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61.
Aota A Takahashi S Mawatari K Tanaka Y Sugii Y Kitamori T 《Analytical sciences》2011,27(12):1173-1178
Highly efficient cell-free plasma separation from 200 μL of human whole blood was realized via axial migration of blood cells and cross-flow filtration in a microchip. Although various analyses of small volumes of blood have been reported, a large volume of blood is necessary for obtaining blood cells and plasma for the conventional plasma separation technique of centrifugation. A highly efficient plasma separation method using small volumes of blood without hemolysis is an important issue. We developed a plasma separation method based on a microchip with a filter, which utilizes the axial migration of blood cells observed in blood vessels. Clogging and hemolysis on the filter can be prevented by the axial migration of the blood cells. Using this method, 65% of the plasma from 200 μL of whole blood was successfully separated without hemolysis. When the plasma separation microchip interfaced with a micro-ELISA system was applied to C-reactive protein (CRP) analysis, the CRP concentration obtained by the microchip showed good correlation with that obtained by conventional centrifugation. Total analysis time, including plasma separation, was achieved in only 25 min. 相似文献
62.
Yukiko Enomoto-Rogers Hiroshi Kamitakahara Arata Yoshinaga Toshiyuki Takano 《Cellulose (London, England)》2011,18(4):1005-1014
Self-assembled cellulose-pyrene nanoparticles were prepared from amphiphilic cellulose derivatives carrying a single pyrene
group at the reducing-end, N-(1-pyrenebutyloyl)-β-cellulosylamine (CELL13Py and CELL30Py, the number average degrees of polymerization (DPn) of 13 and 30, respectively) and N-(15-(1-pyrenebutyloylamino)-pentadecanoyl)-β-cellulosylamine (CELL13C15Py and CELL30C15Py, DPn of 13 and 30, respectively). Transmission electron microscopy (TEM) observation revealed that CELL13C15Py and CELL30C15Py
formed self-assembled nanoparticles with the average diameters of 108.8 and 40.0 nm, respectively. The average radius of CELL30C15Py
nanoparticles (20.0 nm) agreed well with the molecular length of its cellulose chain (19.2 nm). CELL30C15Py nanoparticles
were expected to have monolayered structure, consisting of cellulose shell with radial orientation and hydrophobic core of
15-(1-pyrenebutyloylamino)-pentadecanoyl groups. The fluorescent spectrum of CELL30C15Py nanoparticles showed an excimer emission
due to dimerized pyrene groups, indicating that the pyrene groups at the reducing-end of cellulose are associating in the
particles. The balance of hydrophilic and hydrophobic parts of the cellulose derivatives controlled their self-assembled nanostructures.
X-ray diffraction measurements revealed that radially oriented cellulose chains of CELL30C15Py nanoparticles were mostly amorphous,
and at the same time exhibited weak reflection pattern of cellulose II, which is believed to have anti-parallel orientation. 相似文献
63.
64.
One-step preparation of manganese-, iron-, and aluminum-promoted sulfated zirconias for reaction of butane to isobutane 总被引:1,自引:0,他引:1
Highly active superacids of Mn-, Fe-, and Al-sulfated ZrO2's for the isomerization of butane to isobutane were obtained by exposing zirconia gel to aqueous solutions of 0.05 M MnSO4, 0.25 M FeSO4, and 0.5 M Al2(SO4)3 followed by calcining in air at 700, 600, and 675°C, respectively. The catalysts were much more active than the superacid
of sulfated zirconia, the temperature difference to show the same conversion (20%) between the catalysts and sulfated zirconia
being 85, 77, and 85°C for the Mn-, Fe-, and Al-catalysts, respectively.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
65.
Melt-crystallized poly(ethylene terephthalate) and etched oligomer lamellae from the same polymer have been annealed under vacuum at temperatures between 200 and 260°C and times between 3 and 48 hr. The annealed samples were analyzed through determination of viscosity-average molecular weight, x-ray low-angle spacing, density, heat of fusion, and variation of melting point with heating rate. In all cases it could be shown that the crystal lamellar surfaces remained chemically reactive. Chain folds and chain ends in the surface were converted by chemical reaction to tie molecules between different crystals or different locations on the same lamella. 相似文献
66.
67.
Strategies for Diagnosing and Alleviating Artifactual Attenuation Associated with Large Gradient Pulses in PGSE NMR Diffusion Measurements 总被引:2,自引:0,他引:2
William S. Price Kikuko Hayamizu Hiroyuki Ide Yoji Arata 《Journal of magnetic resonance (San Diego, Calif. : 1997)》1999,139(2):205-212
The generation of phase-based artifacts resulting from mismatch in the effective areas (i.e., the time integrals) of sequential gradient pulses is discussed in the context of large gradient pulsed-gradient spin-echo (PGSE) NMR diffusion measurements. Such effects result in artifactual attenuation and distortion in the spectra which, in the first instance, are similar to (and commonly mistaken for) the effects of eddy currents. Small degrees of mismatch cause "unphysical" concave downward curvature in PGSE attenuation plots of freely diffusing species. However, larger mismatches can result in artifactual diffraction peaks in the plots which could easily be confused for true restricted diffusion effects. Although "rectangular" gradient pulses are preferable from a theoretical viewpoint, we found that shaped gradient (e.g., half-sine) pulses, which due to their slower rise and fall times were more tractable for the current amplifier, were more sequentially reproducible. As well as generating fewer phase-based artifacts such shaped pulses also decrease the likelihood of vibration problems. 相似文献
68.
Kawabata Masako Motoishi Shoji Ohta Akio Motomura Arata Saeki Hideya Tsukada Kazuaki Hashimoto Shintaro Iwamoto Nobuyuki Nagai Yasuki Hashimoto Kazuyuki 《Journal of Radioanalytical and Nuclear Chemistry》2021,330(3):913-922
Journal of Radioanalytical and Nuclear Chemistry - Both 64Cu and 67Cu are promising radionuclides in nuclear medicine. Production yields of these radionuclides were quantified by irradiating... 相似文献
69.
70.
Yamamoto A 《Physical review letters》2011,107(3):031601
We perform a first lattice QCD simulation including a two-flavor dynamical fermion with a chiral chemical potential. Because the chiral chemical potential gives rise to no sign problem, we can exactly analyze a chirally imbalanced QCD matter by Monte Carlo simulation. By applying an external magnetic field to this system, we obtain a finite induced current along the magnetic field, which corresponds to the chiral magnetic effect. The obtained induced current is proportional to the magnetic field and to the chiral chemical potential, which is consistent with an analytical prediction. 相似文献