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41.
Wakui C Akiyama H Watanabe T Fitch MM Uchikawa S Ki M Takahashi K Chiba R Fujii A Hino A Maitani T 《Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan》2004,45(1):19-24
A histochemical assay for detecting genetically modified (GM) papaya (derived from Line 55-1) is described. GM papaya, currently undergoing a safety assessment in Japan, was developed using a construct that included a beta-glucuronidase (GUS) reporter gene linked to a virus coat protein (CP) gene. Histochemical assay was used to visualize the blue GUS reaction product from transgenic seed embryos. Twelve embryos per fruit were extracted from the papaya seeds using a surgical knife. The embryos were incubated with the substrate 5-bromo-4-chloro-3-indolyl-beta-D-glucuronide (X-Gluc) in a 96-well microtiter plate for 10-15 hours at 37 degrees C. Seventy-five percent of GM papaya embryos should turn blue theoretically. The histochemical assay results were completely consistent with those from a qualitative polymerase chain reaction (PCR) method developed by this laboratory. Furthermore, the method was validated in a five-laboratory study. The method for detection of GM papaya is rapid and simple, and does not require use of specialized equipment. 相似文献
42.
Tomoyuki Ishikawa Kenji Takasa Takehiko Yamashita Kohshiroh Mizuno Kunihiko Takeda 《应用聚合物科学杂志》2007,104(1):156-161
The thermal behaviors and the flame‐retardancy of styrene–ethylene–butadiene–styrene–block copolymer containing various additives were studied. The combustion was measured by the Underwriter laboratory (UL) test and cone calorimeter test and thermogravimetric analysis and program‐mass spectroscopy were applied to analyze the thermal behaviors. The blend with halogen additives showed the best result in the UL test. However, the blend with red‐phosphorous was the best in the cone calorimeter test. As the styrene sequence in the copolymer tended to degradate at a lower temperature, the major scission products spouted out from the polymer surface originated from polystyrene. The shorter the ignition times of the blends with red‐phosphorous were, the lower the peak heat release rates were. It was an interesting phenomenon because it suggested that the chemical structure of the residue changed to more stable polymers. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 156–161, 2007 相似文献
43.
Effect of viscosities of dispersed and continuous phases in microchannel oil-in-water emulsification
Koen van Dijke Isao Kobayashi Karin Schroën Kunihiko Uemura Mitsutoshi Nakajima Remko Boom 《Microfluidics and nanofluidics》2010,9(1):77-85
Although many aspects of microchannel emulsification have been covered in literature, one major uncharted area is the effect
of viscosity of both phases on droplet size in the stable droplet generation regime. It is expected that for droplet formation
to take place, the inflow of the continuous phase should be sufficiently fast compared to the outflow of the liquid that is
forming the droplet. The ratio of the viscosities was therefore varied by using a range of continuous and dispersed phases,
both experimentally and computationally. At high viscosity ratio (η
d/η
c), the droplet size is constant; the inflow of the continuous phase is fast compared to the outflow of the dispersed phase.
At lower ratios, the droplet diameter increases, until a viscosity ratio is reached at which droplet formation is no longer
possible (the minimal ratio). This was confirmed and elucidated through CFD simulations. The limiting value is shown to be
a function of the microchannel design, and this should be adapted to the viscosity of the two fluids that need to be emulsified. 相似文献
44.
45.
We propose a new function of the two-dimensional lens array that is composed of many gradient-index lenses. The array forms three-dimensional (3D) images. The characteristics of the 3D images depend on the length of the gradient-index lens. Especially, if the length of the lens is an odd-integer multiple of the half period of the optical path, 3D images are pseudoscopic with a reversed depth. The two lens arrays are positioned at a suitable distance, so that orthoscopic 3D images with the correct depth are formed in front of the lens array. 相似文献
46.
Given a set $\T$ of rooted, unordered trees,
where each $T_i \in \T$ is distinctly leaf-labeled by a set $\Lambda(T_i)$
and where the sets $\Lambda(T_i)$ may overlap,
the maximum agreement supertree problem~(MASP) is to construct a distinctly
leaf-labeled tree $Q$
with leaf set $\Lambda(Q) \subseteq $\cup$_{T_i \in \T} \Lambda(T_i)$
such that $|\Lambda(Q)|$ is maximized and for each $T_i \in \T$,
the topological restriction of $T_i$ to $\Lambda(Q)$ is isomorphic to
the topological restriction of $Q$ to $\Lambda(T_i)$.
Let $n = \left| $\cup$_{T_i \in \T} \Lambda(T_i)\right|$,
$k = |\T|$, and $D = \max_{T_i \in \T}\{\deg(T_i)\}$.
We first show that MASP with $k = 2$ can be solved
in $O(\sqrt{D} n \log (2n/D))$ time, which is $O(n \log n)$ when
$D = O(1)$ and $O(n^{1.5})$ when $D$ is unrestricted.
We then present an algorithm for MASP with $D = 2$ whose running time is polynomial if $k = O(1)$.
On the other hand, we prove that MASP is NP-hard for any fixed
$k \geq 3$ when $D$ is unrestricted,
and also NP-hard for any fixed $D \geq 2$ when $k$ is unrestricted even if
each input tree is required to contain at most three leaves.
Finally, we describe a polynomial-time $(n/\!\log n)$-approximation algorithm
for MASP. 相似文献
47.
Time-alternating method based on single-sideband holography with half-zone-plate processing for the enlargement of viewing zones 总被引:1,自引:0,他引:1
The single-sideband method of holography, as is well known, cuts off beams that come from conjugate images for holograms produced in the Fraunhofer region and from objects with no phase components. The single-sideband method with half-zone-plate processing is also effective in the Fresnel region for beams from an object that has phase components. However, this method restricts the viewing zone to a narrow range. We propose a method to improve this restriction by time-alternating switching of hologram patterns and a spatial filter set on the focal plane of a reconstruction lens. 相似文献
48.
In this paper, we proposed a method to predict the capacity of a heat exchanger by considering static pressure distributions of refrigerants. The thermal network method was modified by adding an equivalent heat generation term into a heat balance equation that was connected with calculated 1D static pressure distributions of refrigerants. An experiment was performed with a heat exchanger having two rows and two passes to verify the accuracy of the proposed method. The result showed the error of the predicted capacity to be less than 1% for an evaporator and less than 2% for a condenser. © 2002 Wiley Periodicals, Inc. Heat Trans Asian Res, 31(5): 376–390, 2002; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/htj.10039 相似文献
49.
T. Okano J. Tanabe M. Fukuda M. Tanaka 《Journal of the American Oil Chemists' Society》1992,69(1):44-46
The surface-active properties and emulsification ability of sodium α-sulfonated fatty acid esters, CmH2m+1CH-(SO3Na)COOCnH2n+1, were studied as a function of the hydrophobic alkyl chainlength in the fatty acid (m=8−16) and the alcohol (n=8−18). As
a result, it was discovered that sodium α-sulfonated fatty acid esters have a structural effect on the Krafft point different
from that of amphiphiles with short alkyl chains. Moreover, some of the α-sulfonated fatty acid esters have quite low interfacial
tensions, as well as non-foaming properties, which depend upon the total (m+n) number of carbon atoms in the alkyl chains. 相似文献
50.
The dimer and trimer obtained by the pyrolysis of poly(p-chlorostyrene) were 2,4-di(p-chlorophenyl)-1-butene and 2,4,6-tri(p-chlorophenyl)-1-hexene, respectively, while those obtained by the cationic oligomerization of p-chlorostyrene were trans-1,3-di(p-chlorophenyl)-1-butene and a diastereomeric pair of trans-1,3,5-tri-(p-chlorophenyl)-1-hexene. 相似文献