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21.
Organosilane surfactant-directed synthesis of mesoporous aluminophosphates constructed with crystalline microporous frameworks 总被引:1,自引:0,他引:1
A direct hydrothermal assembly process was developed to synthesize mesoporous aluminophosphates that are constructed with crystalline microporous frameworks, by the addition of organosilane surfactants into the conventional synthesis composition for crystalline microporous aluminophosphates. 相似文献
22.
Choi JH Oh IG Ryoo KS Lim WT Park YC Habibi MH 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2006,65(5):1138-1143
The structure of [CrF(2)([15]aneN(4))]ClO(4).H(2)O ([15]aneN(4)=1,4,8,12-tetraazacyclopentadecane) has been determined by a single-crystal X-ray diffraction study at 173 K. The complex crystallizes in the space group P1- of the triclinic system with two mononuclear formula units in a cell of dimensions a=9.6117(7) A, b=10.2882(7) A, c=11.0001(7) A and alpha=99.7570(10) degrees, beta=105.6080(10) degrees and gamma=113.7130(10) degrees. The complex cation unit has its central Cr atom in an octahedral coordination with four nitrogen atoms and two fluorine atoms in a trans position. Three six-membered and one five-membered chelate rings of the [15]aneN(4) ligand are in a chair-twist(skew)-chair-gauche conformation sequence. The gauche five-membered ring is disordered with the twist six-membered ring opposite. The four H atoms in the chiral N atoms have the trans-II (CTCg) type configuration. The mean Cr-N and Cr-F bonds are 2.095(2) and 1.8752(13) A, respectively. The IR and visible spectral properties are consistent with the result of X-ray crystallography. The resolved band maxima of the electronic d-d spectrum are fitted with secular determinant for quartet state energy of d(3) configuration in tetragonal field including configurational but neglecting spin-orbit coupling. It is confirmed that the fluoride has strong sigma- and pi-donor properties toward the chromium(III) ion and the nitrogen atoms of the [15]aneN(4) ligand also have a strong sigma-donor character. 相似文献
23.
24.
Seunghoon Lee Jaeyoung Kim Hyunwoo Yang Emiliano Corts Seungwoo Kang Sang Woo Han 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(44):16037-16041
Designing plasmonic hollow colloids with small interior nanogaps would allow structural properties to be exploited that are normally linked to an ensemble of particles but within a single nanoparticle. Now, a synthetic approach for constructing a new class of frame nanostructures is presented. Fine control over the galvanic replacement reaction of Ag nanoprisms with Au precursors gave unprecedented Au particle‐in‐a‐frame nanostructures with well‐defined sub‐2 nm interior nanogaps. The prepared nanostructures exhibited superior performance in applications, such as plasmonic sensing and surface‐enhanced Raman scattering, over their solid nanostructure and nanoframe counterparts. This highlights the benefit of their interior hot spots, which can highly promote and maximize the electric field confinement within a single nanostructure. 相似文献
25.
Racemic-metal complexes were used to determine identity, enantiomeric excess, and concentration of chiral diamines using metal-to-ligand charge transfer bands in circular dichroism spectroscopy. It takes under just 2 min per sample to determine [G]t and %R with tolerable errors (19% and 4%, respectively). The simplicity of the achiral receptors employed confers to this technique great potential for high-throughput screening. 相似文献
26.
27.
Lee WG Bang H Yun H Lee J Park J Kim JK Chung S Cho K Chung C Han DC Chang JK 《Lab on a chip》2007,7(4):516-519
This paper presents a novel method for an on-chip erythrocyte deformability test under optical pressure, especially to enhance the level of sensitivity with respect to the detection of cancerous diseases. To demonstrate the performance and sensitivity of the combined method, we introduce the concept of transit velocity, a modified elongation index, and shape recovery time of individual erythrocytes in a strictly confined region (2 microm deep, 4 microm wide, and 100 microm long). Finally, we investigate a synergy or convergence effect due to the combination of these parameters for in situ detection of cancerous diseases under optical pressure. 相似文献
28.
Teng Zhang Hyunwoo Yuk Shaoting Lin German A. Parada Xuanhe Zhao 《Acta Mechanica Sinica》2017,33(3):543-554
As polymer networks infiltrated with water, hydro-gels are major constituents of animal and plant bodies and have diverse engineering applications. While natural hydro-gels can robustly adhere to other biological materials, such as bonding of tendons and cartilage on bones and adhe-sive plaques of mussels, it is challenging to achieve such tough adhesions between synthetic hydrogels and engineer-ing materials. Recent experiments show that chemically anchoring long-chain polymer networks of tough synthetic hydrogels on solid surfaces create adhesions tougher than their natural counterparts, but the underlying mechanism has not been well understood. It is also challenging to tune sys-tematically the adhesion of hydrogels on solids. Here, we provide a quantitative understanding of the mechanism for tough adhesions of hydrogels on solid materials via a com-bination of experiments, theory, and numerical simulations. Using a coupled cohesive-zone and Mullins-effect model val-idated by experiments, we reveal the interplays of intrinsic work of adhesion, interfacial strength, and energy dissipation in bulk hydrogels in order to achieve tough adhesions. We fur-ther show that hydrogel adhesion can be systematically tuned by tailoring the hydrogel geometry and silanization time of solid substrates, corresponding to the control of energy dis-sipation zone and intrinsic work of adhesion, respectively. The current work further provides a theoretical foundation for rational design of future biocompatible and underwater adhesives. 相似文献
29.
The generation of reactive oxygen species is thought to cause extensive oxidative damage to various biomolecules such as DNA,
RNA, and protein. In this study, the preventive, suppressive, and protective effects of in vitro supplementation with electrolyzed-reduced
water on H2O2-induced DNA damage in human lymphocytes were examined using a comet assay. Pretreatment, cotreatment, and posttreatment with
electrolyzed-reduced water enhanced human lymphocyte resistance to the DNA strand breaks induced by H2O2 in vitro. Moreover, electrolyzed-reduced water was much more effective than diethylpyrocarbonate-treated water in preventing
total RNA degradation at 4 and 25°C. In addition, electrolyzed-reduced water completely prevented the oxidative cleavage of
horseradish peroxidase, as determined using sodium dodecyl sulfate-polyacrylamide gels. Enhancement of the antioxidant activity
of ascorbic acid dissolved in electrolyzed-reduced water was about threefold that of ascorbic acid dissolved in nonelectrolyzed
deionized water, as measured by a xanthine-xanthine oxidase superoxide scavenging assay system, suggesting an inhibitory effect
of electrolyzed-reduced water on the oxidation of ascorbic acid. 相似文献
30.
Ji Yeon Choi Ji-Eun Bae Joon Bum Kim Doo Sin Jo Na Yeon Park Yong Hwan Kim Ha Jung Lee Seong Hyun Kim So Hyun Kim Hong Bae Jeon Hye-Won Na Hyungjung Choi Hong-Yeoul Ryu Zae Young Ryoo Hyun-Shik Lee Dong-Hyung Cho 《Molecules (Basel, Switzerland)》2021,26(17)
Primary cilia mediate the interactions between cells and external stresses. Thus, dysregulation of primary cilia is implicated in various ciliopathies, e.g., degeneration of the retina caused by dysregulation of the photoreceptor primary cilium. Particulate matter (PM) can cause epithelium injury and endothelial dysfunction by increasing oxidative stress and inflammatory responses. Previously, we showed that PM disrupts the formation of primary cilia in retinal pigment epithelium (RPE) cells. In the present study, we identified 2-isopropylmalic acid (2-IPMA) as a novel inducer of primary ciliogenesis from a metabolite library screening. Both ciliated cells and primary cilium length were increased in 2-IPMA-treated RPE cells. Notably, 2-IPMA strongly promoted primary ciliogenesis and restored PM2.5-induced dysgenesis of primary cilia in RPE cells. Both excessive reactive oxygen species (ROS) generation and activation of a stress kinase, JNK, by PM2.5 were reduced by 2-IPMA. Moreover, 2-IPMA inhibited proinflammatory cytokine production, i.e., IL-6 and TNF-α, induced by PM2.5 in RPE cells. Taken together, our data suggest that 2-IPMA ameliorates PM2.5-induced inflammation by promoting primary ciliogenesis in RPE cells. 相似文献