JOURNAL OF MATERIALS SCIENCE & TECHNOLOGY
·
2024
·
IF 11.2
Haizhen Liu,Liwen Lu,Hui Luo,Jiayi Deng,Guangxu Li,Hua Ning,Yi Fan,Cunke Huang,Zhiqiang Lan,Wenzheng Zhou,Jin Guo,Xinhua Wang
The Li-Mg-B-H composite (2LiBH 4 + MgH 2 ) is acknowledged as a promising material for hydrogen storage due to its large hydrogen capacity (11.4 wt.%). However, the sluggish kinetics and poor reversibility make it difficult to be practically used. In this work, the hydrogen storage performances of 2LiBH 4 + MgH 2 have been significantly improved by a hybrid of bulk NbC and layered Nb 4 C 3 MXene (denoted as “Nb-C”). The 2LiBH 4 + MgH 2 + 6 wt.% Nb-C can release 8.5 wt.% H 2 within 30 min at 400°C and the dehydrogenated composite can absorb 9.3 wt.% H 2 within 30 min at 350°C and 7.5 MPa H 2 . The reversible dehydrogenation capacity maintains at 8.4 wt.% after 24 cycles, with a capacity retention ratio of 95.4%. By contrast, the undoped 2LiBH 4 + MgH 2 suffers from serious capacity degradation, with the capacity decreased dramatically to 3.5 wt.% after 3 cycles. Microstructural studies revealed that the doped composite has uniform particle and elemental distributions and possesses various multiphase interfaces of LiH/MgB 2 /NbC/Nb 4 C 3 , which is beneficial to hydrogen diffusion during the hydrogen uptake and release process. Theoretical studies by first principle calculation presented an extended bond length of the Mg-H and B-H bonds in the 2LiBH 4 + MgH 2 + NbC system, which may also explain the improved hydrogen storage properties of 2LiBH 4 + MgH 2 by addition of Nb-C. This work provides new insights into the role of transition metal carbides in regulating the Li-Mg-B-H hydrogen storage materials both experimentally and theoretically.
研究领域:
材料科学
·
理论计算
✓ 已验证
产品关联
DOI
高影响因子
Chemical Engineering Journal Advances
·
2020
·
IF 0
Jiuhu Zhao,Zhengzhong Wen,Rongshu Zhu,Zhi Li,Ran Ding,Yongji Zhu,Tingkun Gu,Rong Yang,Zhenye Zhu
In this paper, In-metal oxide/H-Beta catalysts were synthesized by ion exchange method and In-Co 3 O 4 /H-Beta exhibited the highest catalytic activity for the selective catalytic reduction of NO x with CH 4 in presence of H 2 O and SO 2 . Thus, the synthesis conditions of In-Co 3 O 4 /H-Beta were optimized. The results showed that In-Co 3 O 4 /H-Beta exhibited excellent catalytic performance and high CH 4 selectively when the synthesis was carried out by ion exchange method, the ratio of Si and Al in H-Beta was 25, the ratio of Co 3 O 4 and H-Beta was 5:40, the concentration of ion exchange liquid was 0.033 M and calcination temperature was 500 °C. The NO x removal efficiency was about 87.6 % and N 2 selectivity could reach 96.3% in the presence of H 2 O and SO 2 . Through a series of characterizations, it was concluded that In-Co 3 O 4 /H-Beta owned stable catalyst structure, abundant Brønsted acid sites and the highest ratio of InO + /In 2 O 3 under the optimal synthesis conditions. In addition, the doped of Co 3 O 4 could inhibit the adsorption of sulfate species on the surface of In/H-Beta catalyst, leading to the excellent H 2 O and SO 2 resistance property.
研究领域:
环境科学
·
催化化学
✓ 已验证
DOI
Frontiers of Chemical Science and Engineering
·
2017
·Vol. 11
·期 4
·564-574
·
IF 1.712
Song Baodong,Li Yongqiang,Cao Gang,Sun Zhenhai,Han Xu
In the transformation of methanol to gasoline (MTG), the selectivity to gasoline and the aromatic content in the produced gasoline are important factors. The catalytic activities of steam-treated and non-steam-treated nano-scale H-ZSM-5 (NHZ5) catalysts impregnated with Ag(I), Zn(II) or P(V) have been investigated in a continuous flow fixed bed reactor. The NH 3 -TPD results showed that after impregnation, the Ag/NHZ5, Zn/NHZ5 and P/NHZ5 catalysts contained comparatively more strong, medium-strong and weak acid sites, respectively. Treatment with steam decreased the number of acid sites in all the catalysts, but the pore volumes in the catalysts were larger which improved carbon deposition resistance resulting in prolonged lifetimes. After 6 h of MTG reaction, the selectivity to gasoline for the steam-treated catalysts,
\(Ag_{H_2 O} /NHZ5\) , \(Zn_{H_2 O} /NHZ5\) and \(P_{H_2 O} /NHZ5\) were 70.5, 68.4 and 68.7 wt-%, respectively, whereas their respective aromatic contents in the produced gasoline were 61.9, 55.4 and 39.0 wt-%. Thus \(P_{H_2 O} /NHZ5\) is the most promising catalyst for MTG applications which can meet the China IV gasoline standard that the amount of aromatics in gasoline should be less than 48 wt-%.
研究领域:
催化化学
·
能源化工
·
材料科学
·
表面科学
·
石油炼制
✓ 已验证
DOI
高影响因子
JOURNAL OF ORGANIC CHEMISTRY
·
2024
·
IF 3.3
Jun-Feng Yang,Yun-Fei Liu,Lin-Lin Wei,Kai-Kai Qiao,Yan-Qiu Zhao,Lei Shi
The Minisci-type dehydrogenative coupling of N-heteroaromatic rings with inert C–H or Si–H partners via visible-light-catalyzed hydrogen atom transfer has been reported. This methodology allows the coupling reactions to be carried out in water as a solvent under air atmospheric conditions with visible-light illumination. A wide range of inert C–H and Si–H partners could be directly coupled with various N-aromatic heterocycles to deliver products in good to excellent yields.
研究领域:
有机化学
·
光化学
✓ 已验证
DOI
PubMed
高影响因子
International Journal of Minerals Metallurgy and Materials
·
2020
·Vol. 27
·期 2
·220-231
·
IF 1.713
Yang Tao,Liu Hui-juan,Bai Fan,Wang En-hui,Chen Jun-hong,Chou Kuo-Chih,Hou Xin-mei
Currently, developing supercapacitors with robust cycle stability and suitability for wide-temperature-range operations is still a huge challenge. In the present work, few-layer hexagonal boron nitride nanosheets (h-BNNSs) with a thickness of 2–4 atomic layers were fabricated via vacuum freeze-drying and nitridation. Then, the h-BNNSs/reduced graphene oxide (rGO) composite were further prepared using a hydrothermal method. Due to the combination of two two-dimensional (2D) van der Waals-bonded materials, the as-prepared h-BNNSs/rGO electrode exhibited robustness to wide-temperature-range operations from −10 to 50°C. When the electrodes worked in a neutral aqueous electrolyte (1 M Na 2 SO 4 ), they showed a great stable cycling performance with almost 107% reservation of the initial capacitance at 0°C and 111% at 50°C for 5000 charge—discharge cycles.
研究领域:
材料科学
·
能源存储技术
✓ 已验证
产品关联
DOI
高影响因子
Journal of Building Engineering
·
2025
·
IF 7.4
Juanhong Liu,Yayun Xi,Fanghui Han,Lingzhi Guo,Jinmei Hu
This study investigates the influence of aluminum incorporation on the chemical composition, morphology, silicate chain structure, and functional groups of C(-A)-S-H gel through micro- and nanoscale characterization. Based on experimental data, an atomic-scale structural model was constructed to closely reflect realistic Ca/Si and Al/Si ratios as well as Q n distributions, and to explore the effects of aluminum content on the mechanical properties and failure mechanisms of C-A-S-H at the atomic level. Results show that at low Al/Si ratios, Al can be effectively incorporated into the C-S-H gel; however, when Al/Si exceeds 0.10, Al-containing secondary phases start to precipitate. Al atoms bridge defects in silicate chains, extend the length of aluminosilicate chains, and form crosslinking structures along the z direction, with the degree of crosslinking increasing with Al content. Simulation results further indicate that Al incorporation restricts the diffusion pathways of interlayer water molecules, thereby enhancing gel structural integrity. Meanwhile, the formation of a three-dimensional crosslinking network substantially improves mechanical performance, significantly increasing Young's modulus and tensile strength in the y and z directions—especially enhancing interlayer cohesion and ductility along the z direction . Under tensile loading, stress-induced hydrolysis and bond depolymerization accelerate bond cleavage and hydroxyl formation within the C-A-S-H.
✓ 已验证
产品关联
DOI
高影响因子
RARE METALS
·
2023
·Vol. 43
·期 3
·1153-1166
·
IF 8.8
Lu Li-Wen,Luo Hui,Li Guang-Xu,Li Yun,Wang Xin-Hua,Huang Cun-Ke,Lan Zhi-Qiang,Zhou Wen-Zheng,Guo Jin,Ismail Mohammad,Liu Hai-Zhen
The Li-Mg-B-H composite (2LiBH 4 + MgH 2 ) has a high capacity of 11.4 wt% as a hydrogen storage material. However, the slow kinetics and poor cycling stability severely restrict its practical applications. In this work, a layered Nb 2 C MXene was first synthesized and then introduced to tailor the kinetics and cycling stability of the Li-Mg-B-H composite. The milled 2LiH + MgB 2 composites were initially hydrogenated to obtain the 2LiBH 4 + MgH 2 composites. The 2LiBH 4 + MgH 2 + 5 wt% Nb 2 C can release 9.0 wt% H 2 in 30 min at 400 °C, while it is only 2.7 wt% for the undoped 2LiBH 4 + MgH 2 . The dehydrogenation activation energies of MgH 2 and LiBH 4 are 123 and 154 kJ·mol −1 respectively for the 5 wt% Nb 2 C-doped composite, lower than the undoped composite (164 and 165 kJ·mol −1 ). The 2LiBH 4 + MgH 2 + 5 wt% Nb 2 C possesses excellent cycling stability, with the reversible capacity only slightly reduced from 9.4 wt% for the 1st cycle to 9.3 wt% for the 20th cycle. Nb 2 C keeps stable in the composite and acts as an efficient catalyst for the Li-Mg-B-H composite. It is believed that both the layered structure and the active Nb element contribute to the enhanced hydrogen storage performances of the Li-Mg-B-H composite. This work confirms that the Nb 2 C MXene with layered structure has a significant enhancing impact on the Li-Mg-B-H hydrogen storage materials, which is different from the bulk NbC. Graphical abstract
研究领域:
材料科学
·
能源化学
·
纳米催化
·
储氢技术
·
固体化学
✓ 已验证
DOI
高影响因子
CHEMISTRY-A EUROPEAN JOURNAL
·
2017
·Vol. 23
·期 41
·9831-9837
·
IF 5.317
Qiang Cao,Qing Yin,Qi Chen,Zhi-Bing Dong,Bao-Hang Han
Graphical Removed from the mix : The synthesis of fluorinated iron–porphyrin conjugated porous polymers through direct C−H arylation polymerization is described (see scheme). The application of these polymers as heterogeneous catalysts for Baeyer–Villiger oxidation is also discussed. By considering the high reactivity of fluorinated iron–porphyrin and good stability of porphyrin-based porous polymers, fluorinated iron–porphyrin conjugated porous polymers ( FPOP-3 – 6 ) were synthesized through direct C−H arylation polymerization. The obtained materials are chemically and thermally stable, of which FPOP-3 exhibits the highest Brunauer–Emmett–Teller specific surface area (about 840 m 2 g −1 ). For functional studies of the obtained polymers as heterogeneous catalysts, catalytic transformation of cycloketones into lactones by oxygen through Baeyer–Villiger oxidation was used as a model reaction. Fluorinated phenyl substituents of the iron–porphyrin not only are beneficial to the conversion, but also can stabilize the porphyrin to resist catalyst breakdown. The polymer FPOP-3 , with high porosity, exhibits the best catalytic efficiency and recycling effect. The recovered catalyst also shows good catalytic activities after recycling three times with a small loss in yield.
研究领域:
材料化学
·
催化化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF POLYMER SCIENCE PART A-POLYMER CHEMISTRY
·
2012
·Vol. 51
·期 6
·1405-1416
·
IF 3.919
Cheng-Guang Mu,Xiao-Dong Fan,Wei Tian,Yang Bai,Zhen Yang,Hao Yao,Heng Chen
We report on the synthesis of an H-shaped polymer bonding β-cyclodextrin (β-CD) at branch points and influences of attached β-CD on physical properties. First, a poly(ethylene glycol)(PEG)-based functional macroinitiator bearing two azidos and four chlorines at chain-ends (PEG-2N 3 (-4Cl)) was prepared via terminal modification reactions. Then, PEG-2N 3 (-4Cl) was applied to initiate the atom transfer radical polymerization of N-isopropylacrylamide, leading to the synthesis of an H-shaped block polymer with PEG as the central chain and poly( N -isopropylacrylamide) (PNIPAM) as side-arms (PEG-2N 3 (-4PNIPAM)). Azido groups were at the branch points of the polymer. Finally, the click reaction between PEG-2N 3 (-4PNIPAM) and alkynyl monosubstituted β-cyclodextrin (β-CD) afforded another H-shaped polymer with two β-CDs bonding at the polymer branch points (PEG-2CD(-4PNIPAM)). The glass transition temperature ( T g ) and lower critical solution temperature (LCST) of the H-shaped polymer increased after the attachment of β-CD. The self-assembly and thermal responsive behaviors, as well as the encapsulation behaviors of PEG-2CD(-4PNIPAM) were also altered. When temperature was below the LCSTs, PEG-2N 3 (-2PNIPAM) dissolved in water molecularly, whereas PEG-2CD(-4PNIPAM) could self-assemble into nano-sized micelles. After the LCST transitions, PEG-2N 3 (-4PNIPAM) aggregated into micron-sized unstable particles, whereas PEG-2CD(-4PNIPAM) transformed into PNIPAM-cored nanomicelles. Besides, PEG-2CD(-4PNIPAM) can encapsulate doxorubicin below its LCST due to the formation of micelles. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2013
研究领域:
高分子化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2024
·
IF 8.1
Lijie Fu,Juanjuan Gong,Hengyu Li,Jinhua Xiao,Bihong Lv,Xiaomin Wu,Zhiwei Huang,Zuoming Zhou,Guohua Jing
The regeneration of catalytic amine-based solvents using solid acid offers a promising approach to reduce energy consumption in CO 2 capture processes. Nickel-based solid acid catalysts, endowed with multiple Lewis acid sites, could enhance the efficiency of regeneration reactions. Nevertheless, the irregular pore structure of NiO and the deficiency in Brønsted acid sites posed significant challenges to the practical use of amine solvent regeneration in CO 2 vapor stripping processes. A highly effective solid acid catalyst, nickel-modified H-β (Ni/β), were synthesized to enhance CO 2 desorption from MEA solutions saturated with CO 2 . The catalyst with 1.25% Ni (1.25% Ni/β) exhibited the highest activity and stability, with a 43.19% increase in the amount of desorbed CO 2 and a 30.16% reduction in relative heat duty. The catalyst maintained excellent stability, enhancing the desorption performance of MEA after ten cyclic absorption–desorption experiments. According to theoretic calculations and experimental analyses, the incorporation of H-β zeolite significantly enhanced the specific surface area of the composite and introduced a substantial number of Brønsted acid sites. Concurrently, the introduction of metal nickel substituted the hydrogen proton on the hydroxyl groups of the H-β molecular sieve, increasing the Lewis acid sites and modulating the Brønsted-to-Lewis acid site ratio. The Brønsted acid sites functioned as proton donors, while the Lewis acid sites facilitated N-C bond cleavage, promoting carbamate decomposition and the deprotonation of protonated amines. This work presents a valuable solid acid catalyst for amine-based CO 2 capture and offers insights for developing innovative solid acids for various catalytic processes.
研究领域:
化学工程
·
环境科学
·
催化材料
✓ 已验证
产品关联
DOI
高影响因子
Frontiers in Neurology
·
2019
·
IF 2.635
Zhang Jie,Jiang Yunyao,Liu Nan,Shen Ting,Jung Hyo Won,Liu Jianxun,Yan Bing Chun
Senkyunolide-H (SEH), a major bioactive compound extracted from Ligusticum chuanxiong, has been reported to be effective in preventing cerebral ischemic stroke (CIS). In this study, we employed network pharmacology to reveal potential mechanism of SEH against CIS on a system level and confirmed the therapeutic effects of SEH on CIS by models of cerebral ischemia-reperfusion in vivo and in vitro. Through protein-protein interaction networks construction of SEH- and CIS-related targets, a total of 62 key targets were obtained by screening topological indices and analyzed for Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway enrichment. Gene Ontology analysis indicated that SEH might have a role in treating CIS via regulating some biological processes including regulation of transcription from RNA polymerase II promoter, epidermal growth factor receptor signaling pathway, phosphatidylinositol-mediated signaling, and some molecular function, such as transcription factor and protein phosphatase binding and nitric oxide synthase regulator activity. Meanwhile, the Kyoto Encyclopedia of Genes and Genomes analysis showed that phosphoinositide 3-kinase (PI3K)/protein kinase B (Akt) signaling pathway was significantly enriched. In addition, our result showed that SEH posttreatment significantly decreased the neurological scores, infarct volume, and neuronal death in the middle cerebral artery occlusion mice. Moreover, the PI3K/Akt/nuclear factor kappa B signaling pathway was activated by intragastric administration of 40 mg/kg SEH, as verified by Western blot. In vitro, treatment of PC12 cells with 100 μM SEH markedly reduced cell death induced by oxygen-glucose deprivation through the activation of PI3K/Akt/nuclear factor kappa B pathway, and the therapeutic effect of SEH was obviously inhibited by 10 μM LY294002. In summary, these results suggested that SEH carries a therapeutic potential in CIS involving multiple targets and pathways, and the most crucial mechanism might be through the activation of PI3K/Akt/nuclear factor kappa B (NF-κB) signaling pathway to inhibit inflammatory factor releases and increase the antiapoptosis capacity. Our study furnishes the future traditional Chinese medicine research with a network pharmacology framework.
研究领域:
药理学
·
神经科学
·
中药学
·
分子生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
EUROPEAN JOURNAL OF PHARMACEUTICAL SCIENCES
·
2024
·
IF 4.3
Chunmiao Wang,Zhaoquan Li,Honglan Zhai,Xiaoyan Shen,Fengming Li,Qiuping Zhang,Danrong Li,Huaxin Hou
Background Cytoplasmic epidermal growth factor receptor (EGFR) is overexpressed in both nasopharyngeal carcinoma (NPC) and triple-negative breast cancer (TNBC), while clinical outcome and prognosis vary greatly among patients treated with gefitinib, and all patients eventually develop resistance to this agent. Therefore, we propose a new concept for synthesizing multitarget compounds and reveal new therapeutic strategies for NPC and TNBC expressing EGFR. Methods Compound H was synthesized in our previous study. Molecular docking, and cell thermal shift assays (CETSAs) and drug affinity responsive target stability(DARTS) were used to confirm the binding of compound H to EGFR and GLUT1. Methylthiazolyldiphenyl-tetrazolium bromide(MTT), annexin V-PE assays, mitochondrial membrane potential (MMP) assays, and animal models were used to evaluate the inhibitory effect of compound H on TNBC cell lines. Energy metabolism tests, Western blotting, and immunofluorescence staining were performed to evaluate the synergistic effects on EGFR- and glucose transporter type 1(GLUT1)-mediated energy metabolism. Results Compound H can simultaneously act on the EGFR tyrosine kinase ATP-binding site and inhibit GLUT1-mediated energy metabolism, resulting in reductions in ATP, MMP, intra-cellular lactic acid, and EGFR nuclear transfer. The anti-tumor activity of compound H is significantly superior to the combination of GLUT1 inhibitor BAY876 and EGFR inhibitor gefitinib. Compound H has remarkable anti-proliferative effects on TNBC MDA-MB231 cells, and importantly, no obvious toxicity effects of compound H were found in vivo . Conclusions Synergistic effects of inhibition of EGFR- and GLUT1-mediated energy metabolism by compound H may present a new strategy for the treatment of TNBC and NPC.
研究领域:
肿瘤学
·
药理学
·
分子生物学
✓ 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）