JOURNAL OF MOLECULAR STRUCTURE
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2017
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IF 1.753
Yan Shi,Xue-Jie Tan,Dian-Xiang Xing,Qi-Cheng Sui,Bin Liu,Wen-Quan Feng,Yun Liu
In this manuscript, we report the synthesis, NMR and single-crystal structures of three propylene linking dimers related with the hydrolytic degradation of one 5,6-dehydronorcantharimide dimer. Special attention was paid to the conformation of propylene linkers in order to understand their changes in the reaction. Statistical analysis of CSD database revealed that a-a, g-a and g-g conformations may have similar stability in most cases and various complicated unpredictable non-covalent interactions may play important role in the formation of final rotamers . In order to reproduce all stable conformations and the energy barriers separating them, full range two-dimensional fully relaxed potential-energy surfaces (PES) scans of six ‘propylene linker’ dimers were calculated starting from the most stable crystal structures. The PES were scanned along both bridge C C single bond torsional angles (denoted as θ 1 and θ 2 ), while all other internal coordinates were optimized at the DFT/B3LYP/3-21G* level in gas phase. Then all energy minima were re-optimized again at the DFT/B3LYP/6-311 + G(d,p) level both in gas and ethanol solutions in order to evaluate the really stable rotamers. At last, 1D or 2D relaxed PES scans were performed between local stable rotamers to get reliable energy barriers. This method represents a less time-consuming and more reliable approach to the determination of conformational stability of propanediyl bridging chains. The combination of experimental, statistical and theoretical results shows that the observed conformation is jointly determined by the energy levels of the minima, energy barriers separating them, non-covalent interactions and somewhat randomness.
研究领域:
有机化学
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计算化学
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结构化学
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物理有机化学
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高影响因子
Molecular Catalysis
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2026
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IF 4.3
Yanping Zhang,Yi Zeng,Qingyin Wang,Gongying Wang,Wei Bai,Weixin Qian
Intrinsic acidity vs. accessibility in biomass dehydration is investigated. • TOF diverges from macroscopic yield in sorbitol dehydration. • The para-isomer gives the highest yield (∼74%) despite its lower site-normalized TOF. • Highly accessible acid-site density and balanced adsorption behavior contribute to the para-isomer's performance. This study investigates how intrinsic acid-site activity and spatial accessibility jointly regulate biomass dehydration. Using position-isomeric sulfonated carbon catalysts, namely 2-, 3-, and 4-CBC-PhSO₃H, we demonstrate a divergence between microscopic site activity and macroscopic catalytic performance in sorbitol dehydration. Kinetic analysis shows that the ortho-isomer exhibits the highest site-normalized turnover frequency (TOF), whereas the para-isomer achieves the highest overall isosorbide yield of approximately 74%. This difference arises from a synergistic balance between intrinsic reactivity and accessible acid-site density: the lower steric hindrance of the para-configuration favors a higher density of effective acid sites, which compensates for its lower single-site TOF. Theoretical calculations further suggest that substitution position affects proton dissociation, charge distribution, and adsorption behavior. In particular, the para-isomer maintains favorable interactions with organic reactants/intermediates while showing relatively weak water binding, which may help reduce competitive water adsorption during dehydration. These findings highlight that the catalytic performance of carbon-based solid acids is governed by the combined effects of intrinsic acidity, spatial accessibility, acid-site density, and interfacial adsorption behavior, guiding the rational design of robust solid acid catalysts for biomass conversion. Download: Download high-res image (210KB) Download: Download full-size image
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Surfaces and Interfaces
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2026
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IF 6
Peixin Li,Yaotian Yan,Zilong Zhang,Ziyao Huang,Haohan Wang,Tianlei Zhang,Liang Qiao,Jian Cao,Junlei Qi
SiO 2f /SiO 2 composites offer excellent dielectric and thermal stability, but reliable integration remains difficult due to the limitations of conventional metal brazes, including CTE mismatch and electrical conductivity. This study developed a novel all-dielectric brazing material, Bi 2 O 3 -B 2 O 3 (BB) glass, for joining SiO 2f /SiO 2 composite materials. The BB glass synthesized via melt-quenching exhibits an amorphous structure, a low glass transition temperature (T g =403°C), and an adjustable CTE (7-9×10 -6 /°C). Wetting experiments demonstrate excellent spreading on the SiO 2f /SiO 2 surface, with a contact angle as low as 16°. Density functional theory (DFT) analysis reveals that the formation of Bi-O-Si bonds and B-O-Si networks at the interface enhances the bonding strength. Differential charge density and density of states (DOS) results indicate that the electronic structure of BB glass improves dielectric response and reduces insertion loss in the GHz frequency band. BB glass overcomes the shortcomings of traditional brazing materials, providing a theoretical and technical foundation for reliable joining of SiO 2f /SiO 2 composite materials in extreme environments. Download: Download high-res image (353KB) Download: Download full-size image
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NEW JOURNAL OF CHEMISTRY
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2023
·Vol. 47
·期 29
·13952-13962
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IF 3.3
Dehong Bai,Ziyu Xue,Shaohui Li,Ran Meng,Dongxia Zhang,Xibin Zhou
Chromate (Cr(VI)) is a highly toxic heavy metal ion that not only endangers human health but also causes environmental pollution. To control and remove Cr(VI) from water more effectively, we report a simple, novel, and rapid detection technique for Cr(VI) in water based on an iron-manganese bimetal-metal organic framework (FexMny-MOF). Firstly, the synthesized FexMny-MOF has a large specific surface area and porosity; for the first time, an MOF with dual mimic enzyme properties is reported, which can catalyze the oxidation of 3,3′,5,5′-tetramethylbenzidine (TMB) to the blue product in the presence or absence of H2O2. Interestingly, the mimic enzyme properties of FexMny-MOF are enhanced than those of Fe-MOF and Mn-MOF. The free energies of elementary reactions and adsorption energies (Eads) of H2O2 and O2 adsorbed on different materials were calculated by density functional theory (DFT) to verify the mechanism of action of FexMny-MOF. The Fe1Mn1-MOF mimics oxidase-like oxidation of TMB; 8-hydroxyquinoline (8-HQ) is used as the inhibitor of TMB oxidation, and the specific interaction between 8-HQ and Cr(VI) weakens the inhibition of 8-HQ on TMB oxidation to achieve the detection of Cr(VI). The established method has high sensitivity and selectivity with a detection limit of 51 nM and a linear range of 80–3500 nM. This method has been successfully applied to the determination of Cr(VI) in tap water and the Yellow River, showing its great potential in environmental monitoring.
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CHEMOSPHERE
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2022
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IF 8.943
Jie Yao,Zekun Dong,Xincheng Ye,Jiaqi Yang,Yan Jia,Yan Zhang,Hongyuan Liu
Electrochemically activated peroxymonosulfate with mixed metal oxide electrodes (EA-PMS-MMO/MMO) is an emerging advanced oxidation process . It performed well on the degradation of sulfadiazine (SDZ), whose removal rate reached 81.13% within 30 min. Both the MMO anode and cathode played an irreplaceable role in PMS activation . HO • , SO 4 •- , O 2 •- and 1 O 2 were confirmed to be the major reactive species in the system, among which 1 O 2 was the most abundant. The generation mechanism of the reactive species and the overall mechanism of the system were proposed. Four degradation pathways of SDZ were speculated based on density functional theory . The acute and chronic toxicity of SDZ and its degradation intermediates was evaluated by the quantitative structure-activity relationship method, and the overall toxicity was significantly reduced after the degradation by EA-PMS-MMO/MMO. The results show that EA-PMS-MMO/MMO affords a reliable technology for the degradation of organic contaminants and has promising potential for application.
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PubMed
高影响因子
Journal of Environmental Chemical Engineering
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2022
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IF 7.968
Shoubing Chai,Yingjie Li,Wan Zhang,Zirui He
In carbonation stage of calcium looping process, NO could be reduced by CO using CaO as a catalyst, allowing simultaneous CO 2 and NO removal. However, to achieve efficient NO removal, the required CO/NO molar ratio in the carbonator is very high (up to 30:1), which leads to lots of unreacted CO in the exhaust gas. In this work, to maintain high efficiency of NO removal at low CO concentration in carbonator, Ce-doped CaO was employed to simultaneously enhance NO and CO 2 removal performance. The effects of Ce-doped CaO on simultaneous CO 2 and NO removal in bubbling fluidized bed reactor were investigated during the carbonation stage of calcium looping process. When the molar ratio of CO/NO is about 3.57:1, Ce-doped CaO obtains an 83% CO 2 capture efficiency and a 97% NO removal efficiency in 20 cycles in chemical reaction controlling stage. The average CO concentration in exhaust gas of Ce-CaO was reduced by 79% at the same NO removal efficiency as Mn-doped CaO. The presence of Ce 3+ makes the charge imbalance of the material, resulting in more charge transfer from the Ce-CaO surface to the molecules. The density functional theory reveals that Ce doping reduces the energy barriers of the conversion of NO to N 2 and the CO 2 adsorption, promoting the simultaneous NO/CO 2 removal in carbonation stage. Therefore, under a low molar ratio of CO/NO in carbonation stage of calcium looping, Ce considerably improves the simultaneous CO 2 and NO removal action of CO and CaO.
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JOURNAL OF HAZARDOUS MATERIALS
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2023
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IF 13.6
Shi-Xian Guan,Tao Xu,Jian-Yong Zhang,You-Guo Luo,Xingwu Zhai,Na Zhang,Yong-Zheng Fang,Qin-Fei Ke
Herein, we developed a multimodal antibacterial nanoplatform via synergism effect including knife-effect, photothermal, photocatalytic induced reactive oxygen species (ROS), and Cu 2+ inherent attribute. Typically, 0.8-TC/Cu-NS possesses higher photothermal property with the higher photothermal conversion efficiency of 24% and the moderate temperature up to 97 °C. Meanwhile, 0.8-TC/Cu-NS exhibits the more active ROS, 1 O 2 and ·O 2 - . Hence, 0.8-TC/Cu-NS possesses best antibacterial properties against S. aureus and E. coli in vitro with efficiency of 99.94%/99.97% under near-infrared (NIR) light, respectively. In the therapeutic practical use for wound healing of Kunming mice, this system exhibits outstanding curing capacity and good biocompatibility. Based on the electron configuration measurement and density functional theory (DFT) simulation, it is confirmed that the electrons on CB of Cu-TCPP flow fleetingly to MXene trough the interface, with redistribution of charge and band upward bending over Cu-TCPP. As a result, the self-assembled 2D/2D interfacial Schottky junction have made great favor to accelerate photogenerated charges mobility, hamper charge recombination, and increases the photothermal/photocatalytic activity. This work gives us a hint to mostly design the multimodal synergistic nanoplatform under NIR light in biological applications without drug resistance.
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高影响因子
JOURNAL OF APPLIED PHYSICS
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2023
·Vol. 134
·期 8
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IF 3.2
Li Gaojie,Zhang Linqi,Du Kai,Wang Xinxin,Yin Menghao
Reducing the working temperature and increasing sensitivity and selectivity has always been a research hotspot in the field of MOS based gas sensors. In this work, improved triethylamine (TEA) sensing performance and mechanism of SnO 2 by doping Pd have been investigated. SnO 2 nanoparticles and Pd-SnO 2 with different doping amounts of Pd (0%, 0.1%, 0.3%, 0.5%, and 0.7%) were successfully prepared by the hydrothermal method. The size of SnO 2 nanoparticles is very uniform (∼15 nm). The SnO 2 sensor exhibited the highest sensitivity to ethanol at 290 °C. After Pd doping, Pd/SnO 2 sensors not only reduced the optimum working temperature but transformed selectivity from ethanol to TEA. In the Pd-SnO 2 system, the 0.5Pd-SnO 2 sensor exhibited high sensitivity (61), fast response-recovery properties (16 s/6 s) to 50 ppm TEA, lower detection limits (0.1 ppm), good repeatability, and higher selectivity. Furthermore, based on density functional theory calculations, the improved TEA sensing performance of 0.5Pd-SnO 2 sensors can be attributed to the improved surface activity of SnO 2 by Pd doping and the catalytic activation of O 2 and TEA by Pd.
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高影响因子
JOURNAL OF MOLECULAR LIQUIDS
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2021
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IF 6.165
Bingqiao Yang,Pengliang Huang,Qing An
A small molecular triazole derivative called AMT (3-amino-5-mercapto-1,2,4-triazole) was explored as a novel and efficient chalcopyrite depressant in the preferential flotation of chalcopyrite from molybdenite. The flotation performances were comprehensively investigated via micro-flotation tests of singe and mixed minerals with and without Cu collector. The adsorption mechanisms were determined in terms of contact angle, adsorption capacity, and zeta potential, Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS) and DFT calculations. Single mineral flotation results illustrated that the AMT selectively depressed chalcopyrite over a wide range of pH values. Particularly, AMT was able to depress chalcopyrite even in the presence of sodium isobutyl xanthate (SIBX). The contact angle, adsorption capacity, zeta potential, and FTIR results suggested that AMT was preferentially adsorbed on chalcopyrite surface, but it barely interacted with molybdenite. XPS tests and DFT calculations demonstrated that AMT was chemically adsorbed on chalcopyrite surface through the hybridization of S (1) and N (1) 2p orbitals of AMT with the Cu (1) 3d orbital. The bonding between S (1) atom and Cu (1) was much stronger than that between N (1) and Cu (1). Thus, AMT exhibited good potential as a novel depressant due to its excellent selectivity and practicability.
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Journal of Environmental Chemical Engineering
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2021
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IF 5.909
Xiaoxiao Ding,Weihong Jiao,Yatao Yang,Zequan Zeng,Zhanggen Huang
Activated cokes integrated removal technologies have been widely used to abate polychlorinated dibenzo-p-dioxins and polychlorinated dibenzofurans (PCDD/Fs) in sintering flue gas . A series of comparative adsorption experiments were performed by using nitric acid (HNO 3 ) treated activated coke with dibenzofuran as model pollutants. The physicochemical properties of activated cokes were analyzed by using various characterization methods. Combined with the results of experiments, the interactions of typical oxygenated groups with dibenzofuran were also calculated by density functional theory to reveal the nature relationships among the textural properties, oxygenated functional groups and dibenzofuran adsorption behaviors. It was demonstrated through adsorption experiments that adsorption capacity decreased with the enhanced oxidation degrees of activated cokes. Especially the adsorption capacities of activated cokes were probably deteriorated by the hydrophilic carboxyl and anhydride groups. In contrast, a higher adsorption rate was obtained with the increasing oxidation degrees. It was revealed through the density functional theory analysis that physical adsorption dominated the adsorption of dibenzofuran on activated cokes, and dibenzofuran was adsorbed preferentially on the activated cokes with oxygenated groups. Moreover, the formation of oxygenated groups increased the adsorption energy of dibenzofuran on activated cokes and accelerated the adsorption process . However, the enhanced competitive adsorption of oxygen (O 2 ) also led to the reduction of adsorption capacity for dibenzofuran. This study not only gives a sophisticated understanding for the relationship between surface oxygenated groups and dioxins adsorption abatement but also offers referential guidance for the design of carbonaceous adsorbent suitable for the adsorption of PCDD/Fs.
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SEPARATION AND PURIFICATION TECHNOLOGY
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2021
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IF 7.312
Jie Huang,Bin Huang,Tianxiang Jin,Zhirong Liu,Dejuan Huang,Yong Qian
The extraction of U(VI) from nuclear wastewater is of great importance for environmental protection. In this work, we try to remove uranium ions from uranium-containing wastewater by electrosorption. In order to improve the adsorption capacity and selectivity of the adsorption materials, the complex of chitosan and phytic acid (CSPA) was used as electrode material. The experimental results showed that the introduction of phytic acid can efficiently improve the adsorption capacity, adsorption selectivity and reusability of chitosan. The maximum adsorption capacity of CSPA was 429.1 mg/g and the theoretical maximum sorption capacity reached up to 572.1 mg/g. Moreover, the electrosorption capacity of CSPA for U(VI) was 68.6% of the total electrosorption capacity in the presence of competitive ions. After 5 cycles of reuse, CSPA still maintained 86.6% of its initial sorption capacity. Furthermore, we found that the selective adsorption mechanism of uranium ions was related to the inner-sphere complexation between UO 2 2+ and the O atom of P O group according to the experimental analysis and the DFT calculation results. This work provided a novel strategy for effective removal of uranium (VI) from uranium-containing wastewater.
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JOURNAL OF MOLECULAR STRUCTURE
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2022
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IF 3.841
Wan-ping Chen,Run-quan Wang,Yue-rong Zhang,Kai Song,Yuan Tian,Jia-xian Li,Guo-ying Wang,Gao-feng Shi
In this article, the scavenging ability of hypericin on hydroxyl radicals was evaluated by UV spectra, HPLC and fluorescence spectra. The reaction mechanism of the scavenging of free radicals by hypericin was also investigated. The Gaussian calculations obtained for the spatial structure and electrostatic potential of hypericin revealed that the active site for the reaction of hypericin with hydroxyl radicals is on the phenolic hydroxyl group of hypericin. The dissociation energy, spin density and frontline orbitals of the dehydrogenated hypericin radicals yielded that hypericin 7-OH and 7′ -OH are most likely to react with hydroxyl radicals. the transition state structure, enthalpy change and Gibbs free energy change and energy change of the reaction between hypericin and hydroxyl radicals,and the results of the above calculations indicate that hypericin 7-OH and 7′ -OH have the highest activity, can be directly involved in the scavenging process of radicals, followed by 5-OH and 5′ -OH, and finally 4-OH (4′ - OH).In-depth study of the antioxidant mechanism of hypericin molecules can help to design and synthesize new antioxidants in a more rational way.
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危险品化学品经营许可证（带存储）