RSC Advances
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2013
·Vol. 4
·期 6
·3082-3089
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IF 2.562
Weitong Cai,Hui Wang,Dalin Sun,Qingan Zhang,Xiangdong Yao,Min Zhu
Destabilization by the alkali metal hydroxides LiOH, NaOH, and KOH in the solid-state dehydrogenation of LiBH4 is reported. 6.5 wt% of hydrogen was liberated within 10 minutes at 250 °C. Destabilization originated from the interaction between H+ in [OH]− and H− in [BH4]−. A larger Pauling's electronegativity of the alkali metal (Li > Na > K) led to a greater acidity of the proton donor [OH]− site, and thus enhanced destabilization. The temperature of the predominant dehydrogenation was reduced to 207, 221, and 230 °C, for ball milled LiBH4–LiOH, 2LiBH4–NaOH, and 2LiBH4–KOH, respectively. The LiBH4: LiOH stoichiometry greatly affected the destabilization, by providing differing reaction pathways in LiBH4-xLiOH (x = 1, 1.36, 4). The incremental increase in the LiOH content of LiBH4-xLiOH increased the dehydrogenation rate, but the temperature increased from 207 °C (x = 1) to 250 °C (x = 4). 4.1 and 6.5 wt% of hydrogen was liberated within 10 minutes by LiBH4–LiOH and LiBH4–4LiOH, respectively. The incremental increase in dehydrogenation temperature was attributed to differing [BH4]−⋯[OH]− interactions, formed by the differing stoichiometric ratios.
研究领域:
材料科学
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化学
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DOI
高影响因子
RSC Advances
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2017
·Vol. 7
·期 36
·22485-22491
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IF 3.108
Hailiang Zhao,Shanshan Tang,Qun Zhang,Lin Du
The weak intermolecular interaction between 2,2,2-trifluoroethanol (TFE) and 3-chloro-2-methyl-1-propene (CMP) has been investigated by gas phase FTIR spectroscopy and DFT calculations. CMP offers two hydrogen bond docking sites to the hydrogen bond donor: the chlorine atom (O–H⋯Cl) and the CC π electron system (O–H⋯π). DFT calculations suggest that MeOH approaches CMP in five different orientations. The structural, energetic, and spectroscopic parameters of the most stable structures in each orientation were studied, and their binding energies range from −25.5 to −19.5 kJ mol−1. The docking to the π system is at least 1 kJ mol−1 more favored than the docking to the chlorine atom. The equilibrium constant for complexation (2.3 × 10−2) was determined from the experimental and calculated intensity of the OH-stretching transition. The Gibbs free energy of formation was found to be 9.3 kJ mol−1. The nature of the non-covalent interaction was analyzed with the atoms in molecules (AIM) method.
研究领域:
物理化学
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结构化学
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分子光谱学
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量子化学计算
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分子间相互作用
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高影响因子
Science China-Chemistry
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2017
·Vol. 61
·期 3
·276-280
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IF 4.132
Qi Guangyu,Wang Kai,Xiao Guanjun,Zou Bo
Pressure, as a thermodynamic parameter, provides an appropriate method to detect weak intermolecular interactions. The C–H···H–B dihydrogen bond is so weak that the experimental evidence of this interaction is still limited. A combination of in situ high pressure Raman spectra and angle-dispersive X-ray diffraction (ADXRD) experiments was utilized to explore the dihydrogen bonds in dimethylamine borane (DMAB). Both Raman and ADXRD measurements suggested that the crystal structure of DMAB is stable in the pressure region from 1 atm (1 atm=1.01325×10 5 Pa) to 0.54 GPa. The red shift of CH stretching and CH 3 distortion modes gave strong evidence for the existence of C–H···H–B dihydrogen bonds. Further analysis of Raman spectra and Hirshfeld surface confirmed our proposal. This work provided a deeper understanding of dihydrogen bonds. And we wish that high pressure could be applied to identify other unconfirmed hydrogen or dihydrogen bond.
研究领域:
化学
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材料科学
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晶体学
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高影响因子
JOURNAL OF ORGANIC CHEMISTRY
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2025
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IF 3.6
Jia-Wei Li,Shuai Shi,Xiao-Hong Chen,Mao-Gui Huang,Yong-Liang Ban,Hui Zhang,Yue-Jin Liu
Direct functionalization of native (N–H) indoles via C–H activation remains a challenge. Herein, we report a salicylaldehyde-promoted cobalt-catalyzed selective C2–H Heck reaction of native (N–H) indoles with both active and unactivated olefins in the presence of free N–H bonds. A series of structurally diverse C2-alkenylated native (N–H) indoles including natural product and drug derivatives were prepared directly and effectively without additional preprotection and deprotection procedures.
研究领域:
有机化学
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药物化学
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DOI
PubMed
高影响因子
FUEL
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2022
·
IF 8.035
Yueqing Wang,Hongxing Wang,Junbo Zhang,Hongyan Zheng,Long Huang,Yulei Zhu
Selectively converting fructose into furfural by H-beta catalyst is a very interesting catalytic process. However, it is a challenging task to clearly elucidate the roles of framework Al for selective scission of C C and C O bond. Herein, selective elimination of framework Al atoms is realized. Several detailed investigations showed that the framework Al species located in different sites play important role in furfural formation. The framework Al atoms of pristine H-beta mainly occupied at T1, T2, T5, T6 and T7 sites. These Al species at pore mouth can be removed by citric acid, while the treatment of nitric acid mainly eliminated the framework Al atoms from T2 and T7 sites. As for oxalic acid, the Al atoms occupied at T2, T5, T6 and T7 was primarily leached. Upon citric acid and nitric acid treatment afforded the similar yield of furfural, indicating that the formation of furfural could not be governed by these Al species at pore mouth, T2 and T7 sites. However, in the case of oxalic acid treatment, complete removal of the Al species on T2, T5, T6 and T7 sites decreased the yield of furfural. Thus, it is reasonably inferred that these Al atoms populated at T1 sites and intersecting channels is more encouraging for the splitting of C C bond, while the Al species occupied at T5, T6 sites and the larger straight channels is probably more favorable to scission of C O bond.
研究领域:
催化化学
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材料科学
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DOI
高影响因子
APPLIED CATALYSIS A-GENERAL
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2020
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IF 5.006
Haodong Duan,Xiaolei Xu,Kangwei Leng,Ge Guo,Qing Yu,Xinjin Li,Yuxi Han,Jun Gao,Zhongwei Wang
The characteristics of the reaction for the preparation of dichlorophenylphosphine (DCPP) via benzene and PCl 3 in the presence of AlCl 3 were studied. Some unique characteristics were observed when a catalytic amount of AlCl 3 was used. Namely, more than one mole of DCPP was obtained per mole AlCl 3 , the reaction solution was layered, and DCPP could be directly separated. Our mechanistic study showed that benzene reacted with PCl 3 to form DCPP-AlCl 3 , and DCPP-AlCl 3 dissociated into DCPP and AlCl 3 , continuing to catalyze this reaction. This resulted in the high catalytic efficiency of AlCl 3 . The layering of the reaction solution was caused by the immiscibility of DCPP-AlCl 3 with the raw materials, greatly facilitating the dissociation process of DCPP-AlCl 3 . The formation of diphenylphosphorus chloride (DPC) was due to a continuous Friedel-Crafts reaction between DCPP and benzene. DPC cooperated with AlCl 3 to form the stable coordination compound DPC-AlCl 3 that did not dissociate and was responsible for the deactivation of AlCl 3 .
研究领域:
有机化学
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催化化学
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高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2023
·
IF 9.9
Jia'ni Gong,Pengfei Bai,Yifu Zhang,Qiushi Wang,Jingjing Sun,Yanyan Liu,Hanmei Jiang,Ziyi Feng,Tao Hu,Changgong Meng
Molybdenum trioxide (MoO 3 ) has been widely studied in the energy storage field due to its various phase states and unique structural advantages. Among them, lamellar α -phase MoO 3 ( α -MoO 3 ) and tunnel-like h -phase MoO 3 ( h- MoO 3 ) have attracted much attention. In this study, we demonstrate that vanadate ion (VO 3 - ) can transform α -MoO 3 (a thermodynamically stable phase) to h -MoO 3 (a metastable phase) by altering the connection of [MoO 6 ] octahedra configurations. h -MoO 3 with VO 3 - inserted (referred to as h -MoO 3 -V) as the cathode material for aqueous zinc ion batteries (AZIBs) exhibits excellent Zn 2+ storage performances. The improvement in electrochemical properties is attributed to the open tunneling structure of the h -MoO 3 -V, which offers more active sites for Zn 2+ (de)intercalation and diffusion. As expected, the Zn// h -MoO 3 -V battery delivers specific capacity of 250 mAh·g −1 at 0.1 A·g −1 and rate capability (73% retention from 0.1 to 1 A·g −1 , 80 cycles), well exceeding those of Zn// h -MoO 3 and Zn// α -MoO 3 batteries. This study demonstrates that the tunneling structure of h -MoO 3 can be modulated by VO 3 - to enhance the electrochemical properties for AZIBs. Furthermore, it provides valuable insights for the synthesis, development and future applications of h -MoO 3 .
研究领域:
材料科学
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电化学
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能源存储
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DOI
PubMed
高影响因子
Asian Journal of Organic Chemistry
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2018
·Vol. 7
·期 8
·1626-1634
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IF 2.496
Wen-Jing Pan,Zhong-Xia Wang
Graphical Cut my bonds into pieces : The C−H benzylation of oxazoles and benzoxazoles with benzyl trimethylammonium triflates was performed under mild conditions via Pd-catalyzed C−H/C−N cleavage. The method exhibits a wide scope of substrates and good compatibility of functional groups. The C−H benzylation of oxazoles and benzoxazoles with benzylic ammonium triflates was performed in reasonable to good yields via Pd-catalyzed C−H/C−N cleavage. The method exhibits a wide scope of azoles and benzylic ammonium triflates. A range of functional groups including F, CF 3 , COOEt, C(O)NMe 2 , OMe, OPh, pyridyl and thienyl groups can be tolerated.
研究领域:
有机化学
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药物化学
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DOI
高影响因子
International Journal of Environmental Research and Public Health
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2013
·Vol. 10
·期 7
·2897-2905
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IF 1.998
Juan Peng,Shanshan Song,Liguang Xu,Wei Ma,Liqiang Liu,Hua Kuang,Chuanlai Xu
We have established a highly sensitive sandwich enzyme-linked immunosorbent assay (ELISA) based on two monoclonal antibodies (mAb) to measure the content of the major peanut allergen Ara h 1 in foods. Two mAbs were selected out of 12 murine hybridoma cells secreting Ara h 1-specific antibody. Using mAb 6 as the capture antibody and HRP-labelled mAb 4 as the detection antibody, the limit of detection (LOD) the assay was 0.34 ng/mL. Cross-reaction analysis showed that this method was strongly specific and had no cross-reactions with Ara h 2, pea protein or soy protein. Sample analysis showed that this ELISA was a useful tool to monitor peanut allergens in food products by measuring Ara h 1 content.Keywords:peanut allergen;Ara h 1;monoclonal antibody;sandwich ELISA
研究领域:
食品科学
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免疫学
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分析化学
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DOI
PubMed
高影响因子
Nanomaterials
·
2019
·Vol. 9
·期 7
·1051
·
IF 4.034
Xiu Wang,Zhihuai Yu,Liang Jiao,Huiyang Bian,Weisheng Yang,Weibing Wu,Huining Xiao,Hongqi Dai
Hexagonal boron nitride (h-BN)-based heat-spreading materials have drawn considerable attention in electronic diaphragm and packaging fields because of their high thermal conductivity and desired electrical insulation properties. However, the traditional approach to fabricate thermally conductive composites usually suffers from low thermal conductivity, and cannot meet the requirement of thermal management. In this work, novel h-BN/cellulose-nano fiber (CNF) composite films with excellent thermal conductivity in through plane and electrical insulation properties are fabricated via an innovative process, i.e., the perfusion of h-BN into porous three dimensional (3D) CNF aerogel skeleton to form the h-BN thermally conductive pathways by filling the CNF aerogel voids. When at an h-BN loading of 9.51 vol %, the thermal conductivity of h-BN/CNF aerogel perfusion composite film is 1.488 W·m−1·K−1at through plane, an increase by 260.3%. The volume resistivity is 3.83 × 1014Ω·cm, superior to that of synthetic polymer materials (about 109~1013Ω·cm). Therefore, the resulting h-BN/CNF film is very promising to replace the traditional synthetic polymer materials for a broad spectrum of applications, including the field of electronics.Keywords:CNF aerogel;perfusion;h-BN;thermal conductivity;electrical insulation
研究领域:
材料科学
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电子工程
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DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Shuangxi Lin,Longchen Gong,Ning Zhao,Huibo Zhao,Feigang Zhao,Yang Bai,Zhenhua Li,Wen Liu
Modulating metal-support interactions is critical for improving catalytic activity and product selectivity for CO 2 hydrogenation. Such modulation can be achieved by modifying the metal nanoparticles as well as the supports. Here, we prepared a novel catalyst, in which Ni nanoparticles were dispersed on CeO 2 and hexagonal boron nitride (h-BN) hybrid supports. The introduction of h-BN to Ni/CeO 2 -BN effectively improves the dispersion of Ni nanoparticles. More importantly, the abundant Ni-CeO 2 interfacial sites with enriched oxygen vacancies are formed over h-BN edge sites. The dispersed Ni species are anchored on CeO 2 via a unique interfacial structure, with electron-rich Ni (Ni δ− ) species. At the interfacial sites on Ni/CeO 2 -BN, the synergy between oxygen vacancies and Ni δ− , which enhances CO 2 activation and H 2 dissociation, respectively, renders superior catalytic performance for CO 2 methanation. In situ DRIFTS suggests formate as key rate-limiting intermediates on Ni-CeO 2 sites, while the formation of B-H bonds further promotes hydrogen activation and subsequently the catalytic performance. The modulation of metal-support interactions by spatial confinement effect by BN offers a new paradigm for designing metal/oxide catalysts for chemical transformations that requires bifunctionality as CO 2 hydrogenation.
研究领域:
催化化学
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材料科学
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DOI
高影响因子
Journal of Physical Chemistry C
·
2021
·
IF 4.126
Dai Sun,Yu-Le Wang,Peng-Yue Zhu,Hai-Tao Ren,Yong Liu,Song-Hai Wu,Shao-Yi Jia,Xu Han
Mechanisms involved in the photocatalytic oxidation of As(III) are complicated in that various oxidizing species (such as h+, •OH, and O2•–) have been suggested to play important roles in different photocatalytic systems. In this study, Bi2.15WO6 shows high reactivity in the photocatalytic oxidation of As(III) under visible light. Quenching experiments indicate that apart from h+, the surface superoxo (≡Bi–OO•) and peroxo species (≡Bi–OOH) formed on Bi2.15WO6 also contribute to As(III) oxidation. The increased production of H2O2 with increasingly consumed As(III) or with the addition of H-donors such as glucose and various phenolics further reveals that H-abstraction from As(III) or H-donors to ≡Bi–OO• and then to ≡Bi–OOH is an important pathway involved in H2O2 production and As(III) oxidation. In addition, various characterizations confirm that the As(III)–O–Bi(III) surface complexes formed on Bi2.15WO6 enhance the photocatalytic reactivity of Bi2.15WO6 via the ligand-to-metal charge transfer pathway. We therefore suggest that dissolved oxygen is sequentially reduced to ≡Bi–OO• and then to ≡Bi–OOH on Bi2.15WO6, accompanied by H-abstraction from adsorbed or aqueous As(III) to ≡Bi–OO• and ≡Bi–OOH with the formation of H2O2 and the oxidation of As(III). This work enriches our understanding of the mechanisms involved in the photocatalytic oxidation of As(III).
研究领域:
环境科学
·
材料科学
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DOI
高影响因子
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