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排序方式: 共有609条查询结果,搜索用时 31 毫秒
31.
Kyoungkeun Yoo Soo-kyung Kim Jae-chun Lee Mayumi Ito Masami Tsunekawa Naoki Hiroyoshi 《Minerals Engineering》2010,23(6):471-477
The effect of chloride on chalcopyrite leaching has been investigated by performing batch leaching tests with three kinds of leaching solutions and using Hiroyoshi’s model, which suggests that a zone of rapid leaching exists between the critical potential (Ec, equilibrium redox potential for the reduction of CuFeS2 to Cu2S) and the oxidation potential (Eox, equilibrium redox potential for the oxidation of Cu2S). The results of the leaching tests show that the leaching rate in hydrochloric acid solution is the fastest and that the relationship between the Cu leaching rate and oxidation–reduction potential (ORP) follows Hiroyoshi’s model. Thermodynamic calculations indicate that, with an increase in the chloride concentration, the concentration of cuprous ions increases as the chlorocuprate(I) complex ions are formed and the contribution of cuprous ions to the critical potential is greater than that of cupric ions, even though the concentration of cuprous ions is lower than that of cupric ions. This fact suggests that the formation of chlorocuprate(I) ions in a chloride solution may improve the chalcopyrite leaching rate by increasing the critical potential. 相似文献
32.
S. K. Heeks J. H. Burroughes C. Towns S. Cina N. Baynes N. Athanassopoulou J. C. Carter S. Miyashita 《Journal of the Society for Information Display》2002,10(2):139-143
The latest developments in light‐emitting‐polymer (LEP) technology at CDT continue to show steady progress. Device performance for blue, green, and red systems as well as a high‐performance yellow system in terms of device efficiency and stability will be described. Some of the issues associated with the commercialization of LEP technology including the development of direct‐patterning techniques enabling full‐color passive‐ and active‐matrix display will be discussed. 相似文献
33.
We propose a method that incorporates the time-frequency characteristics of neural sources into magnetoencephalographic (MEG) source estimation. The method is based on the multiple-signal-classification (MUSIC) algorithm and it calculates a time--frequency matrix in which diagonal and off-diagonal terms are the auto and crosstime--frequency distributions of multichannel MEG recordings, respectively. The method averages this time-frequency matrix over the time--frequency region of interest. The locations of neural sources are then estimated by checking the orthogonality between the noise subspace of this averaged matrix and the sensor lead field. Accordingly, the method allows us to estimate the locations of neural sources from each time--frequency component. A computer simulation was performed to test the validity of the proposed method, and the results demonstrate its effectiveness. 相似文献
34.
T. Watanabe H. Kashiwagi S. Miyashita N. Ichioka K. Tokiwa A. Iyo Y. Tanaka S.K. Agarwal H. Ihara 《Journal of Low Temperature Physics》1999,117(3-4):753-757
We have synthesized the single phase samples of Cu
x
C
0.1
Ba
2
Ca
3
Cu
4
O
z
(x=0.20.9). Transport and magnetic measurements and iodometric titration analysis were carried out for these materials. From these results we discuss the correlation between T
c
, the Hall number, copper valence and oxygen content. The effect of the substituted M ions on T
c
in (CuC, M)-l234 (M=Ni,Zn,Al,TI,Mg) is also discussed. We propose a unique selective carrier-doping mechanism in (Cu,C)- and (CuC,Mg)-1234 systems. 相似文献
35.
Okada H. Miyamukai N. Shibata M. Onnagawa H. Kodoh Y. Miyashita K. 《Electronics letters》1995,31(13):1099-1100
Video rate optical transmission at room temperature (RT) for smectic liquid crystal light modulators (SLCLMs) and filter circuits has been demonstrated. The bandwidth of this system has been determined to be 5.6 MHz. Optical transmission of the National Television System Committee (NTSC) video signal at RT has been realised 相似文献
36.
M Hisada T Fujita H Naoki Y Itagaki H Irie M Miyashita T Nakajima 《Canadian Metallurgical Quarterly》1998,36(8):1115-1125
Facile structure determination of acylpolyamines, glutamatergic nerve blocker obtained from the venom of the Joro spider (Nephila clavata) was carried out with the use of micro-column LC/MS and high energy collision induced dissociation (CID) mass spectrometry. 6-hydroxyindole-3-acetyl was proposed previously as a putative partial structure, for the acyl moiety of hydroxyindole-type polyamines (NPTX-1 to -6). The NMR data obtained for NPTX-6, NPTX-687 and hydroxyindole-3-acetic acid which was released by acid hydrolysis of Nephila clavata crude venom extracts proved that the lipophilic head is the 4-hydroxyindole-3-acetic acid. Various hydroxyindole-3-acetyl polyamines were found in N. Clavata venom and characterized by mass spectrometry. As a result, type-E, a new class of generalized acylpolyamine structure was proposed in addition to the previously reported polyamine backbones type-A to -D. 相似文献
37.
G Bullock S Ray J Reed T Miyashita A Maria Ibrado Y Huang K Bhalla 《Canadian Metallurgical Quarterly》1995,1(5):559-564
Previous reports have demonstrated that a variety of anticancer drugs, e.g., 1-beta-D-arabinofuranosylcytosine (ara-C), mitoxantrone, etoposide, camptothecin, and cisplatin, induce the expression of c-jun oncogene in leukemic cells prior to producing internucleosomal DNA fragmentation and the morphological features of apoptosis. This has led to the impression that the induction of c-jun expression may be directly involved in the molecular signaling of the final common pathway of programmed cell death or apoptosis. In the present study, we examined the role of c-jun expression in three different settings of anticancer drug-induced apoptosis in human leukemic cells. First, exposure of human myeloid leukemia HL-60 cells to high-dose ara-C for 4 h produced internucleosomal DNA fragmentation preceded by c-jun induction. However, pretreatment of HL-60 cells with staurosporine, a protein kinase C inhibitor, repressed c-jun yet enhanced DNA fragmentation and apoptosis due to ara-C. Second, in human pre-B leukemia 697/BCL-2 cells which are transfected with the cDNA of the bcl-2 oncogene and overexpress p26BCL-2, although ara-C or mitoxantrone treatment caused greater c-jun induction than in the 697/neo cells, significantly reduced endonucleolytic DNA fragmentation and apoptosis was observed in 697/BCL-2 cells. Finally, taxol-induced internucleosomal DNA fragmentation and morphological features of apoptosis in HL-60 cells were not associated with the induction of c-jun expression. These lines of evidence indicate that the induction of c-jun expression may not have a direct role in the molecular signaling of anticancer drug-induced apoptosis, and that the anticancer drug-induced apoptosis can occur by a mechanism that does not involve the induction of c-jun expression. 相似文献
38.
39.
40.
Low-loss single-mode fibres with GeO2-doped SiO2 cores have been made by the c.v.d. method and the loss spectrum from 0.6 to 1.8 ?m measured. The minimum loss of the fibre with suitably designed parameters, characterised by the refractive-index difference and the core diameter, was 0.75 dB/km at 1.05 ?m. 相似文献