International Journal of Applied Ceramic Technology
·
2021
·Vol. 18
·期 4
·1183-1191
·
IF 1.968
Sen Wang,Feng Liang,Saisai Li,Liang Tian,Shaowei Zhang,Quanli Jia,Shuai Chang,Sheng Yan,Haijun Zhang
Monophase α-Si 3 N 4 was prepared by a salt melt strategy using Si as a starting material. The results showed that molten salt enhanced the conversion of Si to monophase α-Si 3 N 4 , and some as-synthesized α-Si 3 N 4 nanoparticles had a hexagonal platelet morphology. The α-Si 3 N 4 hexagonal nanoplatelets had an average lateral dimension of about 170 nm and a thickness of about 5.2 nm. The nitridation of Si in molten salt was investigated by a thermal quenching method, and the silicon halide intermediate products were detected by X-ray photoelectron spectroscopy. Silicon halides possessing higher reactive activity facilitated the nitridation of Si and nucleation of α-Si 3 N 4 . Furthermore, the lattice mismatch between α-Si 3 N 4 and the salts was calculated, suggesting that the lateral growth of α-Si 3 N 4 nanoplatelets had been guided by the salt crystal structure. Based on the results, the relevant formation mechanism of α-Si 3 N 4 nanoplatelets was proposed.
研究领域:
材料科学
·
纳米技术
✓ 已验证
DOI
高影响因子
MATERIALS CHEMISTRY AND PHYSICS
·
2021
·
IF 4.094
Xiao Guo,Haibo Wang,Rui Tian,Haojiang Yin,Yunfeng Qiu,Feng Wang
Hydrophobic α-Al 2 O 3 ceramic membrane (HCM) offers excellent mechanical properties , corrosion resistance , and high-temperature resistance. Application of HCM in the membrane distillation (MD) process could expand the application scope of MD equipment and greatly lengthen the replacement cycle of the membrane. Here a prediction model of the contact angle of HCM was constructed by physical-chemical combined modification method, orthogonal method, and stepwise linear regression method to optimize the preparation process of HCM. The surface morphology , contact angle, and surface functional groups of HCM were characterized. In this work, we polished the surface of the α-Al 2 O 3 ceramic membrane with 400 mesh sandpaper to copy the optimal morphology and found that the effect of grafting time on the contact angle of HCM could be abandoned. The optimal levels of drying temperature, drying time, and grafting solution concentration were 250 °C, 65.5 min, and 0.019 mol/L, respectively. The contact angle of HCM was 145.3° corresponding to the optimal preparation process. The significance of the prediction model of the contact angle of HCM was better than 0.05, and all of the prediction errors were less than 5%. This work has an important guiding value for exploiting the optimum hydrophobic property of HCM.
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
Nano Research
·
2024
·
IF 9.5
Zhao Yuan,Wang Qingshuang,Yin Dongming,Wang Xiaoli,Li Shouliang,Wang Chunli,Liang Long,Zhao Shaolei,Wang Limin,Cheng Yong
α-AlH 3 is regarded as one of the most promising hydrogen storage materials due to its high hydrogen storage capacity (10.1 wt.%, 148 kg·m −3 ). However, in practical applications, the associated hydrogen release temperature remains relatively high. To effectively address this issue, hollow structured Fe@C nanorods derived from Fe-MOF are introduced as highly efficient catalyst to optimize the dehydrogenation properties of α-AlH 3 . Comparatively, the initial hydrogen release temperature of α-AlH 3 + 3 wt.% Fe@C is reduced to 94.2 °C, which is significantly lower than that of pure α-AlH 3 (137.8 °C). At 100 and 120 °C, it exhibits hydrogen capacities of 5.38 wt.% and 7.47 wt.%, respectively, whereas pure α-AlH 3 only delivers hydrogen capacities of 0.24 wt.% and 5.94 wt.% under the same temperatures. The density functional theory (DFT) calculations further indicate that the existence of Fe@C catalyst can make the length of Al–H bond increase, which is more conducive to the release of hydrogen. The results show that the synergistic effect of Fe and porous carbon in Fe@C nanorods can improve the hydrogen desorption kinetics of α-AlH 3 , providing a good prospect for the application of α-AlH 3 in hydrogen storage fields.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2020
·
IF 3.83
Zunlan Hu,Jian Liu,Zhipeng Xie
Silicon nitride (Si 3 N 4 ) particles with different morphologies have been used in many fields. In this work, α-Si 3 N 4 whiskers and granular particles with high-phase purity were successfully tailored by the controllable crystallisation process of amorphous Si 3 N 4 powders under different N 2 pressure. Impressively, α-Si 3 N 4 whiskers were prepared by simply heat treating amorphous Si 3 N 4 powders at 1550 °C for 2 h under the low N 2 pressure of 0.2 MPa, whereas equiaxed α-Si 3 N 4 particles with uniform size of ~280 nm were obtained under an elevated N 2 pressure of 2.0 MPa. With the evaluated N 2 pressures and temperatures, large scale α-Si 3 N 4 whiskers or equiaxed α-Si 3 N 4 particles could be produced. The growth mechanisms of the α-Si 3 N 4 particles with distinct morphologies were rationally proposed, and these consist of two main growth processes. First, amorphous Si 3 N 4 powders decomposed into Si(g) and N 2 (g) under high-temperature treatment. Subsequently, N 2 (g) dominated the recombination of the evaporated chemical with the Si 3 N 4 molecule. The initial N 2 concentration, which plays a key role in tailoring the shape and size of products, was controlled by the N 2 pressure.
研究领域:
材料科学
·
无机化学
✓ 已验证
DOI
高影响因子
POLYHEDRON
·
2016
·
IF 2.108
Jingquan Sha,Xiya Yang,Longjiang Sun,Xiumei Zhang,Shuxian Li,Jisen Li,Ning Sheng
An assembly of cyclodextrin metal-organic frameworks (CD-MOFs) has aroused extensive research interests due to their excellent encapsulation capacity and biocompatibility. In this work, starting from the chiral building block α-cyclodextrin (α-CD), a novel α-CD-MOF compound with left-handed chiral helices, [Na(H 2 O)(C 36 H 60 O 30 )]·H 2 O (Na-α-CD-MOF), was synthesized through changing the diffusion solvent, and then structurally characterized. Single crystal X-ray diffraction analysis reveals that Na-α-CD-MOF exhibits a 3D left-handed helical chiral framework with large cavities (740 Å 3 ). The result of a drug adsorption assay shows Na-α-CD-MOF possesses a more efficient drug adsorption capacity than α-CD matrix, and the solubility of the drug adsorbed in Na-α-CD-MOF can be greatly enhanced. All the results, including the lower cytotoxicity, indicate that Na-α-CD-MOF is an excellent kind of renewable, environmental friendly and biocompatibility drug carrier material.
研究领域:
材料科学
·
药物化学
·
晶体学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
·
2018
·
IF 3.412
Huafang Ding,Xiaqing Wu,Junhui Pan,Xing Hu,Deming Gong,Guowen Zhang
Betulinic acid (BA), an important pentacyclic triterpene widely distributed in many foods, possesses high antidiabetic activity. In this study, BA was found to exhibit stronger inhibition of α-glucosidase than acarbose with an IC50 value of (1.06 ± 0.02) × 10–5 mol L–1 in a mixed-type manner. BA bound with α-glucosidase to form a BA−α-glucosidase complex, resulting in a more compact structure of the enzyme. The obtained concentrations and spectra profiles of the components resolved by the multivariate-curve resolution–alternating least-squares confirmed the formation of the BA−α-glucosidase complex. Molecular docking showed that BA tightly bound to the active cavity of α-glucosidase, which might hinder the entrance of the substrate leading to a decline in enzyme activity. The chemical modification of α-glucosidase verified the results of the computer simulation that the order of importance of the four amino acid residues in the binding process was His > Tyr > Lys > Arg.
研究领域:
药理学
·
生物化学
·
计算生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
FOOD CHEMISTRY
·
2018
·
IF 4.946
Li Zeng,Huafang Ding,Xing Hu,Guowen Zhang,Deming Gong
Inhibition of α-glucosidase and non-enzymatic glycation is considered as an effective approach to treat type 2 diabetes. Herein, multispectroscopic techniques and molecular docking analysis were used to investigate the inhibition of galangin on α-glucosidase and non-enzymatic glycation. Galangin showed a reversible inhibition on α-glucosidase activity in a mixed-type manner through a monophasic kinetic process, and induced the fluorescence quenching and conformational changes of α-glucosidase by forming α-glucosidase-galgangin complex. Molecular docking revealed that galangin primarily interacted with the amino acid residues within the active site of α-glucosidase, which may prevent the entrance of substrate resulting in a decrease in catalytic efficiency of α-glucosidase. Moreover, galangin moderately inhibited the formation of intermediates of non-enzymatic glycation, fructosamine and α-dicarbonyl compounds and strongly inhibited the formation of advanced glycation end products.
研究领域:
生物化学
·
药理学
·
糖尿病研究
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
·
2018
·Vol. 102
·期 6
·3307-3317
·
IF 2.956
Dandan Zhang,Jing Li,Jianye Liang,Heping Li,Youwei Yan
We report α-MoO 3 flowers as a highly effective organics adsorbent for the first time. With α-MoO 3 microfibers (MFs), α-MoO 3 flowers uniformly self-assemble on a carbon cloth, serving as a great organics scavenger. They not only provide a high specific surface area but also possess van der Waals force, both of which guarantee a high adsorption efficiency for multiple organics. Nearly 100% of Rhodamine B (RhB), methylene blue (MB), and crystal violet (CV) are rapidly adsorbed while flowing through the designed α-MoO 3 flower-based filtration device. Even after five recycling times, its high adsorption efficiency toward RhB remains unaffected. The adsorption capacity of α-MoO 3 flowers for RhB, MB, and CV reaches up to 4974, 6217, and 3886 mg/m 2 , respectively. Additionally, this novel adsorbent can adapt to a wide pH range, maintaining the excellent capacity of 4774 and 4473 mg/m 2 toward RhB at pH of 2.0 and 12.0. The α-MoO 3 flowers can also adsorb other organics, including MO, noroxin, and tetracycline hydrochloride. Moreover, the free-standing α-MoO 3 flowers on a carbon cloth realize the adsorptive filtration for organics removal, which not only require no conditions and no energy consumption but also avoid secondary pollution to the water as compared to the powdery adsorbents.
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
Environmental Science-Nano
·
2023
·
IF 7.3
Ruixue Wang,Kun Li,Narcisse Tsona Tchinda,Wenxing Wang,Lin Du
Ammonia (NH3), the most common alkaline gas in the atmosphere, participates in heterogeneous reactions on the surface of aerosols and produces ammonium (NH4+). While most previous studies have focused on the effect of NH3 on the heterogeneous reactions of other gases on mineral dust aerosols, little research has been done on the heterogeneous reactions of NH3 influenced by acidic gases. Here, the effects of sulfur dioxide (SO2), formic acid, acetic acid and acrylic acid on the heterogeneous reaction of NH3 on the surface of nano α-Fe2O3 particles were investigated. We found that NH3 can promote the dissolution of α-Fe2O3 through NH3–Fe complexation and be oxidized to NO3−, while the addition of acidic gas inhibits the NH3–Fe complex formation and converts it into physical adsorption. SO2 promoted the conversion of NH3 to NH4+, while weakly inhibiting the oxidation of NH3 to NO3− by competing for oxidation sites under light conditions. Organic acids, on the other hand, inhibited the heterogeneous conversion of NH3, and strongly competed for oxidation sites under light conditions, significantly reducing NO3− production. This study reveals the various influences of acidic gases on NH3 heterogeneous reactions on α-Fe2O3 particles, which helps to improve the understanding of atmospheric processes involving NH3, acidic gases, and mineral dust aerosols.
研究领域:
大气化学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
PLANTA MEDICA
·
2013
·
IF 2.348
Cui-Ting Luo,Huan-huan Zheng,Shuang-Shuang Mao,Mao-xun Yang,Cheng Luo,Heru Chen
Two new xanthones, 1,8-dihydroxy-3-methoxyxanthone 7-O-[α-L-rhamnopyranosyl(1 → 2)-β-D-glucopyranoside] (1) and 1,8- dihydroxy-3-methoxyxanthone 7-O-[α-L-rhamnopyranosyl(1 → 3)-α-L-rhamno-pyranosyl (1 → 2)-β-D-xylopyranoside] (2), together with 26 known xanthones (3–28), were isolated from the aqueous ethanol extract of the traditional Chinese herb Swertia mussotii. Their structures were elucidated via spectroscopic analyses including 2D NMR. The inhibition of α-glucosidase by the isolated xanthones was evaluated by an in vitro high-throughput screening assay. Our results indicated that 1,3,5,8-tetrahydroxyxanthone is the best inhibitor with an IC50 value of 5.33 ± 0.09 µM, while the O-glycosylated xanthones were poor α-glycosidase inhibitors.
研究领域:
药理学
·
天然产物化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHINESE JOURNAL OF CHEMISTRY
·
2015
·Vol. 33
·期 4
·409-412
·
IF 1.578
Dazhao Sun,Guofang Jiang,Zongbo Xie,Zhanggao Le
A novel methodology for the synthesis of bis(indolyl)methanes by the reaction of aromatic aldehydes and indole in water has been developed, and a series of desired products were obtained in moderate to excellent yields (from 65% to 97%) using 1.2 mg/mL α -chymotrypsin as biocatalyst.
研究领域:
有机化学
·
生物催化
·
绿色化学
✓ 已验证
产品关联
DOI
高影响因子
Nanomaterials
·
2021
·Vol. 11
·期 4
·890
·
IF 5.076
Yong Li,Qifeng Kuang,Xiaoling Men,Shenggang Wang,Da Li,Chuljin Choi,Zhidong Zhang
α″-Fe16N2nanomaterials with a shape anisotropy for high coercivity performance are of interest in potential applications such as rare-earth-free permanent magnets, which are difficult to synthesize in situ anisotropic growth. Here, we develop a new and facile one-pot microemulsion method with Fe(CO)5as the iron source and tetraethylenepentamine (TEPA) as the N/C source at low synthesis temperatures to fabricate carbon-coated tetragonal α″-Fe16N2nanocones. Magnetocrystalline anisotropy energy is suggested as the driving force for the anisotropic growth of α″-Fe16N2@C nanocones because the easy magnetization direction of tetragonal α″-Fe16N2nanocrystals is along the c axis. The α″-Fe16N2@C nanocones agglomerate to form a fan-like microstructure, in which the thin ends of nanocones direct to its center, due to the magnetostatic energy. The lengths of α″-Fe16N2@C nanocones are ~200 nm and the diameters vary from ~10 nm on one end to ~40 nm on the other end. Carbon shells with a thickness of 2–3 nm protect α″-Fe16N2nanocones from oxidation in air atmosphere. The α″-Fe16N2@C nanocones synthesized at 433 K show a room-temperature saturation magnetization of 82.6 emu/g and a coercive force of 320 Oe.Keywords:α″-Fe16N2;permanent magnetic material;one-dimensional nanocones;core/shell structure;anisotropic growth;chemical solution method
研究领域:
材料科学
·
物理学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）