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111.
Anti-tauro 1 beta-hydroxycholic acid antisera were prepared by immunizing rabbits with N-(1 beta,3 alpha, 7 alpha, 12 alpha-tetrahydroxy-5 beta-cholan-24-oyl)-2- aminopropionic acid-bovine serum albumin (BSA) conjugate. The antisera raised had high affinity (1.25-1.46 x 10(9) M-1) and specificity for conjugated 1 beta-hydroxycholic acid; cross-reactivity for glyco 1 beta-hydroxycholic acid was 100% and that for the glycine and taurine conjugates of other 1 beta-hydroxylated bile acids ranged from 11.30 to 0.23%. Urinary concentrations of conjugated 1 beta-hydroxycholic acid were determined by radioimmunoassay in newborns, 0-20 d after birth, in amounts ranging from 0.29 to 18.51 micrograms/ml and in women in late pregnancy (less than 1.13 micrograms/ml), as well as in normal women (less than 0.12 microgram/ml). 相似文献
112.
113.
Back Cover: CH Activation Generates Period‐Shortening Molecules That Target Cryptochrome in the Mammalian Circadian Clock (Angew. Chem. Int. Ed. 24/2015) 下载免费PDF全文
Tsuyoshi Oshima Dr. Iori Yamanaka Dr. Anupriya Kumar Dr. Junichiro Yamaguchi Dr. Taeko Nishiwaki‐Ohkawa Kei Muto Rika Kawamura Dr. Tsuyoshi Hirota Prof. Dr. Kazuhiro Yagita Prof. Dr. Stephan Irle Prof. Dr. Steve A. Kay Prof. Dr. Takashi Yoshimura Prof. Dr. Kenichiro Itami 《Angewandte Chemie (International ed. in English)》2015,54(24):7200-7200
114.
115.
Dr. Aya Yoshimura Yuki Takamachi Prof. Dr. Li‐Biao Han Prof. Dr. Akiya Ogawa 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(40):13930-13933
An efficient metal‐free diboration of terminal alkynes is reported. In the presence of a catalytic amount of organosulfides under light, the addition of bis(pinacolato)diboron (B2pin2) to terminal alkynes takes place efficiently to produce the corresponding double borylation products in good yields. Mechanistic studies indicate that this metal‐free sulfide‐catalyzed diboration of alkynes likely occurs by generation of a boryl‐centered radical with the aid of light and a sulfide, since such a radical was detected in the reaction mixture by electron spin resonance (ESR) spectroscopy. The present form of catalysis (sulfide/light) is thought to be unprecedented and provides a new means of preparation for organoboranes without heavy metal contamination in the products, which is highly desired in the preparation of drugs and electronic materials. 相似文献
116.
Aya Yoshimura Akihiro Nomoto Mari Uchida Hiroki Kusano Tomokazu Saeki Akiya Ogawa 《Research on Chemical Intermediates》2017,43(6):3433-3443
The functionalization of polysilanes is an important subject in materials science because functionalized polysilanes are expected to exhibit potentially innovative properties. This research aims at the addition of a water-shedding property to polysilanes by introducing perfluoroalkyl groups into their skeleton. The photoinduced iodoperfluoroalkylation of various vinylsilanes takes place successfully upon irradiation with a xenon lamp: vinylmonosilanes undergo iodoperfluoroalkylation with perfluoroalkyl iodides (RfI) regioselectively, and the corresponding perfluoroalkylated silanes are obtained in moderate to high yields. Detailed optimization of the photoinduced iodoperfluoroalkylation has been investigated to apply this method to the functionalization of polysilanes. Polysilanes having vinyl groups can be synthesized by the reductive coupling of dichlorovinylsilanes with samarium diiodide (SmI2) and samarium metal (Sm) upon irradiation with visible light. The synthesized vinylpolysilanes and RfI (about 1.0 mM CHCl3 solution) are coated on a glass plate sequentially, and then the following photoirradiation with light of a wavelength over 300 nm successfully adds an excellent water-shedding property to the glass plate. 相似文献
117.
A method for the resolution of all stress components from the first invariant J1 measured by thermoelastic stress analyzer is described. This method may be used to determine, not only surface stress, but also internal stress and stress on the underside.The method is based on the following procedure:
- 1. (1) Pick an arbitrary domain Ω, within the structure, for which the stresses are required.
- 2. (2) Measure J1 on the surface of Ω.
- 3. (3) Determine the optimum traction along the boundary Γ, which is a part of Ω, by the least squares method such that the difference between the measured J1 and the calculated J1 is at a minimum. Either FEM or BEM may be used for this calculation.
118.
Response of an elastic Bingham fluid to oscillatory shear 总被引:1,自引:0,他引:1
The response of an elastic Bingham fluid to oscillatory strain has been modeled and compared with experiments on an oil-in-water emulsion. The newly developed model includes elastic solid deformation below the yield stress (or strain), and Newtonian flow above the yield stress. In sinusoidal oscillatory deformations at low strain amplitudes the stress response is sinusoidal and in phase with the strain. At large strain amplitudes, above the yield stress, the stress response is non-linear and is out of phase with strain because of the storage and release of elastic recoverable strain. In oscillatory deformation between parallel disks the non-uniform strain in the radial direction causes the location of the yield surface to move in-and-out during each oscillation. The radial location of the yield surface is calculated and the resulting torque on the stationary disk is determined. Torque waveforms are calculated for various strains and frequencies and compared to experiments on a model oil-in-water emulsion. Model parameters are evaluated independently: the elastic modulus of the emulsion is determined from data at low strains, the yield strain is determined from the phase shift between torque and strain, and the Bingham viscosity is determined from the frequency dependence of the torque at high strains. Using these parameters the torque waveforms are predicted quantitatively for all strains and frequencies. In accord with the model predictions the phase shift is found to depend on strain but to be independent of frequency.Notation
A
plate strain amplitude (parallel plates)
-
A
R
plate strain amplitude at disk edge (parallel disks)
-
G
elastic modulus
-
m
torque (parallel disks)
-
M
normalized torque (parallel disks) = 2m/R
30
-
N
ratio of viscous to elastic stresses (parallel plates) =µ A/
0 ratio of viscous to elastic stresses (parallel disks) =µ A
R/0
-
r
normalized radial position (parallel disks) =r/R
-
r
radial position (parallel disks)
-
R
disk radius (parallel disks)
-
t
normalized time = t — /2
-
t
time
-
E
elastic strain
-
P
plate strain (displacement of top plate or disk divided by distance between plates or disks)
-
PR
plate strain at disk edge (parallel disks)
-
0
yield strain
-
E
normalized elastic strain =
E/0
-
P
normalized plate strain =
P/0
-
PR
normalized plate strain at disk edge (parallel disks) =
PR/0
-
0
normalized plate strain amplitude (parallel plates) =A/
0 — normalized plate strain amplitude at disk edge (parallel disks) =A
R/0
-
phase shift between
P
andT (parallel plates) — phase shift between
PR
andM (parallel disks)
-
µ
Bingham viscosity
-
stress
-
0
yield stress
-
T
normalized stress =/
0
-
frequency 相似文献
119.
Mg isotope fractionation in biogenic carbonates of deep-sea coral, benthic foraminifera, and hermatypic coral 总被引:1,自引:0,他引:1
Yoshimura T Tanimizu M Inoue M Suzuki A Iwasaki N Kawahata H 《Analytical and bioanalytical chemistry》2011,401(9):2755-2769
High-precision Mg isotope measurements by multiple collector inductively coupled plasma mass spectrometry were applied for
determinations of magnesium isotopic fractionation of biogenic calcium carbonates from seawater with a rapid Mg purification
technique. The mean δ26Mg values of scleractinian corals, giant clam, benthic foraminifera, and calcite deep-sea corals were −0.87‰, −2.57‰, −2.34‰,
and −2.43‰, suggesting preferential precipitation of light Mg isotopes to produce carbonate skeleton in biomineralization.
Mg isotope fractionation in deep-sea coral, which has high Mg calcite skeleton, showed a clear temperature (T) dependence from 2.5 °C to 19.5 °C: 1,000 × ln(α) = −2.63 (±0.076) + 0.0138 (±0.0051) × T(R
2 = 0.82, p < 0.01). The δ26Mg values of large benthic foraminifera, which are also composed of a high-Mg calcite skeleton, can be plotted on the same
regression line as that for deep-sea coral. Since the precipitation rates of deep-sea coral and benthic foraminifera are several
orders of magnitude different, the results suggest that kinetic isotope fractionation may not be a major controlling factor
for high-Mg calcite. The Mg isotope fractionation factors and the slope of temperature dependence from deep-sea corals and
benthic foraminifera are similar to that for an inorganically precipitated calcite speleothem. Taking into account element
partitioning and the calcification rate of biogenic CaCO3, the similarity among inorganic minerals, deep-sea corals, and benthic foraminiferas may indicate a strong mineralogical
control on Mg isotope fractionation for high-Mg calcite. On the other hand, δ26Mg in hermatypic corals composed of aragonite has been comparable with previous data on biogenic aragonite of coral, sclerosponges,
and scaphopad, regardless of species differences of samples. 相似文献
120.
We consider energy estimates for second order homogeneous hyperbolic equations with time dependent coefficients. The property
of energy conservation, which holds in the case of constant coefficients, does not hold in general for variable coefficients;
in fact, the energy can be unbounded as t → ∞ in this case. The conditions to the coefficients for the generalized energy conservation (GEC), which is an equivalence
of the energy uniformly with respect to time, has been studied precisely for wave type equations, that is, only the propagation
speed is variable. However, it is not true that the same conditions to the coefficients conclude (GEC) for general homogeneous
hyperbolic equations. The main purpose of this paper is to give additional conditions to the coefficients which provide (GEC);
they will be called as C
k
-type Levi conditions due to the essentially same meaning of usual Levi condition for the well-posedness of weakly hyperbolic
equations. 相似文献