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Measurements of adsorption-desorption isotherms in a wide temperature range 82-110 K for Kr confined in a cylindrical pores of SBA-15 with a mean radius of 3.2 nm and measurements of adsorption isotherms and X-ray diffraction patterns in a temperature range 80-92 K are performed to examine the relationship between the adsorption isotherm and the freezing behavior of a confined Kr. Hysteresis loops in the whole temperature range examined are observed.

The paper deals with the method of tool path generation for 5-axis control machining using a ball end mill. 5-axis control machining has been used for aircraft parts as well as for complicated shapes such as mold and dies. However, most of the present CAM systems for 5-axis control machining have limited functions in terms of tool collision, workpiece shapes and machining methods. For that reason, in many cases the optimal cutter location (CL) data cannot be obtained or considerable time is consumed. To solve this problem, we applied a 3-dimensional configuration space (C-Space) and showed the relationship between all tool positions and postures and the existence of tool collision. The method of tool path generation devised in the study enables users to generate CL data reflecting their own machining strategy such as smooth change in tool posture and the state of machining without considering the gouging. The validity of this method was experimentally confirmed by successfully milling an impeller without tool collision occurring.

The structures and melting of n-butanol and n-pentanol monolayers adsorbed on graphite have been studied by x-ray diffraction. The structures of both monolayers change between partial and complete monolayers. The complete monolayer of butanol, as well as the partial monolayer of pentanol, take herringbone structures similar to those of butane and hexane monolayers and have zigzag chains of hydrogen bonds. Two-dimensional smectic liquid crystals are formed in melting processes of the complete monolayers of both molecules while the partial monolayers melt directly into liquids. In the mesophases their solid structures are essentially maintained. The results are compared with those of the monolayers of shorter linear-chain alcohol molecules and the effect of molecular length on the melting behavior is discussed. © 1995 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The pressure-volume isotherm and x-ray diffraction measurements for the coadsorption systems of krypton with methanol and ethanol on graphite have been carried out at 77 K. On graphite krypton and methanol are miscible while krypton and ethanol are immiscible. The two-dimensional solid solution of krypton and methanol takes an incommensurate triangular structure with an intermolecular distance ∼4.10 Å and a molar composition Kr/CH3OH ∼0.6. Krypton adsorbed on top of the preadsorbed ethanol monolayer forms a triangular monolayer, incommensurate with the structure of the underlying monolayer. © 1995 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The x-ray diffraction measurements of 2-propanol adsorbed on graphite have been taken over the temperature range 150–240 K and the coverage range 2.28–4.23 molecules/nm2. The analysis of the data by means of the least-squares fitting of the complete pattern suggests that 2-propanol dimers bound by hydrogen bonding are arranged to give a lamellar structure of the molecules on the surface. The melting of the solid monolayers occurs by a two-step process involving an intermediate phase, possibly a defective two-dimensional smectic liquid crystal. The results are compared with the melting behavior observed for the monolayers of n-propanol. [ABSTRACT FROM AUTHOR]

The x-ray diffraction measurements of methanol adsorbed on graphite have been taken over the temperature range 32–150 K and the coverage range 0.02–0.17 molecule Å-2. The diffraction data are analyzed to yield the configuration of the molecule on the surface by means of the least-squares fitting of the whole pattern. The data show clearly that zigzag chains of alternating weak and strong hydrogen bonds, as evidenced by the long and short 0···0 separations, are formed in the crystalline monolayer of methanol on graphite. The crystalline solid film near the complete monolayer melts around 142 K in comparison to bulk methanol which melts at 175.4 K. [ABSTRACT FROM AUTHOR]

X-ray scattering has been used to investigate the structures and phase transitions of Xe and Kr films adsorbed on the basal plane of NiCl2. The x-ray scattering measurements were carried out both as a function of temperature at fixed coverage and as a function of coverage at fixed temperature in the monolayer and bilayer coverage regimes. The results indicate that both the monolayers of Xe and Kr adsorbed on the basal plane of NiCl2 form a 2D solid of the simple triangular structure incommensurate with the substrate and 2D melting is first order in the incommensurate solid of Xe but continuous in that of Kr. With the addition of the second-layer atoms the interparticle distance of the adsorbed atoms reduces and the crystallinity of the incommensurate solid improves. [ABSTRACT FROM AUTHOR]

Examines the effect of temperature on adsorption isotherms of argon, nitrogen[sub 2], oxygen, carbon[sub 2]hydrogen[sub 4], and carbon dioxide on model mesoporous adsorbents with different pore sizes. Shrinkage of the hysteresis loop; Absence of the adsorption hysteresis in the cylindrical pore small radius; Linkage of irregular pores to the data points.

Studies the freezing/melting behavior of pore water using x-ray diffraction measurements of water confined inside the cylindrical pores of two kinds of siliceous MCM-41. Effect of the incorporation of aluminum into the power all; Diffraction profile after the freezing of the free water.

Background and aim: Sessile serrated adenoma/polyps (SSAPs) are suspected to have a high malignant potential, although few reports have evaluated the incidence of carcinomas derived from SSAPs using the new classification for serrated polyps (SPs). The aim of study was to compare the frequency of cancer coexisting with the various SP subtypes including mixed polyps (MIXs) and conventional adenomas (CADs). Methods: A total of 18,667 CADs were identified between April 2005 and December 2011, and 1858 SPs (re-classified as SSAP, hyperplastic polyp (HP), traditional serrated adenoma (TSA), or MIX) were removed via snare polypectomy, endoscopic mucosal resection, or endoscopic sub-mucosal dissection. Results: Among 1160 HP lesions, 1 (0.1 %) coexisting sub-mucosal invasive carcinoma (T1) was detected. Among 430 SSAP lesions, 3 (0.7 %) high-grade dysplasia (HGD/Tis) and 1 (0.2 %) T1 were detected. All of the lesions were detected in the proximal colon, with a mean tumor diameter of 18 mm (SD 9 mm). Among 212 TSA lesions, 3 (1 %) HGD/Tis were detected but no T1 cancer. Among 56 MIX lesions, 9 (16 %) HGD/Tis and 1 (2 %) T1 cancers were detected, and among 18,677 CAD lesions, 964 (5 %) HGD/Tis and 166 (1 %) T1 cancers were identified. Conclusions: Among the resected lesions that were detected during endoscopic examination, a smaller proportion (1 %) of SSAPs harbored HGD or coexisting cancer, compared to CAD or MIX lesions. Therefore, more attention should be paid to accurately identifying lesions endoscopically for intentional resection and the surveillance of each SP subtype. [ABSTRACT FROM AUTHOR]