakers during turning operations for disposal. However, chips of highly ductile materials or thin chips generated in finishing can not be broken easily. In order to prevent the chips from jamming up, the authors propose to continuously guide the chips away from the cutting point. Special tool tips were developed and tested for guiding the chip. Chip controllability and mechanics of the chip-guided cutting are discussed in the present research. 相似文献
17.
Evert‐Jan van Donkelaar Juergen Schultze Toru Shibuya Yutaka Konai Mitsuharu Miyazaki 《Journal of the Society for Information Display》2002,10(3):223-229
In 1998, Toyo Gosei Co. published a paper on the development of a new water‐soluble photopolymer of high sensitivity, PVA‐ARBB. In close co‐operation with LG. Philips Displays, the new material was further developed to be applicable in patterning the phosphor layer of a CRT screen. The new material shows about 3 times higher light sensitivity, gives 4–5% higher luminance, has no dark reaction, and is chromium‐free. It is the first chromium‐free photoresist used for phosphor patterning in CRT mass production. A comparison is presented between the conventional resist and the new resist. A survey is given of the most important process conditions. 相似文献
18.
The proposed stacked GaAs DCFL circuit structure can not only equalise a power supply voltage value (3-5 V) used in Si ICs, but can also reduce circuit current (30-50%) due to current sharing within a stacked circuit. A divide by 128/129 and 64/65 prescalar IC has been fabricated to confirm this concept.<> 相似文献
19.
Yanbo Li Takero Tokizono Meiyong Liao Miao Zhong Yasuo Koide Ichiro Yamada Jean‐Jacques Delaunay 《Advanced functional materials》2010,20(22):3972-3978
An increasing number of applications using ultraviolet radiation have renewed interest in ultraviolet photodetector research. Particularly, solar‐blind photodetectors sensitive to only deep UV (<280 nm), have attracted growing attention because of their wide applicability. Among recent advances in UV detection, nanowire (NW)‐based photodetectors seem promising, however, none of the reported devices possesses the required attributes for practical solar‐blind photodetection, namely, an efficient fabrication process, a high solar light rejection ratio, a low photocurrent noise, and a fast response. Herein, the assembly of β‐Ga2O3 NWs into high‐performance solar‐blind photodetectors by use of an efficient bridging method is reported. The device is made in a single‐step chemical vapor deposition process and has a high 250‐to‐280‐nm rejection ratio (~2 × 103), low photocurrent fluctuation (<3%), and a fast decay time (<<20 ms). Further, variations in the synthesis parameters of the NWs induce drastic changes in the photoresponse properties, which suggest a possibility for tuning the performance of the photodetectors. The efficient fabrication method and high performance of the bridged β‐Ga2O3 NW photodetectors make them highly suitable for solar‐blind photodetection. 相似文献
20.
H Shimada K Nakajima T Ochiai Y Koide SI Okazumi H Matsubara A Takeda Y Miyazawa M Arima K Isono 《Canadian Metallurgical Quarterly》1998,5(4):871-874
The significance of serum p53-Abs in patients with esophageal squamous cell carcinoma was determined. Examination of clinicopathological features and assessment of tumor marker sensitivities of carcinoembryonic antigen (CEA), squamous cell carcinoma antigen (SCC-Ag) and CYFRA21-1 were performed. Thirty-three (58%) of 57 patients were positive for serum p53-Abs, however, no relation with cancer progression existed. Fourteen of the 33 sero-positive patients revealed normal levels of all tumor markers tested. Thus, serum p53-Abs appears to be a useful marker for the detection of esophageal squamous cell carcinoma. 相似文献