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101.
A new optical CO2 sensor based on the overlay of the CO2 induced absorbance change of pH indicator dye α-naphtholphthalein with the fluorescence of tetraphenylporphyrin (TPP) was developed. The observed luminescence intensity from TPP at 655 nm increased with increasing the CO2 concentration. The ratio I100/I0 values of the sensing films consisting of α-naphtholphthalein in ethyl cellulose layer and TPP in polystyrene layer, where I0 and I100 represent the detected luminescence intensities from a layer exposed to 100% nitrogen and 100% CO2, respectively, that the sensitivity of the sensor, are more than 53.9. The response and recovery times of the sensing films consisting of α-naphtholphthalein in ethyl cellulose layer and TPP in polystyrene layer were less than 5 s for switching from nitrogen to CO2, and for switching from CO2 to nitrogen. The signal changes were fully reversible and no hysterisis was observed during the measurements. The highly sensitive optical CO2 sensor based on fluorescence intensity changes of TPP due to the absorption change of α-naphtholphthalein with CO2 was achieved. 相似文献
102.
Suga K Mochizuki N Harayama K Yamashita H 《Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan》2004,45(6):307-312
A simple method for analysis of trichothecenes [Type A: diacetoxyscirpenol, neosolaniol, HT-2 toxin, and T-2 toxin, Type B: deoxynivalenol, nivalenol, fusarenon-X, 3-acetyldeoxynivalenol, 15-acetyldeoxynivarenol] in barley tea and beer using liquid chromatography tandem mass spectrometry (LC/MS/MS) was developed. Trichothecenes were extracted with ethyl acetate-methanol (19:1). The solvent was evaporated to dryness and the residue was dissolved in water-methanol (3:1) for injection into the LC/MS/MS. The LC separation was performed with an octadecylated silica column at a flow-rate of 0.2 mL/min, using a mobile phase consisting of water, methanol and acetonitrile. MS/MS was used in multiple reaction monitoring, employing electrospray ionization (ESI-MRM). The recoveries of trichothecenes from drinks at 1 microg/L (Type A) and 10 microg/L (Type B) were 52.5-115.2% (barley tea) and 68.1-127.5% (beer). Five barley tea and ten beer samples were analyzed by this method. Trichothecenes were not detected in them. This method may have applications in quality assurance. 相似文献
103.
Naoki Takahashi Hiroshi Tujii Megumi Katori Kenji Yamashita Daiji Noda Tadashi Hattori 《Microsystem Technologies》2010,16(8-9):1303-1307
We have produced diffraction gratings for obtaining high resolution X-ray phase imaging, such as X-ray Talbot interferometer. These diffraction gratings were required to have a fine, high accuracy, high aspect ratio structure. Therefore, we decided to use the X-rays lithography technique that used synchrotron radiation of the directivity for a manufacture process. The accuracy of the completed structure depends largely on the accuracy of the X-ray mask. In our group, a resin material is conventionally used for the membrane of large X-ray masks. However, X-ray masks comprising a resin membrane have the disadvantage that, after several cycles of X-ray exposure, they crease and sag due to X-ray-derived heat. As a substitute for the conventional resin membrane, we experimentally fabricated a new X-ray mask using a carbon wafer membrane. The newly fabricated X-ray mask was subjected to X-ray exposure experiment. We succeeded in making the structure body which was almost shape. And the experimental results verified that the new mask did not deteriorate even when used repeatedly, demonstrating that it was highly durable. 相似文献
104.
A novel technique for visualizing ultrasonic waves in general solid media by pulsed laser scan 总被引:2,自引:0,他引:2
This study proposes a novel technique to visualize ultrasonic waves propagated in a general solid medium. A specimen was scanned by a pulsed laser for generation of ultrasound, and the propagated waves were received by a fixed transducer. This technique then provided a snapshot of traveling waves based on the reversibility for the wave propagation, which is confirmed in this paper. We experimentally and numerically investigated and visualized the wave propagation in a steel plate with a slit. Furthermore, we demonstrated inspection of an elbow pipe with an artificial defect, as an application of the proposed technique to a structural component. Non-contact laser scanning for ultrasound excitation enabled us to inspect a wide area of an arbitrarily shaped object. The distinguishing advantages of this technique were determined to be well-suited to the quick and easy wide-range inspection of real structures. 相似文献
105.
Masashi Wada Satoshi Kitaoka Naoki Kawashima Tatsuya Yamada Yoshiyuki Yasutomi Masatoshi Kawai Hideki Inagaki 《Journal of the American Ceramic Society》2006,89(7):2134-2139
Carbon substrates were coated completely with a molten silicate glass, where the wettability of carbon to glass was improved by infiltration and pyrolysis of perhydropolysilazane. Microstructures of the carbon–glass interface were dependent on P n 2 during coating. Coating at lower P n 2 induced the formation of cristobalite at the carbon–glass interface. When the coating was performed at higher P n 2 , the glass and carbon were strongly adhered, without the formation of cristobalite. Coating at higher P n 2 improved the thermal shock resistance of the glass layer, because crack initiation was not induced by the phase transformation of cristobalite during the cooling process. In the case of coating at higher P n 2 , an oxynitride glass layer was formed at the glass subsurface by dissolution of N2 . A porous glass subsurface layer with uniform spherical micro-pores could be produced by soaking near the glass transition temperature in a steam environment. The porous layer with fine and homogeneous microstructure acts as a thermal shock absorbing layer, so that glass-coated carbon with a porous glass layer has excellent thermal shock resistance in addition to steam oxidation resistance. 相似文献
106.
The authors have analysed and evaluated a two-dimensional instruction set of parallel operation based on optical array logic (OAL), which is a digital optical computing paradigm, to clarify efficient composition of an optical computing system based on OAL. To evaluate parallel operation based on OAL, the author have introduced new indices and evaluated a logical instruction set of various parallel operations with the indices, so that a guideline for composing a simple and efficient OAL computing system is clarified. Also, the authors have proposed the reduced operation kernel set correlation technique to perform parallel operations more efficiently by a simple OAL computing system. It has been clarified that the technique can reduce the required hardware necessary for an OAL computing system for efficient general-purpose processing. 相似文献
107.
BACKGROUND: High aerobic stability can be expected when wet brewers' grains are stored as a total mixed ration (TMR) silage. To understand the factors affecting the stability, the effects of ration formulation, air infiltration and storage period were studied. RESULTS: A TMR containing wet brewers' grains, hay, maize, wheat bran, beet pulp and molasses was ensiled in laboratory silos for 14 and 56 days. The effects of hay species (lucerne or sudangrass) and air infiltration (Exp. 1) and of excluding one, two or three items from the six ingredients (Exp. 2) were examined. Ethanol was the main fermentation product in all TMR silages in this study. Aerobic deterioration occurred in 14 day silages prepared with sudangrass hay along with air infiltration (Exp. 1), and with the simplest recipe where three items (hay, maize and wheat bran) were excluded (Exp. 2). No deterioration occurred in 56 day silages regardless of ration formulation and air infiltration. Yeasts receded in 56 day silages, except with the simplest recipe, to the 102 cfu g?1 level and remained undetectable in the presence of air (Exp. 2). CONCLUSION: TMR silage can resist aerobic deterioration provided that a sufficient ensiling period has elapsed. Silages stored for only a few weeks may be susceptible to deterioration when air is infiltrated or where fewer ingredients are used in the TMR mixture. Copyright © 2007 Society of Chemical Industry 相似文献
108.
Influence of the introduction of flexible alkyl chains on the thermal behavior and mechanical properties of mesogenic epoxy thermosets 下载免费PDF全文
A mesogenic epoxy resin (DGETAM) was cured with a series of curing agents having different lengths of long alkyl chain (nBAB, n = 4, 8, 12). Properties of the curings were compared with those of the DGEBA cured with the same curing agents revealing the achievement of a balance between certain levels of thermal properties and excellent mechanical properties. Moreover, some curing systems were prepared with twin mesogenic type epoxy resins (DGEnMA, n = 4, 6, 8, 10, 12) having different lengths of alkyl chain as a flexible spacer and the same curing agents (n′BABs). Combinations of the same concentrations of chemical structures in the basic units of the network structure were applied, and the thermal and mechanical properties of their curing systems were investigated. The fracture energy of each system increased considerably with the increase of the alkyl chain length that adjoins the two mesogenic groups in the epoxy resins. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 44244. 相似文献
109.
Nonsalt 1‐(arylmethyloxy)pyrene photoinitiators capable of initiating cationic polymerization 下载免费PDF全文
Analysis of photoproducts derived from 1‐(methoxynaphthalen‐1‐ylmethyloxy)pyrene initiators and polymer end groups demonstrated that methoxynaphthalen‐1‐ylmethyl carbocation is involved in the initiation steps for both styrene (St) and cyclohexene oxide (CHO) polymerization. Charge transfer from the pyrenyloxy oxygen atom to the methoxynaphthalen‐1‐ylmethyl chromophore in the singlet excited state is assumed to be responsible for the efficient generation of the carbocation species, which also initiates the copolymerization of St and CHO. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40510. 相似文献
110.
Sasao T Itoh N Takano H Watanabe S Wei G Tsukamoto T Kuzumaki N Takimoto M 《Reproduction (Cambridge, England)》2004,128(6):709-716
We have previously identified and cloned a human gene, D40, that is preferentially expressed in testis among normal organs, while it is widely expressed in various human tumor cell lines and primary tumors derived from different organs. In this report, we have examined the expression and localization of this protein in human testis with an antibody specific to D40 protein. In Western analyses, the anti-D40 antibody recognized a major band with a molecular mass of 300 kDa and a minor band of 250 kDa. These bands were not observed in the testis lysates from patients with Sertoli-cell-only syndrome and with Kleinfelter syndrome, who lack germ cells of the testis, indicating that D40 protein is expressed in the germ cells of normal testis. Immunohistochemical studies have revealed that D40 protein is highly expressed in spermatocytes and in the pre-acrosome of round spermatids. In the acrosome, D40 protein expression is observed not inside but outside the acrosome membrane. This is consistent with the finding that the amino-acid sequence at the amino terminal of the D40 protein lacks a hydrophobic signal peptide that is required for proteins to translocate to the membrane. Expression of D40 protein is observed in the acrosome of ejaculated spermatozoa as well, although the level is low compared with that in the pre-acrosome of spermatids. These results suggest that D40 protein plays important roles in spermatogenesis, especially in the formation and maintenance of the acrosome. 相似文献