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71.
Summary Retention behavior of anions and cations on anion-exchangers modified with dextran sulfate has been investigated. Retention
of anions was remarkably reduced by the modification, and the retention factor decreased with decreasing eluent concentration
when sodium sulfate was used as the eluent. Cations were also retained on the modified stationary phase, and alkali and alkaline-earth
metal ions were separated using copper sulfate or tris(2,2′-bipyridyl)ruthenium chloride as eluent. The size of the dextran
sulfate strongly affected the retention behavior of analyte ions. 相似文献
72.
Inorganic anions could be separated on porous graphitic carbon stationary phases in ion chromatography. Ion exchange between eluent anions and sample anions on the stationary phase was confirmed by the retention behavior and the possibility of indirect photometric detection. The elution order of anions was different from that observed for commercially available anion exchangers. Chloride, nitrate, and sulfate contained in tap water could be determined in 7 min. 相似文献
73.
74.
Corrugated paper is produced by gluing three types of papers of the same breadth. Given a set of orders, we first assign each order to one of the standard breadths, and then sequence those assigned to each standard breadth so that they are continuously manufactured from the three rolls of the specified standard breadth equipped in the machine called corrugator. Here we are asked to achieve multi-goals of minimizing total length of roll papers, total loss of papers caused by the differences between standard breadths and real breadths of the orders, and the number of machine stops needed during production. We use integer programming to assign orders to standard breadths, and then develop a special purpose algorithm to sequence the orders assigned to each standard breadth. This is a first attempt to handle scheduling problems of the corrugator machine. 相似文献
75.
76.
77.
Noguchi M Nakamura M Ohno A Tanaka T Kobayashi A Ishihara M Fujita M Tsuchida A Mizuno M Shoda S 《Chemical communications (Cambridge, England)》2012,48(45):5560-5562
An efficient chemo-enzymatic process for construction of the α-linked disaccharide unit (GlcNAcα1-4Gal) found in gastric mucin has been developed. The process consists of a one-step preparation of a novel triazine type glycosyl donor in water and the subsequent transglycosylation to a galactose derivative catalysed by α-N-acetylglucosaminidase. 相似文献
78.
Femtosecond two-photon stereo-lithography 总被引:7,自引:0,他引:7
M. Miwa S. Juodkazis T. Kawakami S. Matsuo H. Misawa 《Applied Physics A: Materials Science & Processing》2001,73(5):561-566
We report herein a method for the three-dimensional (3D) fabrication of microstructures by means of direct fs-beam writing
(scanning) inside a polymerizable resin. Photopolymerization takes place via two-photon absorption (TPA), as indicated by
measurements of transmission power dependence. This concept of fabrication is based on two principles: the use of short, sub-picosecond
pulses and simultaneous tight focusing (numerical aperture, NA>1). This approach creates a unique opportunity for avoiding
self-focusing even at very high intensities, as the power is lower than the self-focusing threshold. Under such conditions,
no filament formation takes place and no thermal convection disturbance occurs in the focal vicinity during photo-polymerization.
This technique requires no sacrificial layers or structures in real 3D micro-stereo-lithography.
Received: 31 May 2001 / Accepted: 6 June 2001 / Published online: 30 August 2001 相似文献
79.
Kazuhiko Tsukagoshi Miwa Otsuka Yukihiro Shikataand Riichiro Nakajima 《Journal of chromatography. A》2001,930(1-2):165-169
Peak areas, peak heights, and apparent theoretical plate numbers were examined as a function of sample injection times by use of the batch-type CL detection cell. Comparing the experimental data with those obtained by absorption detector, some considerations were carried out about the peak shape. The peak shape in CL detection was influenced by not only concentration distribution of sample in a sample zone but also sample diffusion and CL reaction at the capillary outlet. The sample injection time of ca. 35 s was recommended for the present CE with CL detector. The injection time much influenced peak shape as well as sensitivity in the CL detection cell. 相似文献
80.
Choji Kashima Yoshihiro Tsukamoto Yohei Miwa Kohei Higashide 《Journal of heterocyclic chemistry》2001,38(3):601-606
The enantioselective reduction of ketones was accomplished by borane in the presence of pyrazole derivatives, particularly 2‐methoxymethyl‐3‐phenyl‐1‐menthopyrazole (8). The catalysis of zinc chloride makes it possible to lower the reaction temperature below 0 °C, and to promote enantioselectivity. 相似文献