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991.
Summary A simple and sensitive method is presented for determination of styrene, toluene, ethylbenzene, isopropylbenzene andn-propylbenzene in human body fluids by capillary gas chromatography (GC) with cryogenic oven trapping. After heating a blood
or urine sample containing each compound andp-diethylbenzene (internal standard, IS) in a 7.0-mL vial at 60°C for 20 min, 5 mL of headspace vapor was drawn into a glass
syringe and injected into a GC. All vapor was introduced into an Rtx-Volatile middle bore capillary column in splitless mode
at oven temperature of 20°C to trap entire analytes, and the oven temperature then programmed to 280°C for GC measurements
by flame ionization detection. The present conditions gave sharp peaks of each compound and IS, and low background noises
for whole blood or urine samples. 相似文献
992.
通过410MeV 82Se轰击天然Ba靶引起的深部非弹反应布居产生了类弹和类靶余核的激发态,利用在束γ谱学方法测量了它们的退激γ.通过γ–γ符合测量估计了类弹、类靶余核激发态的产生截面,在多个类靶余核中观测到了新γ跃迁,并建立了136Ba的新能级纲图,说明利用深部非弹反应研究Z≈56,N≈80区高自旋态是有效、可行的. 相似文献
993.
O. Schließmann G. Bogatzki H. Pinsl E. Bischof G. Geuer W. M. Swenigorodskaja R. Weihrich W. Schwarz W. W. Stepin N. W. Musowskaja A. T. Tscherny E. Diepschlag L. G. Stadler I. M. Bessonow A. T. Sweschnikow T. W. Boretzkaja B. A. Ssossnowski R. Ishii A. G. Bogdantschenko S. N. Schkotowa O. Quadratund Vl. Vcělák S. Mischoinsniky 《Analytical and bioanalytical chemistry》1942,124(11-12):429-441
994.
Masatoshi Ohnishi Hirokazu Shikata Masaaki Sakakura Yasuhiko Shimotsuma Kiyotaka Miura Kazuyuki Hirao 《Applied Physics A: Materials Science & Processing》2010,98(1):123-127
Micro machining of a polyimide film with ultra-short pulsed laser was demonstrated. A through-hole with a diameter of less
than 10 μm could be produced by optimizing the pulse duration, repetition rate, and number of shots. Thermal damage around
the through-hole can be made negligibly small when the pulse duration was shorter than 140 fs. We also found that the minimum
shot number needed for the creation of a through-hole becomes smaller as the repetition rate of laser shot increases. On the
basis of the optimum irradiation condition, we demonstrated laser cutting of a polyimide film without thermal damage and copper
filling in through-holes with diameters of 9 μm by a plating process. 相似文献
995.
996.
The Ramanujan Journal - We explicitly compute the complex archimedean part of the Godement–Jacquet zeta integral. We give a pair of a Schwartz–Bruhat function and a matrix coefficient... 相似文献
997.
Mikihito Takenaka Shusuke Aburaya Satoshi Akasaka Hirokazu Hasegawa Nikos Hadjichristidis George Sakellariou Yasuhiko Tada Hiroshi Yoshida 《Journal of Polymer Science.Polymer Physics》2010,48(22):2297-2301
We have demonstrated directed self‐assembly of poly(styrene‐b‐dimethylsiloxiane) (PS‐b‐PDMS) down to sub‐10‐nm half‐pitch by using grating Si substrate coated with PDMS. The strong segregation between PS and PDMS enables us to direct the self‐assembly in wide grooves of the grating substrate up to 500 nm in width. This process can be applied to form various type of sub‐10‐nm stripe pattern along variety of grating shape. © 2010 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2010 相似文献
998.
Hoi Ling Seng Kong Wai Tan Mohd Jamil Maah Wee Tee Tan Hirokazu Hamada Makoto Chikira Chew Hee Ng 《Polyhedron》2009
A set of copper(II) complexes of glycine and methylated glycine derivatives, Cu(aa)2, consisting of C-dimethylglycine, l-alanine, N-dimethylglycine and sarcosine, was investigated for their DNA binding and nucleolytic properties by means of EPR and visible spectroscopy, and electrophoresis. They bind weakly to DNA with apparent binding constants in the range 1.8–2.9 × 103 M−1 with very similar orientation. No DNA cleavage is observed in the absence of exogenous agents. Copper(II) complexes of N-methylated derivatives bind to DNA more stereo-specifically and less strongly, and their oxidative DNA cleavage is less efficient than those of the corresponding C-methylated derivatives in the presence of hydrogen peroxide (H2O2) alone, or sodium ascorbate (NaHA) alone or tandem H2O2–NaHA. The oxidative DNA cleavage mechanism in the three systems involves a common copper(I) species. Neocuproine can inhibit DNA cleavage by these complexes. 相似文献
999.
ABSTRACTCurrent anvil designs and problems associated with various efforts to generate static high pressures beyond the limit of conventional diamond anvil cells (DACs) (~400?GPa) are reviewed. Pressures of up to 1?TPa have been reported by one research group using the double-stage DAC (ds-DAC) technique, but no other research group has successfully reproduced this high pressure result. Some research groups have used toroidal anvils, achieving pressures of >400?GPa. We have conducted numerous ds-DAC experiments and investigated the problems associated with such experiments. They include problems associated with various pressure scales in the multi-megabar region, difficulties in obtaining reliable X-ray diffraction patterns from micron-sized samples, and physical property measurements of tiny materials that may be harder than diamond. Each of these problems is discussed, following the summary of various experiments. 相似文献
1000.
Combined use of the method of sum of squares (SOS) and quantifier elimination (QE) is discussed with regard to the problem of nonlinear gain analysis for a class of dynamical systems. SOS, a numerical method, is used to search for the structure of a gain function quickly, and QE, a symbolic method, determines all gain functions in the structure to find the minimum gain function. QE can also be used for the infeasibility check of gain structures. A proposed analysis procedure for polynomial dynamical systems prevents unnecessary searching for a gain structure. Two illustrative examples show the effectiveness of the proposed gain analysis procedure. 相似文献