101 research outputs found
好アルカリ性Bacillus A-007株のK^+ : 促進ATPaseについて
1.好アルカリ性Bacillus A-007株の生育にとってK^+は必須であった.2.K^+-濃度を制限した培地(1.5mMK^+)で生育させた細胞の膜画分に, K^+により促進されるATPase活性が認められた.3.K^+促進ATPaseは, 動力学的特性及びウワバイン, NaN_3, PCMBに対する感受件において, 同菌株のH^+-ATPaseと明らかに異なっていた.1. K^+ was essential for the growth of an alkalophilic Bacillus A-007. 2. Membrane fraction, which was prepared from the cells grown in K^+ -limited medium (1.5mM K^+), showed K^+ -stimulated ATPase activity. 3. The K^+ -stimulated ATPase was clearly different from H^+ -ATPase on kinetical profile and ouabain-, NaN_3- and PCMB-sensvtivity
Kinetics-Driven Crystal Facets Evolution at the Tip of Nanowires: A New Implementation of the Ostwald-Lussac Law
Nanocrystal facets
evolution is critical for designing nanomaterial
morphology and controlling their properties. In this work, we report
a unique high-energy crystal facets evolution phenomenon at the tips
of wurtzite zinc oxide nanowires (NWs). As the zinc vapor supersaturation
decreased at the NW deposition region, the NW tip facets evolved from
the (0001) surface to the {101̅3} surface and subsequently to
the {112̅2} surface and eventually back to the flat (0001) surface.
A series of NW tip morphology was observed in accordance to the different
combinations of exposed facets. Exposure of the high-energy facets
was attributed to the fluctuation of the energy barriers for the formation
of different crystal facets during the layer-by-layer growth of the
NW tip. The energy barrier differences between these crystal facets
were quantified from the surface area ratios as a function of supersaturation.
On the basis of the experimental observation and kinetics analysis,
we argue that at appropriate deposition conditions exposure of the
crystal facets at NW growth front is not merely determined by the
surface energy. Instead, the NW may choose to expose the facets with
minimal formation energy barrier, which can be determined by the Ehrlich–Schwoebel
barrier variation. This empirical law for the NW tip facet formation
was in analogy to the Ostwald–Lussac law of phase transformation,
which brings a new insight toward nanostructure design and controlled
synthesis
Structural Diversity and Properties of M(II) Coordination Compounds Constructed by 3‑Hydrazino-4-amino-1,2,4-triazole Dihydrochloride as Starting Material
Twelve metal coordination compounds
with two triazole derivatives, namely, {[Mn(HATr)<sub>2</sub>](ClO<sub>4</sub>)<sub>2</sub>}<sub><i>n</i></sub> (<b>1</b>), [Mn(HATr)<sub>3</sub>]Cl(ClO<sub>4</sub>) (<b>2</b>), [Co<sub>3</sub>(ATr)<sub>6</sub>(H<sub>2</sub>O)<sub>6</sub>](ClO<sub>4</sub>)<sub>6</sub>·4.5H<sub>2</sub>O (<b>3</b>), [Co(HATr)<sub>3</sub>]Cl(ClO<sub>4</sub>) (<b>4</b>), [Co<sub>2</sub>Cl<sub>2</sub>(HATr)<sub>2</sub>(H<sub>2</sub>O)<sub>2</sub>(CH<sub>3</sub>OH)<sub>2</sub>]Cl<sub>2</sub>·2H<sub>2</sub>O (<b>5</b>), [Ni<sub>3</sub>(ATr)<sub>6</sub>(H<sub>2</sub>O)<sub>6</sub>](ClO<sub>4</sub>)<sub>6</sub>·4.5H<sub>2</sub>O (<b>6</b>), [Ni(HATr)<sub>3</sub>]Cl(ClO<sub>4</sub>) (<b>7</b>), [Ni<sub>2</sub>Cl<sub>2</sub>(HATr)<sub>2</sub>(H<sub>2</sub>O)<sub>4</sub>](ClO<sub>4</sub>)<sub>2</sub>·4H<sub>2</sub>O (<b>8</b>), [Ni<sub>2</sub>(HATr)<sub>2</sub>(H<sub>2</sub>O)<sub>6</sub>](ClO<sub>4</sub>)<sub>4</sub>·2H<sub>2</sub>O (<b>9</b>), {[Zn(HATr)<sub>2</sub>](ClO<sub>4</sub>)<sub>2</sub>}<sub><i>n</i></sub> (<b>10</b>), [Zn(HATr)<sub>3</sub>]Cl(ClO<sub>4</sub>) (<b>11</b>), and {[Cd<sub>4</sub>(HATr)<sub>8</sub>](CdCl<sub>4</sub>)Cl<sub>2</sub>(ClO<sub>4</sub>)<sub>4</sub>}<sub><i>n</i></sub> (<b>12</b>), when HATr = 3-hydrazino-4-amino-1,2,4-triazole
and ATr = 4-amino-1,2,4-triazole, were prepared under diverse conditions
and structurally characterized. Compounds <b>1</b>, <b>10</b> and <b>12</b> exhibit one-dimensional zigzag chain structures; <b>2</b>, <b>4</b>, <b>7</b>, and <b>11</b> possess
mononuclear structures; <b>3</b> and <b>6</b> display
trinuclear structures, while <b>5</b>, <b>8</b>, and <b>9</b> feature binuclear structures. Hydrogen bonds link these
compounds into three-dimensional structures. The thermal stability
and energetic properties also were determined
Evolution of Hollow TiO<sub>2</sub> Nanostructures via the Kirkendall Effect Driven by Cation Exchange with Enhanced Photoelectrochemical Performance
Hollow nanostructures are promising
building blocks for electrode
scaffolds and catalyst carriers in energy-related systems. In this
paper, we report a discovery of hollow TiO<sub>2</sub> nanostructure
evolution in a vapor–solid deposition system. By introducing
TiCl<sub>4</sub> vapor pulses to ZnO nanowire templates, we obtained
TiO<sub>2</sub> tubular nanostructures with well-preserved dimensions
and morphology. This process involved the cation exchange reaction
between TiCl<sub>4</sub> vapor and ZnO solid and the diffusion of
reactants and products in their vapor or solid phases, which was likely
a manifestation of the Kirkendall effect. The characteristic morphologies
and the evolution phenomena of the hollow nanostructures from this
vapor–solid system were in a good agreement with the Kirkendall
effect discovered in solution systems. Complex hollow TiO<sub>2</sub> nanostructures were successfully acquired by replicating various
ZnO nanomorphologies, suggesting that this unique cation exchange
process could also be a versatile tool for nanostructure replication
in vapor–solid growth systems. The evolution of TiO<sub>2</sub> nanotubes from ZnO NW scaffolds was seamlessly integrated with TiO<sub>2</sub> NR branch growth and thus realized a pure TiO<sub>2</sub>-phased 3D NW architecture. Because of the significantly enlarged
surface area and the trace amount of Zn left in the TiO<sub>2</sub> crystals, such 3D TiO<sub>2</sub> nanoforests demonstrated enhanced
photoelectrochemical performance particularly under AM (air mass)
1.5G illumination, offering a new route for hierarchical functional
nanomaterial assembly and application
A Novel Process for the Key Intermediate of Fluoroquinolones
A Novel Process for the Key Intermediate of Fluoroquinolone
Plot illustrates findings from meta-analysis of the association between HIF-1α overexpression and tumor vascular invasion in 7 trials.
<p>Each study was shown by the name of the first author and the OR with 95% CIs. The summary OR and 95% CIs were also shown (according to the random effect estimations).</p
Flow diagram indicating the process of selecting articles for meta-analysis.
<p>Flow diagram indicating the process of selecting articles for meta-analysis.</p
Plot illustrates findings from meta-analysis of the association between HIF-1α overexpression and overall survival (OS) in 7 trials.
<p>Each study was shown by the name of the first author and the HR with 95% CIs. The summary HR and 95% CIs were also shown (according to the fixed effect estimations).</p
Plot illustrates findings from meta-analysis of the association between HIF-1α overexpression and disease free survival (DFS) in 7 trials.
<p>Each study was shown by the name of the first author and the HR with 95% CIs. The summary HR and 95% CIs were also shown (according to the fixed effect estimations).</p
Performance for all the 63 groups of measurements in cross-validation.<sup>*</sup>
*<p>Six measurements are represented as following: 1/mono-nucleotide frequencies, 2/di-nucleotide frequencies, 3/mono-codon composition, 4/di-codon composition, 5/mono-amino acid usages, 6/di-amino acid usages.</p>a<p>The boldface letter indicates the group with highest accuracy among the 63 combinations.</p
- …