NUCLEAR INSTRUMENTS & METHODS IN PHYSICS RESEARCH SECTION B-BEAM INTERACTIONS WITH MATERIALS AND ATOMS
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2016
·
IF 1.389
Jinpeng Lv,Chundong Li
The discrepancy between sub-bandgap absorption in ZnO induced by thermal annealing and H + implantation is investigated in this study for the first time. Results indicate that nonreductive annealing-induced optical absorption is independent of annealing ambient, and can be assigned to V O , whereas the absorption centers caused by H + implantation and H 2 annealing are primarily associated with V O and ionized Zn i .
研究领域:
材料科学
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半导体物理
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光电子学
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Materials Horizons
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2026
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IF 11.4
Jiayu Wu,Pan Jiang,Xingxing Yang,Changcheng Bai,Ziyue Miao,Yixian Wang,Hang Zhang,Xiaolong Wang
Natural anisotropic tissues, such as tendons and cartilage, achieve remarkable mechanical properties and various biofunctions through oriented hierarchical structures. Inspired by organisms, we developed a synergistic molecular and structural engineering technique based on thermodynamically reversible reconfiguration of hydrogen bonds to achieve highperformance anisotropic supramolecular hydrogels by quenching pre-stretched polymer networks. Inherent multiple hydrogen bonds gradually dissociate under high-temperature processing to allow the well alignments of polymer chains by uniaxial pre-stretching. The oriented polymer chains are then fixed on-site by rapid quenching-mediated hydrogen bond reconstruction at low temperature (e.g., ice bath). This process merely relies on the inherent hydrogen bonds of polymer chains instead of traditional salting-out, metal ionic coordination and solvent effects. The optimal anisotropic hydrogel shows tensile strength of 19.4 ± 0.7 MPa, and toughness of 53.8 ± 5.2 MJ/m³ along to the pre-stretching direction, which are 2.6 and 1.7 times higher than that of unquenched isotropic hydrogels. This general strategy is applicable to different strong hydrogen bonding supramolecular hydrogel systems. Furthermore, we also fabricate anisotropic hydrogel fibers as damping materials. The general approach to prepare anisotropic supramolecular hydrogels promises great potential for various engineering applications, such as protective and cushioning materials, flexible optical and electronics, and mechanofunctional scaffolds.
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高影响因子
ACS Omega
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2023
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IF 4.1
Weijun Xie,Yue Zhang,Lei Xu,Dan Xie,Li Jiang,Yanmao Dong,Yan Yuan
In this study, upconversion nanoparticles (UCNPs) with a flower-like morphology were prepared using a urea coprecipitation method. A ternary photocatalyst was first prepared using a solvothermal method involving the use of titanium oxide (TiO2), hexagonal boron nitride (h-BN), and UCNPs (Y2O3, Yb3+, and Tm3+) as raw materials. The surface morphology, crystal structure, and functional groups of these materials were then characterized and analyzed through scanning electron microscopy, transmission electron microscopy, X-ray diffraction analysis, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, ultraviolet–visible spectrophotometry, and other techniques. Photocatalytic experiments were also conducted to investigate the effects of different catalyst types, raw material doping ratios, pH values, and catalyst quantities on the photocatalytic degradation of rhodamine B (RhB). The results indicated that doping with h-BN and UCNPs reduced the band gap width of RhB, increased its light absorption rate, and decreased the recombination rate of its photogenerated electrons and holes so that the photocatalytic degradation effect reached 100% within 2 h. After five experimental cycles, the 30% UC-BN-Ti photocatalyst remained highly durable and stable. To investigate the effects of different trapping agents on the degradation of RhB, benzoquinone, isopropanol, and ethylenediaminetetraacetic acid disodium salt were used as free-radical-capturing agents. The results indicated that •O2– was the primary active species in the degradation process. Finally, the pathway and mechanism of the degradation of RhB through ternary composite photocatalysis were identified.
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高影响因子
MOLECULES
·
2023
·Vol. 28
·期 8
·3574
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IF 4.6
Mengyu Li,Liyang Nan,Boxuan Zhang,Junjun Kong,Yufeng Wang,Miao Ba
By introducing thiourea and ether groups into MQ silicone resin polymer via free radical polymerization, a polyether-thiourea-siloxane (PTS) copolymer was synthesized. The characterization of the synthesized copolymer indicated the occurrence of H-bonding interactions and a narrow molecular weight polydispersity index. Antifouling coatings were produced by incorporating the synthesized copolymer and phenylmethylsilicone oil (PSO). The addition of a minute amount of copolymer enhanced the hydrophobicity of the coating by increasing its surface roughness. However, excessive addition of copolymer resulted in a significant deterioration of the coating surface smoothness. The copolymer improved the mechanical properties of the coating, but excessive addition decreased the crosslinking density and weakened the mechanical performance. With increasing copolymer addition, the leaching of PSO was significantly improved due to the change in the storage form of PSO in the coating caused by the copolymer. Based on the H-bonding interaction of the copolymer, the adhesion strength between the coating and the substrate was significantly improved. However, excessive addition of copolymer did not infinitely enhance the adhesion strength. The antifouling performance demonstrated that an appropriate amount of copolymer could obtain adequate PSO leaching efficiency, thereby effectively enhancing the antifouling performance of the coating. In this study, the prepared coating P12(12 g of PTS in 100 g of PDMS) showed the most effective antifouling performance.Keywords:marine antifouling;copolymer;H-bonding interaction;leaching;fouling release
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高影响因子
COLLOIDS AND SURFACES B-BIOINTERFACES
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2017
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IF 3.887
Zhili Deng,Menghuan Tang,Li Zhao,Yijuan Long,Zuhuang Wen,Yuan Cheng,Huzhi Zheng
A novel targeting drug delivery system for cancer therapy based on H + -triggered bubble-generating nanosystems (BGNSs) was engineered. First, hollow mesoporous silica nanoparticles (HMSNs) were used to load doxorubicin (DOX). Then, the obtained drug-loaded HMSNs were treated with NaHCO 3 to prepare the BGNSs. The BGNSs were coated with polydopamine (pDA), and finally, folic acids (FA) were anchored on the nanosystems to obtain the desired nanoscale drug delivery system ( [email protected] ). [email protected] was effectively internalized by cancer cells through folate receptor-mediated endocytosis and generated CO 2 bubbles under the acidic environment of the lysosomes, thus enhancing lysosomal membrane permeability (LMP) to release caspase-3 into the cytoplasm, resulting in cancer cell death via an apoptosis-like pathway. Notably, we demonstrated that the [email protected] exhibited a significant simultaneous synergetic cytotoxicity against MCF-7 cells and remarkably overcame the multidrug resistance (MDR) of MCF-7/ADR cells. Moreover, compared to free DOX and a nanosystem without FA modification (BGNSs), the [email protected] induced relatively minor side effects in the MCF-10A cells. Therefore, the results showed that [email protected] , as a targeted drug delivery system, have a good probability of overcoming the MDR of tumor cells with minor side effects on normal cells.
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高影响因子
JOURNAL OF MATERIALS SCIENCE
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2022
·Vol. 57
·期 42
·19799-19816
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IF 4.682
Zhu Jishi,Li Xinshuo,Yang Rui,Wen Jin,Li Xiaoke
The widespread application of solar-thermal absorbers is currently hindered by their low absorption efficiency and high capital cost. Therefore, many initiatives, including direct absorption solar collectors (DASCs), are currently under way to improve the efficiency of the absorbers. In this regard, the application of TiN-modified h-BN nanosheets in DASCs is studied in this paper. Their superior solar absorptivity and thermal conductivity are based on the plasma plasmon effect of nanoparticles and the high thermal conductivity of h-BN nanosheets, respectively. In the experiment, five different concentrations (20, 40, 60, 80, 100 ppm) of TiN@h-BN composite nanofluids were prepared by a two-step method. The stability and optical properties of the nanofluids were analyzed. In addition, thermal loss and exergic efficiency of photothermal conversion system were analyzed and discussed. Combined with localized surface plasmon resonance (LSPR) of TiN nanoparticles and h-BN light reflection properties, the photothermal conversion of TiN@h-BN composite nanofluids was improved in DASCs. The 80 ppm nanofluid showed the best exergic efficiency, with an average exergic efficiency of 83%. Meanwhile, the photothermal conversion efficiency of 80 ppm TiN@h-BN composite nanofluid reaches the maximum 78%. This work provides new strategies for harnessing the full spectrum of solar energy and controlling the photothermal properties of nanofluids. Graphical Abstract Schematic diagram of photothermal conversion system of TiN@h-BN nanofluids.
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Biosensors-Basel
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2022
·Vol. 12
·期 3
·141
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IF 5.743
Yijian Huang,Ying Wang,Gaixia Xu,Xing Rao,Jiaxiong Zhang,Xun Wu,Changrui Liao,Yiping Wang
A compact surface plasmon resonance sensor based on an H-shaped optical fiber is proposed and demonstrated. The H-shaped optical fiber was fabricated experimentally by using hydrofluoric acid to controllably corrode the polarization-maintaining fiber. A satisfactory distance between the outer surface of the fiber and the core can be achieved, and then the surface plasmon resonance effect can be excited by coating a metal film of appropriate thickness on the surface of the fiber. This technology can realize the preparation of multiple samples at one time, compared to the traditional side-polishing technique. The H-shaped optical fiber obtained from corrosion exhibits a high surface quality and short lengths, down to only a few hundred microns. The effects of the proposed H-shaped optical fiber on spectral properties are induced by process parameters, including fiber remaining thickness, coating thickness and fiber length, and were investigated in detail. The prepared sensor was used for the specific detection of human IgG, and the minimum human IgG concentration that the sensor can distinguish is 3.4 μg/mL. Such a compact surface plasmon resonance fiber sensor has the advantages of an easy fabrication, good consistency and low cost, and is expected to be applied in the specific detection of biomarkers.Keywords:surface plasmon resonance;biosensor;polarization-maintaining fiber;chemical corrosion
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高影响因子
JOURNAL OF ORGANIC CHEMISTRY
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2021
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IF 4.354
Yan-Ling Song,Bei Li,Zhen-Biao Xie,Dan Wang,Hong-Mei Sun
Iron-catalyzed oxidative amination of benzylic C(sp3)–H bonds with anilines bearing electron-withdrawing groups (EWGs) or electron-donating groups (EDGs) is realized based on simple variations of N-substituents on imidazolium cations in novel ionic Fe(III) complexes. The structural modification of the imidazolium cation resulted in regulation of the redox potential and the catalytic performance of the iron metal center. Using DTBP as oxidant, [HItBu][FeBr4] showed the highest catalytic activity for anilines bearing EWGs, while [HIPym][FeBr4] was more efficient for EDG-substituted anilines. This work provides alternative access to benzylamines with the advantages of both a wide substrate scope and iron catalysis.
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PubMed
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
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2021
·Vol. 138
·期 47
·51411
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IF 3.125
Xing-Ya Liu,Rui-Yang Xie,Tao Chen,Lei He,Ting Wang,Wang Liao,Zhi-Guo Liu,Ming-Jun Chen
Due to the condensation reaction of hydroxylated melamine molecules is possible to take place in the whole pH range, especially in acidic water medium or at high temperature, losing its water solubility. In this work, freeze drying perfectly removes water at pretty low temperature, avoiding condensation reaction of hydroxylated melamine. Therefore, a hydroxylated melamine in solid form (MOH-S) was prepared. It can be not only dissolved in water after storing for 180 days but also well dispersed in waterborne polyurethane emulsion. The addition of hydroxylated melamine significantly improves the tensile strength of polyurethane films by 170%. After soaking the films in water for 24 h, the tensile strength of WPU/30%MOH-S film lost only 6%, but 34% loss for the neat. Fourier transform infrared spectroscopy peak fitting demonstrates that the H-bonding degree of N─H in WPU/30%MOH-S film is 20.72 that is much higher than 3.33 in neat WPU. This indicates that H-bonding cross-linked structure is formed between polyurethane chains and hydroxylated melamine molecules. This work provides an effective strategy for preparing stable hydroxylated melamine and enhancing the strength of polyurethane film.
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高影响因子
Asian Journal of Organic Chemistry
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2017
·Vol. 7
·期 1
·240-247
·
IF 2.788
Rui Yan,Zhong-Xia Wang
Graphical Oxidative coupling of allylic alcohols : [Cp*RhCl 2 ] 2 was demonstrated to catalyze the oxidative coupling of alkenylpyridines with allylic alcohols through alkenyl C−H activation in the presence of AgOTf and AgOAc to afford β-alkenyl ketones and aldehydes in moderate to good yields. [Cp*RhCl 2 ] 2 was demonstrated to catalyze the oxidative coupling of alkenylpyridines with allylic alcohols through alkenyl C−H activation in the presence of AgOTf and AgOAc to afford β-alkenyl ketones and aldehydes in moderate to good yields. Allylic alcohol, 1-aryl and 1-alkyl allylic alcohols can be coupled with various alkenylpyridines. The reaction occurred at the γ-position of allylic alcohols and the cis -β-position of the alkenylpyridines.
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CONSTRUCTION AND BUILDING MATERIALS
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2017
·
IF 3.169
Jinfeng Sun,Hu Shi,Binbin Qian,Zhiqiang Xu,Weifeng Li,Xiaodong Shen
This work investigates the influence of synthetic C-S-H/polycarboxylate(PCE) nanocomposites (CPNs) on the hydration and properties of hydrated cement pastes. HPEG-PCE copolymers exhibiting side chain length of 45 ethylene oxide (EO) units was utilized to synthesize CPNs by precipitating C-S-H from Na 2 SiO 3 and Ca(NO 3 ) 2 in the PCE solution. A Box-Behnken Design (BBD) for the Response Surface Methodology (RSM) was employed to statistically optimize the sizes of the resultant. The prepared CPNs were characterized by particle size distribution (PSD), X-ray diffraction (XRD), Fourier transform infrared spectra (FT-IR) and thermo gravimetric/derivative thermo gravimetric (TG/DTG) analyses. The influence of CPNs on the hydration properties of cement were assessed and discussed in terms of hydration kinetics, mechanical properties, phase composition and pore structure analysis. The experimental results showed that the optimum synthetic parameters, an experimental temperature of 30.1 °C, reactant flow velocity of 0.63 ml/min and initial volume of PCE solution of 28.5 ml, produced CPNs with a minimum size of 329.12 nm. It was demonstrated that PCE polymers were either grafted on the surface or partially intercalated in the interlayer regions of C-S-H, and their introduction also increased the distance between C-S-H interlayers. Cement hydration was significantly promoted as a result of an increased heat release, even at low CPNs content. The early compressive strength of the mortar significantly improved with increasing CPNs content due to the accelerated cement hydration of the CPNs: the 0.6 wt.% CPNs content improved the compressive strength by 18.97%. Moreover, the inclusion of CPNs is advantageous for pore modification: the total porosity decreased by 25.77% after 3 days. Finally, phase composition analysis confirmed that no new crystalline phase was produced upon CPNs addition.
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CANADIAN JOURNAL OF CHEMICAL ENGINEERING
·
2013
·Vol. 92
·期 5
·851-860
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IF 1.003
Zhenhua Pan,Qizhou Cai,Qiang Luo,Xinwei Li
The mechanism and kinetics of synergetic effect in TiO 2 /O 3 /UV process on H-acid degradation were investigated. The experimental results showed that H-acid removal rate of TiO 2 /O 3 /UV process was the highest among TiO 2 /UV, O 3 /UV and TiO 2 /O 3 /UV processes. The investigation of reactions with suitable active species scavengers confirmed that H-acid was mainly oxidised by ozone and holes on TiO 2 in the TiO 2 /O 3 /UV process. The recombination between holes and electrons in TiO 2 reduced in the presence of ozone, as indicated by fluorescence emission spectra. Moreover, the intermediates generated during H-acid oxidation in various processes were analysed by LC/MSD trap. It is proposed that H-acid was oxidised to polyhydroxy aromatics, benzene carboxylic acids and quinoids in the first step. Then, saturated aliphatics carboxylic acids were formed and mineralised to inorganic compounds through the Photo-Kolbe reaction. Finally, a kinetic study on TiO 2 /UV, O 3 /UV and TiO 2 /O 3 /UV processes was conducted and it was confirmed that both ozonation and photocatalytic activity were improved in TiO 2 /O 3 /UV process because of the synergetic effect.
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