CRYSTENGCOMM
·
2022
·Vol. 24
·期 46
·8060-8069
·
IF 3.756
Shu-Qin Qin,Wei Xu,Wen-Cai Ye,Ren-Wang Jiang
Guanidinium–naphthalenedisulfonic acid (GNPS) was used as a molecular catcher because (i) it contains a cavity and channel in the network; (ii) NH2+ can be used as a hydrogen bond donor, and SO3− can be used as a hydrogen bond acceptor; (iii) the co-planar naphthalene rings can form aromatic interactions with guest molecules. The liquid guests 1–8 [(−)-isopulegol (1), (−)-menthyl acetate (2), isoeugenol (3), 2,6-dimethylaniline (4), methyleugenol (5), 2,6-diisopropylaniline (6), methyl salicylate (7) and L(−)-carvone (8)] are successfully encapsulated in the cavity of GNPS and eight new crystals were obtained. Both aromatic and non-aromatic molecules form hydrogen bonds and C–H⋯π interactions with GNPS. Co-crystallization of 1–4 with GNPS led to stronger C–H⋯π interactions as compared to the previously reported GBPS. Furthermore, compounds 5–8 which were not co-crystallized with GBPS were found to be encapsulated in the cavity of GNPS. We found that the aromatic cavity of GNPS with hydrogen bonding and enhanced C–H⋯π interactions can be regarded as a useful tool for the structural determination of liquid molecules. Furthermore, the correct absolute configurations of 1, 2 and 8 can be assigned based on the small Flack parameters because of the presence of sulfur atoms in the host molecule GNPS.
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DOI
高影响因子
Frontiers of Chemical Science and Engineering
·
2024
·Vol. 18
·期 5
·1-9
·
IF 4.3
Gu Jianxia,Zhu Ying,Zheng Haiyan,Sun Chunyi,Su Zhongmin
A novel, cheap and highly efficient Ni-Co/Mo 2 C/Co 6 Mo 6 C 2 @C nanocomposite has been successfully constructed through simple one-step carbonization method in a nitrogen atmosphere. Polyethyleneimine in the precursor can effectively anchor molybdenum-based Keggin-type polyoxometallate and NiCo-layered double hydroxide through electrostatic and coordination interactions, which avoids the aggregation of catalyst particles during the pyrolysis process. After optimization, the obtained Ni-Co/Mo 2 C/Co 6 Mo 6 C 2 @C possesses small size (3–8 nm), large specific surface area and hierarchical pore structure. More importantly, Ni-Co/Mo 2 C/Co 6 Mo 6 C 2 @C presents remarkable hydrogen evolution reaction activity with low overpotentials in 0.5 mol·L −1 H 2 SO 4 (102.3 mV) and 1 mol·L −1 KOH (95 mV) to afford the current density of 10 mA·cm −2 , as well as small Tafel slopes of 82.49 and 99.92 mV·dec −1 , respectively. Simultaneously, this catalyst also shows outstanding stability for 12 h without a significant change in current density. The excellent catalytic performance of Ni-Co/Mo 2 C/Co 6 Mo 6 C 2 @C can put down to the synergistic effect between multiple components and the small size of the catalyst. This work provides unique insights into the preparation of efficient transition metal-based catalysts for HER.
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DOI
高影响因子
MATERIALS LETTERS
·
2022
·
IF 3.574
Feifei Zhou,Ganghua Pan,Haining Meng,Hailong Sun
For preparing finer and well-dispersed calcium-silicate-hydrate (C-S-H) seeds at a lower cost, the waste solution of acid treatment of recycled concrete aggregates (RCAs) and black liquor from pulping were used for the synthesis of C-S-H seeds. The results show that C-S-H seeds can be successfully fabricated by chemical co-precipitation reaction using the two waste solutions. Interestingly, it was globular rather than traditional foil-like. Furthermore, C-S-H seeds synthesized using the two waste solutions had smaller particle size and better dispersibility. More importantly, it had a more prominent accelerating effect to the strength development of mortar, significantly enhancing the early and long-term compressive strength of mortar.
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DOI
高影响因子
ANTICANCER RESEARCH
·
2024
·Vol. 44
·期 7
·2861-2870
·
IF 1.6
YINA ZHANG,XIAOCEN NIU,YUANHE WANG,SHUTING BAO,PEIYUE JIANG,XIAORUI DONG
Background/Aim: Glutamine metabolism is crucial in cell proliferation, aging, and apoptosis across various cancer types. Existing research indicates that Sirtuin 4 (SIRT4), primarily located in mitochondria, modulates this process. This study aimed to clarify the regulatory relationship between SIRT4 and glutamine metabolism in cervical cancer. Materials and Methods: SIRT4 mRNA levels and their clinical correlation to cervical cancer were analyzed using the UALCAN database. Immunohistochemistry (IHC) was performed to assess SIRT4 protein expression in tissue samples from cervical cancer patients. Transient transfection was employed to create Hela and Siha cell lines with overexpressed SIRT4, mitogen-activated extracellular signal-regulated kinase (MEK), and glutaminase 1 (GLS1). The impact on cellular functions was studied using MTT, soft agar, transwell, and western blotting assays. Glutamate and ATP levels were also measured to evaluate metabolic changes. Results: Low levels of SIRT4 mRNA in cervical cancer tissues correlated with tumor metastasis and poor survival rates. Overexpression of SIRT4 led to suppressed cell proliferation, colony growth, and motility, along with significant down-regulation of GLS expression, a key contributor to glutamine metabolism. Additionally, SIRT4 overexpression resulted in the inactivation of the MEK/ERK/c-myc signaling pathway, while overexpression of MEK reversed these effects. Notably, the inhibitory effects of SIRT4 on cell proliferation, colony formation, migration, and invasion in Hela and Siha cells were significantly attenuated following GLS1 overexpression. Conclusion: SIRT4 acts as an anti-cancer agent in cervical cancer by inhibiting glutamine metabolism through the MEK/ERK/c-myc signaling pathway, providing a novel sight for cervical cancer therapy.
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DOI
PubMed
高影响因子
ChemSusChem
·
2020
·Vol. 13
·期 18
·4922-4928
·
IF 7.962
Zihao Zhang,Wenwen Lin,Yafei Li,Francis Okejiri,Yubing Lu,Jixing Liu,Hao Chen,Xiuyang Lu,Jie Fu
Graphical Bimetallic boost : A NiFe/C bimetallic catalyst is reported, composed of NiFe alloy in the material bulk and a surface mixture of NiFe alloy and oxidized NiFe δ + species, exhibiting a heptadecene yield of 70.1 % with selectivity to 1-heptadecene as high as 92.8 % at just 190 °C. Catalytic deoxygenation of even-numbered fatty acids into odd-chain linear α-olefins (LAOs) has emerged as a complementary strategy to oligomerization of ethylene, which only affords even-chain LAOs. Although enzymes and homogeneous catalysts have shown promising potential for this application, industrial production of LAOs through these catalytic systems is still very difficult to accomplish to date. A recent breakthrough involves the use of an expensive noble-metal catalyst, Pd/C, through a phosphine ligands-assisted method for LAOs production from fatty acid conversion. This study presents a unique, cost-friendly, non-noble bimetallic NiFe/C catalyst for highly selective LAOs production from fatty acids through decarbonylative dehydration. In the presence of acetic anhydride and phosphine ligand, a remarkable improvement in the yield of 1-heptadecene from the conversion of stearic acid was found over the supported bimetallic catalyst (NiFe/C) as compared to corresponding monometallic counterparts (Ni/C and Fe/C). Through optimization of the reaction conditions, a 70.1 % heptadecene yield with selectivity to 1-heptadecene as high as 92.8 % could be achieved over the bimetallic catalyst at just 190 °C. This unique bimetallic NiFe/C catalyst is composed of NiFe alloy in the material bulk phase and a surface mixture of NiFe alloy and oxidized NiFe δ+ species, which offer a synergized contribution towards decarbonylative dehydration of stearic acid for 1-heptadecene production.
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DOI
高影响因子
ACS Applied Materials & Interfaces
·
2019
·
IF 8.456
Lin Li,Shuiyun Shen,Guanghua Wei,Xiaolin Li,Kun Yang,Qi Feng,Junliang Zhang
There remain great challenges in exploring cost-effective and highly efficient non-noble metal electrocatalysts to catalyze the oxygen reduction reaction (ORR) of proton exchange membrane fuel cells (PEMFCs). Also, a further validation on their performances under a fuel cell operating condition draws sustained attention. Herein, we report a comprehensive investigation on the ORR performances of a series of pyrolyzed Fe–N–C composites that use phenanthrolene as the nitrogen precursor, and the effects of carbon supports, transition metal precursors, and annealing temperatures are examined in detail. Electrochemical measurements combined with different physicochemical characterizations are employed to clarify the function of critical structures including the specific surface area, microstructure, nitrogen content, nitrogen type, and corresponding proportion on their ORR and fuel cell performances. It demonstrates a half-wave potential of 0.79 V and almost a four-electron pathway. When using the as-optimized Fe–N–C composite as the cathode catalyst of a PEMFC, the maximum power density reaches as high as 540 mW cm–2.
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DOI
高影响因子
Frontiers of Chemical Science and Engineering
·
2024
·Vol. 18
·期 10
·1-10
·
IF 4.3
Jia Hongwei,Yue Xiaoyang,Hou Yuying,Huang Fei,Cao Cuiyao,Jia Feifei,Liu Guanhua,Zheng Xiaobing,Liu Yunting,Jiang Yanjun
Unspecific peroxygenases exhibit high activity for the selective oxyfunctionalization of inert C(sp 3 )-H bonds using only H 2 O 2 as a clean oxidant, while also exhibiting sensitivity to H 2 O 2 concentration. CdS-based semiconductors are promising for the photosynthesis of H 2 O 2 owing to their adequately negative potential for oxygen reduction reaction via a proton-coupled electron transfer process, however, they suffer from fast H 2 O 2 decomposition on the surface of pristine CdS. Therefore, [Cp*Rh(bpy)H 2 O] 2+ , a highly selective proton-coupled electron transfer catalyst, was anchored onto a supramolecular polymer-grafted CdS nanoflower to construct an efficient integrated photocatalyst for generating H 2 O 2 , mitigating the surface issue of pristine CdS, increasing light absorption, accelerating photonic carrier separation, and enhancing oxygen reduction reaction selectivity to H 2 O 2 . This photocatalyst promoted the light driven H 2 O 2 generation rate up to 1345 µmol·L −1 ·g −1 ·h −1 , which was 2.4 times that of pristine CdS. The constructed heterojunction photocatalyst could supply H 2 O 2 in situ for nonspecific peroxygenases to catalyze the C-H oxyfunctionalization of ethylbenzene, achieving a yield of 81% and an ee value of 99% under optimum conditions. A wide range of substrates were converted to the corresponding chiral alcohols using this photo-enzyme catalytic system, achieving the corresponding chiral alcohols in good yield (51%–88%) and excellent enantioselectivity (90%–99% ee).
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DOI
高影响因子
IONICS
·
2021
·Vol. 27
·期 9
·3761-3768
·
IF 2.817
Li Wei,Ai Huiting,Liu Zheng,Wei Chuchu,Han Guo-Cheng,Zhan Ling
In order to improve the electrochemical properties of Na 2 MnPO 4 F (NMPF), low-cost biomass cane bagasse was used as a carbon source for coating, Na 3 V 2 (PO 4 ) 2 F 3 (NVPF) was used as a doped phase to prepare different ratios of xNa 3 V 2 (PO 4 ) 2 F 3 ·(1-x)Na 2 MnPO 4 F@C (NVPF/NMPF@C) composite materials via a sol–gel method. The results including analysis of XRD, SEM, EDS, and XPS methods showed that NVPF/NMPF@C (x = 0.2) composite material had good crystallinity, and NVPF can be uniformly doped in NMPF@C. The rate performance of NVPF/NMPF@C composite was tested at 0.1, 0.2, 0.5, 1, and 2 C. The first discharge specific capacity of NVPF/NMPF@C composite electrode material reached 193 mAh/g and increased by approximately 20 times when compared to only 9 mAh/g of NMPF@C. The coulombic efficiency of NVPF/NMPF@C material remained 95% after 35 cycles at 0.1 C. The introduction of NVPF can improve charge transfer and Li + diffusion, and enhance the electrochemical behavior of the lithium-ion battery cathodes.
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DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
·
2018
·
IF 11.698
Jingyu Wang,Min Xu,Jianquan Zhao,Huaifang Fang,Qingzhu Huang,Weiping Xiao,Tao Li,Deli Wang
The activity and stability of Pt electrocatalysts are crucial issues for energy conversion systems involving oxygen reduction reaction (ORR). In this work, the ultrafine Pt nanoparticles were in situ reduced by the photogenerated electrons on TiO 2 surface so that most of them selectively anchored around the TiO 2 nanocrystals. The presence of well-dispersed TiO 2 on carbon surface strengthened the metal-support interaction, giving rise to the improved ORR catalytic activity with ∼49 mV positive shift of half-wave potential as compared to commercial 20 wt% Pt/C. More importantly, the Pt/TiO 2 -C catalysts exhibited a more durable performance after 10,000 cycles in terms of the decrease in electrochemical surface area (0.8%) and mass activity (0.9%), much lower than those of Pt/C (10.2% and 33.3%). The high-temperature durability test also revealed a much higher retention of ORR activity. The results demonstrated that anchoring Pt on well-dispersed TiO 2 -decorated carbon would be an effective strategy to enhance the ORR performance by strong metal-support interaction, which facilitated the electron transfer during catalytic reactions as well as prevented Pt aggregation during durability test.
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DOI
高影响因子
Energy Storage Materials
·
2019
·
IF 0
Pei Han,Mengsi Cheng,Donghai Luo,Wei Cui,Huichao Liu,Jianguo Du,Mingliang Wang,Yiping Zhao,Li Chen,Caizhen Zhu,Jian Xu
In consideration of the C-N bond is significantly weaker than C-C bond by about 30 kcal/mol, a selective etching of C-N bonds strategy has been put forward to prepare porous carbons with high specific surface area. The strategy has been characterized by a combination of experimental and theoretical techniques. The key to this success includes two-folds: the uniformly distributed C-N bonds and their preferential etching over the vast C-C bonds in the carbon precursors. Consequently, polydopamine with high nitrogen content is chosen as the precursor, through in situ C-N bond etching with KOH, a hierarchical porous carbon with an ultrahigh specific surface area of 3965 m 2 /g has been prepared, and the total pore volume is as high as 4.02 cm 3 /g. Specifically, the porous carbon showed a high specific capacitance of 342 F/g at 1 A/g and retained 268 F/g even at 10 A/g in 6 M KOH. Meanwhile, the symmetric supercapacitor devices deliver energy density of 29.2 Wh/kg at 347.5 W/kg and 20.7 Wh/kg at 10.3 kW/kg in 1 M Li 2 SO 4 aqueous electrolyte. Impressively, in organic electrolyte, it retains a high energy density of 80.8 Wh/kg even at 26.9 kW/kg.
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DOI
JOURNAL OF THE AMERICAN CERAMIC SOCIETY
·
2019
·Vol. 103
·期 1
·82-93
·
IF 3.094
Pengju Chen,Peng Xiao,Zhuan Li,Ling Pan,Jinwei Li,Zeyan Liu,Dongmei Pu,Yang Li
Mullite coating, SiC whiskers toughened mullite coating (SiC w -mullite), and cristobalite aluminum phosphate ( c -AlPO 4 ) particle modified SiC w -mullite coating ( c -AlPO 4 -SiC w -mullite) were prepared on SiC coated C/SiC composites using a novel sol-gel method combined with air spraying. Results show that molten SiO 2 formed by the oxidation of SiC whiskers and molten c -AlPO 4 improved the bonding strength between mullite outer coating and SiC–C/SiC composites due to their high-temperature bonding properties. The bonding strength between mullite, SiC w -mullite, c -AlPO 4 -SiC w -mullite outer coatings and SiC–C/SiC composites were 2.41, 4.31, and 7.38 MPa, respectively. After 48 thermal cycles between 1773 K and room temperature, the weight loss of mullite/SiC coating coated C/SiC composites was up to 11.61%, while the weight losses of SiC w -mullite/SiC and c -AlPO 4 -SiC w -mullite/SiC coatings coated C/SiC composites were reduced to 7.40% and 5.12%, respectively. The addition of appropriate SiC whiskers can considerably improve the thermal shock resistance of mullite coating owing to their excellent mechanical properties at high temperature. In addition, c -AlPO 4 particles can further improve the thermal shock resistance of SiC w -mullite coating due to their high-temperature bonding and sealing properties. No obvious micro-pores and cracks were observed on the surface of c -AlPO 4 -SiC w -mullite coating after 48 thermal cycles due to timely healing effect by formation of secondary mullite.
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高影响因子
CHINESE JOURNAL OF CATALYSIS
·
2025
·
IF 17.7
Xu Lin,Danyang Li,Shiqing Huang,Panpan Sun,Yan Huang,Shitao Wang,Lirong Zheng,Dapeng Cao
The limited activity of atomically-dispersed M-N-C electrocatalysts severely restricts their applicability in the oxygen reduction reaction (ORR) for proton exchange membrane fuel cells (PEMFC). Herein, we design and synthesize Se-doped Fe-N-C hierarchical porous electrocatalyst (FeN 4 /SeC 2 ) by optimizing carbon structure and FeN 4 coordination environment. The FeN 4 /SeC 2 electrocatalyst exhibits outstanding ORR activity in 0.1 mol L –1 HClO 4 , and the resulting PEMFC presents a peak power density of 1.20 W cm –2 in H 2 -O 2 condition at a back pressure of 200 kPa, ranking in the top levels among most reported non-precious metal catalyst-based fuel cells. The lower O 2 transfer resistance of FeN 4 /SeC 2 -based membrane electrode assembly than FeN 4 -based one means faster O 2 transport in triple-phase boundary (TPB), and Density functional theory calculation further reveals that the synergistic catalysis between porous SeC 2 and FeN 4 -OH species can efficiently lower the energy barriers for the rate-determining step of the ORR. In short, the outstanding performance of FeN 4 /SeC 2 in PEMFC is ascribed to the Se-doping, which introduces more defects and larger mesoporosity and therefore facilitates ionomer infiltration and O 2 transfer and charge transfer in TPB. The effective strategy of enhancing mass and charge transfers in TPB is anticipated to be applicable in the construction of highly efficient ORR electrocatalysts.
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高影响因子
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