High speed and reproducible analysis of nitrosamines by capillary electrophoresis with a sulfonated capillary

Recently environmental control is regarded as important for good human health conditions, and toxic substances, including carcinogens and endocrine disruptors should be eliminated from our living environment. Hence easy quantitative methods are expected for a high level of environmental control. Our previous paper describes an easy quantitative analysis of nitrosamines (NAs) by capillary electrophoresis with an untreated fused silica capillary installed in an ordinary apparatus. In this paper, utilizing a novel type capillary column having sulfonated inner wall was investigated for improvements of separation performance and reproducibility. A sulfonated capillary causes fast and stabile electroosmotic flow because its inner wall is strongly negative charged. On a performance comparison of a sulfonated capillary with an untreated fused silica, analysis time reduction of c.a. forty percent was achieved, and relative standard deviations of migration times and peak responses were less than one third. In addition sample concentrations giving detection and quantitation limits were also reduced to a half.     

Fabrication of vertically aligned diamond whiskers from highly boron-doped diamond by oxygen plasma etching

Conductive diamond whiskers were fabricated by maskless oxygen plasma etching on highly boron-doped diamond substrates. The effects of the etching conditions and the boron concentration in diamond on the whisker morphology and overall substrate coverage were investigated. High boron-doping levels (greater than 8.4 × 10(20) cm(-3)) are crucial for the formation of the nanosized, densely packed whiskers with diameter of ca. 20 nm, length of ca. 200 nm, and density of ca. 3.8 × 10(10) cm(-2) under optimal oxygen plasma etching conditions (10 min at a chamber pressure of 20 Pa). Confocal Raman mapping and scanning electron microscopy illustrate that the boron distribution in the diamond surface region is consistent with the distribution of whisker sites. The boron dopant atoms in the diamond appear to lead to the initial fine column formation. This simple method could provide a facile, cost-effective means for the preparation of conductive nanostructured diamond materials for electrochemical applications as well as electron emission devices.     

Novel Components of the Sex Pheromones Produced by Emerald Moths: Identification,Synthesis, and Field Evaluation

The subfamily Geometrinae (Lepidoptera: Geometridae) includes many species called emerald moths. Based on our recent finding of novel polyenyl compounds, including a double bond at the 12-position from two geometrine species, Hemithea tritonaria and Thalassodes immissaria intaminata, (6Z,9Z,12Z)-6,9,12-trienes and (3Z,6Z,9Z,12Z)-3,6,9,12-tetraenes with a C₁₇–C₂₀ straight chain were synthesized and analyzed by GC-MS. The 6,9,12-trienes, which were prepared by a double Wittig reaction between two alkanals and an ylide derived from (Z)-1,6-diiodo-3-hexene, characteristically produced fragment ions at m/z 79, 150, and M–98. The 3,6,9,12-tetraenes, which were prepared by a coupling between (Z)-3-alkenal and an ylide derived from (3Z,6Z)-1-iodo-3,6-nonadiene, showed fragment ions at m/z 79, 148, and M–96. These diagnostic ions were useful to distinguish these compounds from other known polyenyl pheromones, such as 4,6,9- and 6,9,11-trienes and 1,3,6,9-tetraenes. With reference to the GC-MS data, pheromone extracts of other species in Geometrinae inhabiting the Iriomote Islands were analyzed, and the 6,9,12-trienes were identified in the pheromone gland extracts of Pamphlebia rubrolimbraria rubrolimbraria and Maxates versicauda microptera. Furthermore, a field evaluation of the synthetic polyenes in a mixed forest of Tokyo revealed the following new male attractants for emerald moths: Idiochlora ussuriaria by a C₁₇ 6,9,12-triene and Jodis lactearia by a C₂₀ 3,6,9,12-tetraene, indicating the characteristic chemical structures of Geometrinae pheromones. On the other hand, through reexamination of the pheromone extract of H. tritonaria, (3E,6E)-α-farnesene was identified as an electrophysiologically active component in addition to the C₁₇ 6,9,12-triene. The binary mixture attracted more males than the single component lure baited with the triene in the Iriomote Islands.     

Formation and Structure of Lignin in Monocotyledons. III. Heterogeneity of Sugarcane (Saccharum officinarum L.) Lignin with Respect to the Composition of Structural Units in Different Morphological Regions

Heterogeneity of sugarcane lignin with respect to the composition of structural units in different morphological regions was studied by microautoradiography and some degradative analyses. Structure of the lignin differs among fiber, vessel and parenchyma. The lignin in the secondary wall of fiber is composed of syringyl (S)-, guaiacyl (G)- and p-hydroxyphenyl (H)-propane units with accompanying phenolic acid residues, and the proportion of these monolignols is S > G > H. The lignin in vessels of protoxylem contains more G and H units than S units, and that in vessels of metaxylem is similar to that in fibers. Phenolic acid constituent in sugarcane cell wall includes sinapic acid in addition to p-coumaric and ferulic acids. Ferulic acid deposits at the very early stage of lignification, and p-coumaric and sinapic acids increasingly deposit with the progress of lignification. Therefore, the ratio of p-coumaric acid or sinapic acid to ferulic acid increases with lignification. Parenchyma wall involves larger amount of phenolic acids than vascular bundle does. The lignin in parenchyma is difficult to isolate by Björkman procedure, because there is greater possibility to form cross-linkage among cell wall polymers through phenolic acids. The cross linkages involving phenolic acid ester also explains why the sugarcane lignin is easily degraded.     

Multiple microscale plasma CVD apparatuses on a substrate

Plasma chemical vapor depositions (CVD) of carbon films using a CH₄---H₂ gas system have been performed with a prototype 2×2 plasma chip which consists of 2×2 coplanar film electrodes (CFE). Using this chip, we could perform four plasma processing experiments simultaneously. A plasma chip on which plasma-processing apparatuses are integrated has advantages in plasma processing compared to conventional ones, such as high processing speed due to the high density of the microscale plasma, and high efficiency due to parallel processing. We have obtained various carbon films easily, such as glassy carbon and diamond-like carbon, with this simple prototype plasma chip. This is the first report on plasma processing with this innovative processing device, the plasma chip.     

Decoupling torque control system for automotive engine tester

This paper presents a novel decoupling control method for the engine torque control of an automobile engine tester. The engine tester is mainly composed of a dynamometer control system and an engine control system. The conventional engine tester has the problem that the performance of the engine torque control system is deteriorated by the influences of the interference between the dynamometer speed control system and the engine torque control system. The authors proposed the practical engine torque control system based on an observer and an identification system to eliminate the interference of the dynamometer speed control system. The effect of observer's parameter error on the engine torque estimation response was analyzed. According to the result of this analysis, a practical method is proposed to identify the engine inertia moment and the shaft spring coefficient that are parameters of the observer. The authors confirmed through simulation and experiments that the proposed decoupling engine torque control system realizes a robust control system from the interference with the dynamometer speed control system     

Purification of metallurgical silicon up to solar grade

A new production process of solar-grade silicon (SOG-Si) for small demand which is made from metallurgical-grade silicon (MG-Si) is proposed here, based on the findings of silicon refining stage in NEDO (New Energy and Industrial Technology Development Organization) Direct Reduction Process. SOG-Si trially produced was made into a multicrystalline cell through NEDO Project and the conversion efficiency was max. 10.9%.     

Pharmacokinetic analysis of intra-peritoneal administration of cisplatin]

OBJECTIVE: To compare the 1997 American Diabetes Association (ADA) and the 1980-1985 World Health Organization (WHO) diagnostic criteria in categorization of the diabetes diagnostic status of adults in the U.S. RESEARCH DESIGN AND METHODS: Analyses are based on a probability sample of the U.S. population age 40-74 years in the 1988-1994 Third National Health and Nutrition Examination Survey (NHANES III). People with diabetes diagnosed before the survey were identified by questionnaire. For 2,844 people without diagnosed diabetes, fasting plasma glucose was obtained after an overnight 9 to < 24-h fast, HbA1c was measured, and a 2-h oral glucose tolerance test was administered. RESULTS: Prevalence of diagnosed diabetes in this age-group is 7.9%. Prevalence of undiagnosed diabetes is 4.4% by ADA criteria and 6.4% by WHO criteria. The net change of -2.0% occurs because 1.0% are classified as having undiagnosed diabetes by ADA criteria but have impaired or normal glucose tolerance by WHO criteria, and 3.0% are classified as having impaired fasting glucose or normal fasting glucose by ADA criteria but have undiagnosed diabetes by WHO criteria. Prevalence of impaired fasting glucose is 10.1% (ADA), compared with 15.6% for impaired glucose tolerance (WHO). For those with undiagnosed diabetes by ADA criteria, 62.1% are above the normal range for HbA1c compared with 47.1% by WHO criteria. Mean HbA1c is 7.07% for undiagnosed diabetes by ADA criteria and 6.58% by WHO criteria. CONCLUSIONS: The number of people with undiagnosed diabetes by ADA criteria is lower than that by WHO criteria. However, those individuals classified by ADA criteria are more hyperglycemic, with higher HbA1c values and a greater proportion of values above the normal range. This fact, together with the simplicity of obtaining a fasting plasma glucose value, may result in the detection of a greater proportion of people with undiagnosed diabetes in clinical practice using the new ADA diagnostic criteria.