DALTON TRANSACTIONS
·
2024
·
IF 3.5
Peiyao Liu,Zhengzeng Yang,Mengyuan Zhang,Yufeng Liu,Dandan Han,Dan Wu,Charles Chunbao Xu,Jianshe Wang
C-H carboxylation of furoic acid (FA) with CO2 is an atom-efficient strategy to produce 2,5-furandicarboxylic acid (2,5-FDCA) from lignocellulose. The existing carbonate-promoted CO2 carboxylation processes rely on the use of large amounts of expensive Cs2CO3 as deprotonating reagent and molten salt. Substitution of Cs with other cheap and abundant alkali ions (such as K and Na) can reduce the use of Cs, but faces the problem of low yield of 2,5-FDCA. This study found that the addition of catalytic amounts of ZnCl2 as a Lewis acid can increase the yield of 2,5-FDCA in the CO2 carboxylation reaction of Na/K-FA in a molten salt reaction system. 1H NMR analysis and DFT calculations confirmed that ZnCl2 coordinates with the furan ring through electron transfer from the conjugated furan ring to Zn2+, thereby activating the H at the C5 position of Na/K-FA. This coordination lengthened the C5-H bond and lowered its heterolytic dissociation energy, making it more susceptible to being deprotonated by CO32- and subsequently carboxylated by CO2. The developed Lewis acid coordination strategy provides a new idea for the efficient construction of C-C bonds between CO2 and aromatics through carbonate-promoted C-H carboxylation.
研究领域:
化学工程
·
可再生资源转化
·
催化化学
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF ANALYTICAL AND APPLIED PYROLYSIS
·
2025
·
IF 6.2
Yilun Liang,Mo Yang,Wenjun Wu,Xinzhe Zhang,Juan Wang
2,2,4,6,6-Pentamethylheptane (iso-dodecane) is the primary component of alcohol-to-jet synthetic paraffinic kerosene and also plays a crucial role as an iso-alkane component in jet fuel surrogates. However, there is limited availability of pyrolysis studies on iso-dodecane and its kinetic model requires improvement. In this study, the pyrolysis and oxidation experiments of iso-dodecane were conducted using a flow reactor combined with on-line gas chromatographic (GC) and GC - mass spectrometry (MS) to obtain the mole fraction profiles of species. Based on the obtained experimental data, a new kinetic model for iso-dodecane was developed and validated, demonstrating superior predictive performance compared to the literature models. The rate of production analysis and sensitivity analysis were performed to elucidate the high temperature reaction mechanisms of iso-dodecane. The primary decomposition of iso-dodecane in pyrolysis occurs through unimolecular decomposition channel (U-D) and H-abstraction channel (H-A). The U-D reaction XC 12 H 26 = TC 4 H 9 + IC8–5R governs the fuel's reactivity in pyrolysis. Furthermore, a pyrolysis experiment was conducted for n-dodecane under identical conditions to those employed for iso-dodecane pyrolysis, allowing for a comparison between the two fuels based on the experimental data and modeling analysis. Iso-dodecane exhibits higher pyrolysis reactivity than n-dodecane due to its stronger ability in U-D. The new model was also validated by the ignition delay times from the literature.
研究领域:
化学工程
·
燃料科学
·
燃烧动力学
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产品关联
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2022
·
IF 10.53
Qinsheng Wang,Yiyi Fan,Chengliang Wu,Yun Jin,Claudia Li,Jaka Sunarso,Xiuxia Meng,Naitao Yang
Research on gas separation membrane has targeted upon maximizing the selectivity and permeance. The development of 2D materials ( e.g. , MXene) gives a novel avenue to surpass the “trade-off” among the membrane selectivity and permeability. However, randomly stacked nanosheets and the regulation of interlayer spacing for MXene nanosheets hinder the development of MXene membrane. To this end, we designed a Pd-intercalated lamellar MXene membrane to modify the surface chemical properties (H-spillover effect) of MXene (Ti 3 C 2 T x ) and to expand the interlayer spacing (from 2.29 to 3.26 Å) due to the strong interaction between Pd 2+ and MXene nanosheets with negative charge. Here, we performed a single-step etching approach to prepare 2D Pd-MXene membrane and demonstrated its excellent H 2 permeability of 2.66 × 10 −7 mol m −2 s −1 ·Pa −1 and H 2 /CO 2 selectivity of 242 at 25 °C, which greatly exceeds the current benchmark membranes. We also developed single gas transport mathematical mechanism models to interpret and support the experimental results. The combined experimental and modeling results show that interlayer spacing and H-spillover effect of Pd-MXene membrane benefit H 2 /CO 2 separation.
研究领域:
材料科学
·
化学工程
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DOI
高影响因子
JOURNAL OF ORGANIC CHEMISTRY
·
2020
·
IF 4.335
Wubing Yao,Jiali Wang,Lili He,Dongdong Cao,Jianguo Yang
A ruthenium catalytic ortho-C–H diborylation of 2-arylpyridine derivatives, including challenging 2-phenoxypyridine functions, using a remarkably low catalyst loading and a low-cost and bench-stable boron source, has been developed. The novel strategy shows high activity with excellent selectivity and may offer a versatile and green alternative to currently employed high loadings of noble metals or extra additives for the selective borylations.
研究领域:
有机化学
·
催化化学
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DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
·
2022
·
IF 24.319
Yalin Yang,Zheyan Chen,Hanlin Huang,Yuxin Liu,Junhua Zou,Shuqi Shen,Jiawei Yan,Jinshui Zhang,Zanyong Zhuang,Zhongzhen Luo,Chengkai Yang,Yan Yu,Zhigang Zou
Halide perovskites and derivatives have been used as emerging photocatalysts due to their unique optoelectronic and structural diversity. However, compared with the well-explored photophysical processes for light-driven more energetic carriers to trigger redox reactions, catalytic effects on the surface of halide perovskite or their derivatives for chemical transformations between reactive species are seldom addressed, which is equally important for improving the efficiency for halide perovskite-based photocatalysts. Here, we demonstrate that Cs 3 Bi 2 Br 9 sites in the Cs 3 Bi 2 Br 9 /CdS heterojunction, not only participate in light-driven processes, but also play a vital role for the activation and conversion of key intermediates during C(sp 3 )-H bond transformation, via a more thermodynamically and kinetically favorable surface reaction pathway. Besides, various aromatic hydrocarbons can be effectively photocatalytic converted to corresponding aldehydes/ketones as major products. This work highlights the importance of surface catalysis mechanism in photocatalysis not only for halide perovskites but also for other semiconductors.
研究领域:
材料科学
·
化学工程
·
光化学
✓ 已验证
DOI
高影响因子
CEMENT AND CONCRETE RESEARCH
·
2025
·
IF 13.1
Hui Xie,Xin Liu,Haochuan Wang,Zhenqi Yu,Lijing Shao,Wei Wang,Jinxiang Hong,Chong Wang,Pan Feng
The use of aluminum sulfate (Al 2 (SO 4 ) 3 )-based alkali-free accelerators in shotcrete often impeded tricalcium silicate (C 3 S) hydration, leading to poor ultra-early strength development. To address this, a novel stage-wise kinetic control strategy was proposed to regulate the sequential formation of ettringite and C-S-H gel through the delayed addition of C-S-H nano seeds. The dosage of C-S-H nano seeds, delayed time, addition sequence of Al 2 (SO 4 ) 3 and C-S-H nano seeds were carefully examined in this study, and the effects of addition sequence on the hydration kinetic, hydration products, and pore structure of cement pastes were systematically investigated. Results demonstrated a significant enhancement in 6 h compressive strength, achieving a 35% increase when C-S-H nano seeds (4% dosage) were added 1 h after initial mixing compared to simultaneous addition. Hydration heat, XRD, TG, SEM, and BSE-EDS analyses revealed that the delayed addition promoted C 3 S hydration at later stages by staggering intensive ettringite formation and C-S-H gel precipitation, mitigating competition for calcium ions. This stage-wise approach facilitated C-S-H gel integration into the pre-constructed porous ettringite skeleton, refining the pore structure and enhancing ultra-early mechanical performance. These findings highlight an effective strategy to optimize hydration kinetics and strength development in shotcrete applications.
研究领域:
土木工程
·
材料科学
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产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2025
·
IF 13.2
Zhikang Xu,Yunxing Zhang,Xing Wu,Haibo Zhu
Co-based catalysts are emerging as one of the most promising catalysts for propane dehydrogenation (PDH) due to their abundant availability, environmental friendliness, and efficient activation of the C–H bond. Isolated Co(II) is recognized as the active site for activating the C–H bond in PDH; however, the controllable synthesis of Co catalysts with well-defined isolated Co(II) remains a challenge. In this study, a direct and straightforward route was developed for the synthesis of Co-Beta using a fluorine-assisted hydrothermal crystallization method. The structure of Co-Beta was studied using various characterization tools, including XRD, STEM, H 2 -TPR, UV–vis, XPS, solid-state 29 Si MAS NMR and EXAFS techniques. It was confirmed that the Co species are incorporated into the structure of Beta zeolite, existing as isolated Co(II) sites embedded within the framework of Beta zeolite. The optimized catalyst, 1.0Co-Beta, exhibits excellent performance in PDH, achieving a propane conversion of approximately 50 % and propylene selectivity of around 96 % at 600 °C. This performance surpasses that of previously reported non-noble metal catalysts. This study provides fundamental insights on the design and synthesis of highly dispersed metal oxide catalysts for PDH.
研究领域:
催化化学
·
材料科学
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产品关联
DOI
高影响因子
RSC Advances
·
2016
·Vol. 6
·期 59
·54377-54381
·
IF 3.289
Dingyi Wang,Shengmei Guo,Rongxing Zhang,Sen Lin,Zhaohua Yan
An efficient procedure for the formation of C–S bonds via C–H functionalization was developed for the synthesis of aryl sulfides in good to excellent yields using TBAI–HBr system promoted direct sulfenylation of various compounds, such as phenols, pyrazolones, indoles and related heteroarenes. Low cost and widely available arylsulfonyl chlorides were used as the sulfur source to provide various sulfur-containing compounds. The characteristic of the present protocol is convenient, green, highly efficient with a wide-application and short reaction time.
研究领域:
有机化学
·
合成化学
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DOI
高影响因子
Foods
·
2024
·Vol. 13
·期 17
·2652
·
IF 4.7
Na Li,Xiao Wu,Qin Yin,Zeng Dong,Lele Zheng,Yihui Qian,Yulu Sun,Ziping Chen,Kefeng Zhai
The extraction of total flavonoids fromHylotelephium spectabile(Boreau) H. Ohba (H. spectabile) leaves was studied through the use of a double enzyme-assisted ultrasonic method, and the extraction process was optimized using the Box–Behnken design. Eight different macroporous resins were screened for purification in single-factorial experiments, and the flavonoid compounds in the extract ofH. spectabileleaves were identified using HPLC-MS. Through the evaluation of the total reducing capacity and capacity for reducing 1,1-diphenyl-2-trinitrophenylhydrazine (DPPH), hydroxyl radicals (·OH), and 2,2’-biazobis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt (ABTS), the in vitro antioxidant activities of the crude extracts of the total flavonoids and purified total flavonoids ofH. spectabileleaves were investigated. The results showed that the most efficient conditions for flavonoid extraction were an ultrasonic extraction time of 60 min, an ethanol concentration of 35%, a liquid-to-material ratio of 20:1 mL/g, and an amount of enzyme (cellulose/pectinase = 1:1) of 1.5%, formingH. spectabilepowder. Under these conditions, the total flavonoid extraction rate in theH. spectabileleaf extract was 4.22%. AB-8 resin showed superior performance in terms of purification, and the optimal adsorption and desorption times were 1.5 h and 3 h, respectively. The recommended parameters for purification included a liquid volume of 5.5 BV, a flow rate of 1.2 BV/min, a pH of 5, and a concentration of 0.8 mg/mL. The observed order for reducing capacity was ascorbic acid (VC) > rutin > purified total flavonoids > crude extract of total flavonoids. The purified total flavonoid extract fromH. spectabileshowed a good scavenging ability against DPPH, ·OH, and ABTS·+, suggesting strong antioxidant activity. Therefore, this study can serve as technical support and reference data for the further development and utilization ofH. spectabileresources.
研究领域:
植物化学
·
分析化学
·
生药学
·
生物技术
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产品关联
DOI
PubMed
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2025
·
IF 6.3
Lu Wen,Chaojie Li,Houqun Xiao,Huazhou Hu,Chaobin Lai,Luocai Yi,Qingjun Chen
The ZrCo alloy stands out as one of the most promising candidates for hydrogen isotope storage materials in nuclear fusion, owing to its extremely low equilibrium hydrogen pressure (10 −3 Pa, 20 ℃). However, ZrCo experiences severe disproportionation reactions during dehydrogenation/hydrogenation processes, which lead to significant performance degradation. To address this, we have introduced V and Ti into the ZrCo alloy, resulting in the Zr 0.8 V x Ti 0.2-x Co (x = 0–0.15) series. Our research indicates that the addition of V and Ti reduces the lattice parameters, thereby increasing the platform pressure for hydrogen desorption and decreasing the enthalpy and entropy of the desorption reaction. This modification allows for a lower desorption temperature and enhances the alloy's resistance to hydrogen-induced degradation. Remarkably, the hydrogen storage capacity of the Zr 0.8 V x Ti 0.2-x Co(x = 0–0.15) alloys remains stable after 19 h of desorption. Furthermore, the Zr 0.8 V 0.05 Ti 0.15 Co alloy demonstrates exceptional cycling stability, retaining over 99 % of its hydrogen storage capacity after 50 cycles. First-principles calculations have clarified the adsorption energies of hydrogen at different binding sites, revealing the following order of stability: E b(Ti-V) < E b(Zr-Ti) < E b(V-Zr) < E b(Zr-Zr) . The hydrogen absorption and desorption kinetics of the Zr 0.8 V x Ti 0.2-x Co alloys follow the trend: Zr 0.8 V 0.15 Ti 0.05 Co > Zr 0.8 V 0.1 Ti 0.1 Co > Zr 0.8 V 0.05 Ti 0.15 Co > ZrCo, indicating optimized performance with the introduction of V and Ti. This study not only provides a viable solution to the disproportionation issue in ZrCo alloys but also offers valuable insights into the design of high-performance hydrogen isotope storage materials for nuclear fusion applications.
研究领域:
材料科学
·
核聚变工程
·
金属氢化物
·
储氢材料
·
物理化学
·
计算材料学
✓ 已验证
产品关联
DOI
高影响因子
Chemical Science
·
2025
·
IF 7.4
Guozhou Feng,Yuxin Fan,Lechen Diao,Zhichao Miao,Jin Zhou
Electrocatalytic hydrogenation (ECH) of 5-hydroxymethylfurfural (HMF) to 2,5-bis(hydroxymethyl)furan (BHMF) is regarded as a green synthesis strategy for generating high quality bio-based chemicals. However, simultaneously regulating both the hydrogen (H) coverage and the adsorption behavior of HMF presents a significant challenge, particularly in unraveling the intricate structure–activity relationship and achieving a selective target product. Here, we enhance the availability of hydrogen (H*) and modulate surface electronic interactions with 5-hydroxymethylfurfural (HMF) to facilitate selective electrochemical hydrogenation (ECH) of HMF by introducing palladium as an auxiliary component. Pd–Cu dual sites synergistically enhanced H* supply and HMF activation while suppressing the competing hydrogen evolution reaction. The optimized electrocatalyst exhibits notable catalytic performance, attaining a selectivity of 99.3% and a faradaic efficiency of 97.5% for BHMF at a potential of −1.15 V (vs. Ag/AgCl). Density functional theory (DFT) calculations demonstrate that Pd doping is crucial for enhancing the adsorption of H* and HMF* intermediates, thereby promoting the hydrogenation of HMF through the Langmuir–Hinshelwood (L–H) mechanism under neutral conditions. This work establishes a catalyst design paradigm where atomic-level dopant engineering regulates multistep protonation kinetics, offering fundamental insights into biomass electrorefining.
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产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING SCIENCE
·
2025
·
IF 4.3
Qian Wang,Bohui Xu,Lingyao Kuang,Jie Zhang,Zheshuai Lin,Hanyu Xu,Xiaolei Ren,Tiefeng Liu,Xingxing Gu
Aqueous zinc metal batteries (AZMBs) are promising for next-generation storage due to safety, low cost, and eco-friendliness, but suffer from Zn dendrites and hydrogen evolution. Here, a gradient zincophilic-hydrophobic (GF@PFA) separator is fabricated via capillary adsorption and in-situ polymerization. Its top retains GF hydrophilicity for electrolyte wetting, while the polyfurfuryl alcohol (PFA) coating at the bottom, rich in C-O groups, guides uniform Zn 2+ deposition. Simultaneously, the hydrophobic framework blocks H 2 O contact with the Zn anode, impeding H + migration. This decouples Zn 2+ /H + transport paths, optimizing ion dynamics and interface stability. Therefore, the Zn||Zn symmetrical battery achieved an 1800 h cycle at 2 mA cm −2 /2 mAh cm −2 , which was more than 8 times higher than that of the original GF. The Zn||ZnS full cell delivers 633.5 mAh g −1 and 99.7 % CE at 0.5 A g −1 , retaining 81 % capacity after 1350 cycles. This work confirms that the design of gradient functionalized separators can collaboratively solve the multi-scale interface imbalance problem of zinc anodes, providing an innovative strategy and theoretical basis for the development of long-life AZMBs.
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）