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241.
Sada K Inoue K Tanaka T Tanaka A Epergyes A Nagahama S Matsumoto A Miyata M 《Journal of the American Chemical Society》2004,126(6):1764-1771
A series of 1-naphthylmethylammonium n-alkanoates from acetate to triacontanoate produce isomorphic layered structures in the crystalline state. The interlayer distances, d-spacings, are proportional to the lengths of the alkyl chains. This is attributed to synergic intermolecular interactions; pi-pi and CH-pi interactions of the naphthalene rings between the cations, hydrophobic interactions of the alkyl chains, and two-dimensional hydrogen-bond networks between the primary ammonium cations and the carboxylate anions. Salts made from carboxylic acids wider than 5.5 A in the cross sections produce another columnar structure with a one-dimensional ladder-type hydrogen-bond network. Steric parameters of the acid components provide an explanation for the isomerism of the hydrogen-bond network. 相似文献
242.
Mikami K Yusa Y Hatano M Wakabayashi K Aikawa K 《Chemical communications (Cambridge, England)》2004,(1):98-99
A cationic rhodium(I) complex having a skewphos ligand is shown to be a highly enantioselective catalyst for asymmetric carbocyclization of 1,6-enynes with tri-substituted olefins to control quaternary stereogenic centers of spiro-rings. 相似文献
243.
Titanium tetraiodide promotes an aza-Reformatsky-type reaction of alpha-iodomethyl ketone O-alkyl oximes with carbonyl compounds to give beta-hydroxy ketone O-alkyl oximes in good to high yields. 相似文献
244.
V. Pravdova B. Walczak D. L. Massart S. Kawano K. Toyoda R. Tsenkova 《Analytica chimica acta》2001,450(1-2):131-141
A PLS model for prediction of somatic cell count (SCC) based on near-infrared (NIR) spectra of unhomogenized milk is presented in the study. Samples of raw milk were collected from cows in the early lactation period (from 7th to 29th day after parturition). The NIR spectra were measured in the region 400–1100 nm. As reference method a fluoro-opto-electronic method was applied. Different preprocessing methods were investigated. The robust version of PLS regression was applied to handle outliers present in the dataset and the uninformative variable elimination–partial least squares (UVE–PLS) method was used to eliminate uninformative variables. The final model is acceptable for prediction of SCC in raw milk. 相似文献
245.
Kazuki Arihara Fusao Kitamura Takeo Ohsaka Koichi Tokuda 《Journal of Electroanalytical Chemistry》2001,510(1-2)
The spectro-electrochemical behavior of carbonate and bicarbonate ions at the Au(111) electrode surface was studied using the infrared reflection absorption spectroscopy (IRAS). An absorption band caused by the adsorbed carbonate ions was observed in the wavenumber region of 1425–1511 cm−1 both in Na2CO3 and NaHCO3 solutions. It was concluded that the adsorbed carbonate ions co-ordinate with the electrode surface in the unidentate state with their symmetry axis normal to the substrate. This orientation is retained in the whole potential region where carbonate ions adsorb on the electrode surface in contrast to the behavior of the carbonate ions adsorbed on the Pt(111) electrode surface. 相似文献
246.
A. Toyoda K. Ishida K. Shimomura Y. Matsuda W. Higemoto S. N. Nakamura T. Matsuzaki K. Nagamine 《Hyperfine Interactions》2001,132(1-4):307-312
Recently, the applicability of Penning trap mass spectrometry has been extended to nuclides with a half-life of less than
one second. The mass of 33Ar (T
1/2=174 ms) was measured using the ISOLTRAP spectrometer with an accuracy of 4.2 keV. This measurement provided a stringent test
of the Isobaric Multiplet Mass Equation (IMME) at mass number A=33 and isospin T=3/2. The fast measurement cycle that shows the way to other measurements of very-short-lived nuclides is presented. Furthermore,
the results of the IMME test are displayed.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
247.
The three-dimensional vortical structure and the mixing mechanism of a circular water jet were investigated by a flow visualization technique. The jet was excited by axial and azimuthal perturbations to stabilize and enhance axisymmetric and streamwise vortices. A laser fluorescent dye and a laser light sheet were used to visualize the jet. The three-dimensional views of vortical structure were constructed by applying the Taylor hypothesis to the jet cross-sectional images. The views reveal the details of the complicated vortical structure. From the three-dimensional views, the areas of jet-boundary surface were calculated to discuss the jet mixing mechanism. The areas of the unmixed region were also discussed to evaluate the mixing rate on the inside of the jet. The result suggests that the enhancement of axisymmetric and streamwise vortices is very effective to increase mixing. 相似文献
248.
DPY19L3 has been identified as a C-mannosyltransferase for thrombospondin type-1 repeat domain-containing proteins. In this study, we focused on the role of DPY19L3 in the myogenic differentiation of C2C12 mouse myoblast cells. We carried out DPY19L3 gene depletion using the CRISPR/Cas9 system. The result showed that these DPY19L3-knockout cells could not be induced for differentiation. Moreover, the phosphorylation levels of MEK/ERK and p70S6K were suppressed in the DPY19L3-knockout cells compared with that of parent cells, suggesting that the protein(s) that is(are) DPY19L3-mediated C-mannosylated and regulate(s) MEK/ERK or p70S6K signaling is(are) required for the differentiation. 相似文献
249.
Nagasawa Kazuki Yoshii Junki Yamamoto Shoji Arai Wataru Kaneko Satoshi Hirai Keita Tsumura Norimichi 《Optical Review》2021,28(4):449-461
Optical Review - We propose a layout estimation method for multi-layered ink using a measurement of the line spread function (LSF) and machine learning. The three-dimensional printing market for... 相似文献
250.
Dr. Satoshi Yamaguchi Kazuki Chujo Noriyuki Ohashi Dr. Kosuke Minamihata Prof. Dr. Teruyuki Nagamune 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(12):e202103941
There is growing demand for the precise remote control of cellular functions in various fields. Herein, a method for caging mammalian cells by coating with photodegradable protein-polymer hybrid shells to photo-control their functions without genetic engineering is reported. A layer-by-layer assembly of photocleavable synthetic materials through biotin-streptavidin (SA) binding was employed for cell coating. The cell surfaces were first biotinylated with photocleavable biotinylated poly(ethylene glycol)(PEG)-lipid and then coated by repeatedly layering SA and micelles of the PEG-lipid and photocleavable biotinylated four-arm PEG. The cell extension and adhesion were suppressed with the shells and then triggered with the degradation of the shells by light exposure. Macrophage phagocytosis was also stopped by caging with the shells and restarted by light-guided uncaging. This study provides the first proof of principle that cellular functions can be remotely controlled by steric hinderance of cell surfaces with photodegradable materials. 相似文献