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131.
The novel N-terminal labeling method using a ruthenium(II) complex derivative characteristically indicated a(n) and d(n) (N-terminal) fragment ions in high sensitivity by MS/MS analysis (MALDI-LIFT or ESI-CID). Although these fragment ions depended on a fragmentation process by MS/MS analytical methods to some degree, each case indicated similar side-chain cleavage patterns. The labeling method allows accurate distinction of amino acid residues by MS/MS analysis even if the residues are structural isomers such as leucine and isoleucine. The method was applied to long-chain peptides and provided easy and rapid N-terminal sequencing.  相似文献   
132.
Various countries have established regulations that stipulate the labeling of agricultural commodities, feed, and food products that contain or are made from genetically modified (GM) material or that contain adventitious GM material in amounts that exceed certain threshold levels. While regulations in some countries refer to GM material on a weight per weight (w/w) percentage, the currently applied detection methods do not directly measure the w/w percentage of the GM material. Depending on the particular method and the sample matrix it is applied to, the conversion of analytical results to a w/w percentage is challenging or not possible. The first rapid PCR system for GM maize detection on a single kernel basis has been developed. The equipment for the grinding of individual kernels and a silica membrane-based 96-well DNA extraction kit were both significantly revised and optimized for this particular purpose, respectively. We developed a multiplex real-time PCR method for the rapid quantification of GM DNA sequences in the obtained DNA solutions. In addition, a multiplex qualitative PCR detection method allows for the simultaneous detection of different GM maize traits in each kernel and thereby for identification of individual kernels that contain a combination of two or more GM traits. Especially for grain samples that potentially contain combined-trait GM maize kernels, the proposed methods can deliver informative results in a rapid, precise, and reliable manner.  相似文献   
133.
Ion-beam milling has been used to produce thin-foils of hardened cement paste for examination in an analytical scanning transmission electron microscope (STEM). Resin impregnation has been usefully employed to support delicate microstructure, especially that of young pastes, so that cross-sections of hydrating cement grains can be examined. The morphologies observed in STEM are similar to those observed in conventional scanning electron microscope (SEM) studies.  相似文献   
134.
The present study investigated a novel milling method for producing amorphous rice starch without adding water. A new type of milling machine was developed (termed the shear and heat milling machine (SHMM)), which is capable of applying mechanical shear and heat during the milling process. The SHMM consisted of a pair of rice mortars attached to a servomotor and a ring heater. The heater was installed on the upper mortar; the temperature of the upper mortar was monitored and controlled by a thermal controller. Wide‐angle X‐ray diffraction (WAXD) analysis was used to determine the crystallinities of starch in rice flour samples produced using the SHMM at different milling temperatures. The WAXD data for milled rice flour that had been heated exhibited no diffraction peaks. This experimental result demonstrates that the developed SHMM produces amorphous rice starch easily by milling with heating without the addition of water. The milling conditions such as the shear and heat applied can be used to control the crystallinity of starch in rice.  相似文献   
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The quantitative measurement of a crystal bending effect is performed using low-order zone-axis convergent beam electron diffraction (CBED) patterns. Although the accuracy of the present method is inferior to that of the method of using split higher order Laue zone lines, this method enables us to estimate the crystal bending effect at a region very close to the interface and to easily judge whether the crystal bending effect results in a tensile bend or a compressive bend. As an application of the present method, the crystal bending effect at a region close to the SiGe/Si interface was measured. It was found that the crystal bending effect is due to a thin-foil relaxation of almost 0.3 degrees at a region that is approximately 10 nm away from the interface.  相似文献   
137.
The small punch creep (SPC) test is considered as a highly useful method for creep life assessment for high temperature plant components. SPC uses miniature-sized specimens and does not cause any serious sampling damages, and its assessment accuracy is at a high level. However, in applying the SPC test to the residual creep life assessment of the boiler in service, there are some issues to be studied. In order to apply SPC test to the residual creep life assessment of the 2.25Cr–1Mo steel boiler pipe, the relationship between uniaxial creep stress and the SPC test load has been studied.  相似文献   
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