FUEL
·
2023
·
IF 7.4
Zehao Han,Lun Pan,Kang Xue,Jisheng Xu,Qing Liu,Ying Xu,Zhouyang Shen,Xiangwen Zhang,Ji-Jun Zou
Polycyclic alkanes are not only the important components of high-density fuels, but also can be used to cool the overheating parts of hypersonic vehicle through catalytic endothermic dehydrogenation reaction. However, the dehydrogenation performances of cycloalkanes with different molecule structures vary widely. Herein, we investigated the effects of cycloalkane structures, including the length of branched chains, the number of branched chains, the number of rings, and the shape of rings, on the dehydrogenation performance. The results show that cyclohexane (CH) exhibits the best dehydrogenation performance (600 °C, 3 MPa) with >99% conversion, >99% benzene selectivity, and highest total heat sink of 4.47 MJ/kg. The branched chains, ring number and five-membered rings all have negative effects on dehydrogenation. Among them, the number of rings has the minimum negative impact. Moreover, we correlated the density, volumetric net heat of combustion (NHOC) and heat sink with the molecular structure of the cyclic alkanes and found that the polycyclic alkanes with low H/C ratio and high M have both high density, high volumetric NHOC and high heat sink. This work can provide guidance for development and design of advanced fuels for endothermic dehydrogenation.
研究领域:
化学工程
·
燃料科学
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产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2024
·
IF 6.3
Bo Li,Xuxia Zhang,Xin Yang,Yuhong Xu,Weilong Chun,Qingqing Hao,Jianbo Zhang,Zhuo Li,Huiyong Chen,Xiaoxun Ma
Ti 3+ defective TiO 2 nanoparticles (TiO 2 -NPs) were synthesized through slow hydrolyzation of tetrabutyl titanate and low-temperature annealing, followed by loading on self-pillared pentasil (SPP) zeolite nanosheets to construct a TiO 2 /zeolite hybrid composite by solid-state dispersion. The obtained TiO 2 -NPs/SPP composite exhibited a distinct red-shift in the UV–vis absorption spectrum and a significantly reduced band gap due to the introduced Ti 3+ defects and the consequent oxygen vacancies (V O ), leading to an enhanced visible-light responsivity. The diverse porosity and house-of-cards nanosheet morphology of the SPP support not only promoted the efficient loading and stable immobilization of TiO 2 -NPs nanoparicles through micropore migration and surface adhesion but also endowed the adsorbability to the TiO 2 -NPs/SPP composite. The adsorptive photodegradation of methylene blue (MB) was used to evaluated the photocatalytic performance of TiO 2 -NPs/SPP, and a 95.6 % degradation rate of MB was observed after 3 h illumination with visible-light. The adsorptive effect strongly promoted the accessibility of MB molecules to the active TiO 2 species, leading to a remarkable enhancement in degradation efficiency. Moreover, a superior recyclability embodied in the retention of 96.4 % photocatalytic activity after three regeneration cycles indicated the TiO 2 -NPs/SPP composite to be practical for water pollutant degradation.
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
Reaction Chemistry & Engineering
·
2025
·
IF 3.1
Xueqian Zhang,Jiasong Yan,Shuai Yuan,Shanqing Yu,Qingyu Liu,Xikai Wang,Rui Li
Whether cycloalkanes undergo six- or five-membered ring-opening reaction pathways remains controversial. In this work, the catalytic cracking reactions of cyclohexene and 1-methylcyclopentene, as model compounds, were investigated in a pulse microreactor. The characteristics of the reactions of the two model compounds were compared in terms of isomerization, cracking, and hydrogen transfer reaction, and the reasons for the differences in their catalytic reactions were analyzed in combination with thermodynamic and molecular simulation calculations. The results have shown that the catalytic cracking product distributions of cyclohexene and 1-methylcyclopentene were similar owing to their easy mutual isomerization; the five-membered ring-opening cracking pathway was more thermodynamically advantageous than that of six-membered ring-opening cracking, and therefore, the yield of the ring-opening cracking product of 1-methylcyclopentene was comparatively higher; the main products of the hydrogen transfer reaction of the two compounds were alkanes and aromatic hydrocarbons. By comparing the product distributions and reaction activation energies, the ring-opening reaction pathways were clarified, and the catalytic cracking reaction networks of cyclohexene and 1-methylcyclopentene were established.
研究领域:
化学
·
催化反应
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产品关联
DOI
高影响因子
POLYMER ENGINEERING AND SCIENCE
·
2023
·Vol. 63
·期 9
·3025-3036
·
IF 3.2
Xiang-nan Liu,Yuan-meng Wang,Xiang-yuan Li,Jun-ying Zhang,Jing-bo Zhao
A new synthesis route different from convenient epoxy/CO 2 method was established to synthesize a five-membered dicyclocarbonate of bisphenol A (BisA-5dCC), and its hybrid non-isocyanate polyurethanes with epoxy resins (HNIPUs) were reported. Bisphenol A was first reacted with 3-chloro-1,2-propanediol to prepare a bisphenol A tetraol (BisA-4OH), and then was reacted with excess diethyl carbonate to obtain BisA-5dCC. Three polyhydroxyurethanes with H 2 N-terminal groups (PHUs) were synthesized from the aminolysis polyaddition of BisA-5dCC and excess hexanediamine. The PHUs were crosslinked with 1,4-butanediol diglycidyl ether and bisphenol A diglycidyl ether, respectively, and different HNIPUs were prepared. The structures of BisA-4OH, BisA-5dCC, and PHUs were confirmed, and the HNIPUs were characterized by Fourier transform infrared, differential scanning calorimetry, dynamic mechanical analysis, thermogravimetric analysis, and tensile tests. HNIPUs prepared from aromatic epoxy showed higher T g (up to 81°C) and better tensile strength (as high as 60 MPa) than those from aliphatic epoxy. High-performance HNIPUs with excellent thermal and mechanical properties were successfully synthesized. Highlights Dicyclocarbonate of bisphenol A (BisA-5dCC) was prepared from a BisA tetraol. H 2 N-terminated PHUs were synthesized further from the aminolysis of BisA-5dCC. Hybrid non-isocyanate polyurethanes (HNIPUs) were obtained from PHUs and epoxys. HNIPUs prepared from aromatic epoxy showed high T g up to 81°C. They showed excellent tensile strength as high as 60 MPa.
研究领域:
材料科学
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化学工程
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DOI
高影响因子
Nanoscale
·
2024
·Vol. 16
·期 46
·21594-21603
·
IF 5.8
Yuliang Guo,Wenshu Tai,Mingyu Zhao,Xiao Chen,Yuchao Chai,Guangjun Wu,Landong Li
Self-pillared pentasil (SPP) zeolites have received considerable interest due to their distinctive intergrowth structure, while the precise process and mechanism for the formation of SPP zeolites remain obscure. Herein, SPP zeolites (ZSM-5) have been successfully synthesized by pre-aging an Al-rich gel without employing any organic templates or seeds for the first time. The as-synthesized SPP zeolites possess a notably high external surface area while the micropores for Ar adsorption are partially blocked by excess Na+, which can be fully recovered by Mg2+ or H+ exchange. The crystallization process is monitored and the impacts of synthesis parameters are investigated. The results show that self-pillaring originates from the partial lattice distortion at the intersections of nanosheets, offering a new insight into the self-pillaring process. Typically, with decreasing SiO2/Al2O3 ratio, more crossovers could be observed in the crystals, hinting that self-pillaring predominately occurs at the (101) plane of twins in the ZSM-5 precursor due to Al-rich lattice distortion. Finally, in the catalytic cracking of n-heptane, H-SPP zeolites exhibit superior performance to commercial H-ZSM-5 zeolites due to their abundant Brønsted acid sites arising from a low framework SiO2/Al2O3 ratio of ∼21 and the short diffusion path originating from the house-of-cards structure.
研究领域:
材料科学
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化学工程
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产品关联
DOI
PubMed
高影响因子
Journal of Energy Chemistry
·
2025
·
IF 14.9
Fengli Yuan,Wenhui Li,Hong Yang,Guangjin Hou,Kuizhi Chen,Junhui Yu,Min Liu,Xinwen Guo
Carbon dioxide hydrogenation to gasoline can effectively alleviate the energy crisis and benefit the global environment. Owing to its orthogonally connected nanosheet configuration, large pore volume, and appropriate thickness of single nanosheet, self-pillared pentasil (SPP) nanosheet zeolite is integrated with In 2 O 3 -ZrO 2 as a tandem catalyst for CO 2 hydrogenation to C 5+ hydrocarbons. By substituting Al in the SPP framework with Ga, the acid strength of SPP is reduced, and acid density is increased, which favors the generation of C 5+ hydrocarbons and enhances the cracking resistance of long-chain hydrocarbons. A maximum C 5+ hydrocarbon selectivity of 82% was obtained on In 2 O 3 -ZrO 2 /Ga-SPP (Si/Ga=100), which shows no deactivation after 200 h reaction time. Furthermore, introducing Pd into the In 2 O 3 -ZrO 2 not only boosts CO 2 conversion to 11% but also suppresses methane selectivity to below 1%. This study offers valuable insights into the design of highly active CO 2 -to-gasoline catalysts by leveraging the distinctive structure and acidity of zeolites within the tandem catalyst systems.
研究领域:
催化化学
·
能源化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
TETRAHEDRON
·
2013
·
IF 2.803
Kun Tong,Jinchang Tu,Xueyong Qi,Min Wang,Yanjie Wang,Haizhen Fu,Charles U. Pittman,Aihua Zhou
Five- and seven-membered sultam derivatives were conveniently synthesized via intra- or intermolecular Michael additions and an improved vinyl sulfonamide Baylis–Hillman reaction. Two different cyclization pathways were explored for the oxa-Michael reaction. A good solvent was discovered for an otherwise sluggish ketone-type Baylis–Hillman reaction in which vinyl sulfonamide ketones were used as the precursors. Furthermore, a strong base caused vinyl sulfonamide ketones to undergo 5- endo - trig intramolecular cyclizations, which are disfavored according to Baldwin's rule. Finally Baylis–Hillman reaction products were used as scaffolds for diversity-oriented sultam syntheses.
研究领域:
有机化学
·
合成化学
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产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2025
·
IF 13.2
Zijun Huang,Xiaohua Cao,Hao Wang,Dingkai Chen,Xianming Chen,Dedong He,Shuquan Huang,Yongming Luo
Propane dehydrogenation (PDH) is a potential secure technique for manufacturing propylene. Transition-metal-based catalysts for propane dehydrogenation reaction, particularly Co 2+ , have been developed rapidly over the past few years. However, determining the interaction between Co 2+ species and zeolites has proven to be a formidable challenge in achieving the controllable construction of Co species as active sites for dehydrogenation. In this study, we synthesized a nickel–cobalt catalyst supported on self-pillared pentasil zeolite (CoNi@SPP) with a moderate metal oxide-support interaction for the PDH reaction. Specifically, the interaction is achieved by the electron transfer between nickel and cobalt, which subsequently reduces the strength of the Co 2+ interaction with the silicon support. Further insights provided by pyridine IR spectra and NH 3 -TPD emphasize that such moderate interaction results in an increased number of Lewis acid sites, ultimately intensifying the PDH produce propylene and H 2 . The detailed study of catalyst’s properties provides new inspirations into utilizing additive to optimize metal oxide-support interactions, thus facilitating the development of highly active cobalt-based catalysts for propane dehydrogenation.
研究领域:
催化化学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
Analytical Methods
·
2020
·Vol. 13
·期 5
·620-625
·
IF 2.596
Chan Wang,Longbin Qi,Rongning Liang
Polymeric membrane potentiometric sensors based on molecularly imprinted polymers (MIPs) have been successfully designed for the detection of organic compounds both in ionic and neutral forms. However, most of these sensors are based on the non-covalent recognition interactions between the functional groups of the MIP in the polymeric sensing membrane and the target. These weak non-covalent interactions are unfavorable for the detection of hydrophilic organic compounds (e.g., dopamine). Herein novel MIP potentiometric sensor based covalent recognition for the determination of protonated dopamine is described. Uniform-sized boronate-based MIP beads are utilized as the recognition receptors. These receptors can covalently bind with dopamine with a cis-diol group to form a five-membered cyclic ester and thus provide a higher affinity because of the stronger nature of the covalent bonds. It has been found that the proposed electrode shows an excellent sensitivity towards dopamine with a detection limit of 2.1 μM, which could satisfy the needs for in vivo analysis of dopamine in the brain of living animals. We believe that the covalent recognition MIP-based sensing strategy provides an appealing way to design MIP-based electrochemical and optical sensors with excellent sensing properties.
研究领域:
分析化学
·
生物传感器
·
材料科学
·
神经科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF CLUSTER SCIENCE
·
2017
·Vol. 28
·期 6
·3059-3066
·
IF 1.471
Liang Hua,Yang Zhen-Yuan,Yan Min-Hao,Xie Su-Yuan
The fullerenes that violate isolated pentagon rule (IPR) have unusual electronic properties resulting from their fused-pentagon structures. Numerous non-IPR fullerenes have now been captured by chlorination, affording opportunity to go insight into the properties involved in non-IPR fullerenes in the forms of chlorofullerenes (CFs). Here cyclic voltammetry (CV) is employed to probe the electrochemical properties of non-IPR #1809 C 60 Cl 8 in comparison with those of #271 C 50 Cl 10 . Differing from IPR-satisfying CFs such as C 60 Cl 8 and C 60 Cl 10 (referring to I
h -symmetric C 60 ), the two non-IPR CFs exhibit divergent electroactive polymerization characters. In addition, the electrocatalytic effect of ferrocene that is otherwise employed as internal reference has been shown in the CV process of CFs.
研究领域:
材料化学
·
物理化学
·
纳米材料
·
电化学
·
富勒烯化学
✓ 已验证
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2024
·
IF 8.1
Qiyu Meng,Yupei Wang,Meng Rong,Huifang Xing,Liangrong Yang,Huizhou Liu,Ru-An Chi,Congmei Chen
The separation of 1,2,4-butanetriol (BT) through phenylboronate anion reactive extraction in fermentation broth has been proposed based on the process where the boronic acid groups specifically recognize the cis -dihydroxyl groups. To fully elucidate the affinity process of boronic acid group and polyols, here we have investigated the binding constant ( K a ) and thermodynamic data of four phenylboronic acid derivates (PBADs) and four structurally similar linear polyols (BT, 1,2-butanediol (1,2-BD), 1,3-butanediol (1,3-BD), and 1,4-butanediol (1,4-BD)) through fluorescence spectroscopy, isothermal titration calorimetry (ITC), and computational chemistry. It can be concluded that the substituent group of boronic acid, the numbers and relative positions of the hydroxyl group in polyols affected the affinity of the boronic acid group to it. The ionized boronic acid group preferentially reacts with the 1,2-dihydroxy group to form a pentacyclic phenylboronate. Compared with other three butanediols, phenylboronic acid (PBA) has a larger binding constant and shows a smaller Gibbs free energy change with BT.
研究领域:
化学
·
材料科学
·
分析化学
·
物理化学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）