ACS Omega
·
2017
·
IF 0
Tingting Yang,Hu Li,Jian He,Yanxiu Liu,Wenfeng Zhao,Zhongwei Wang,Xiaoxiao Ji,Song Yang
γ-Valerolactone (GVL) is one of the versatile platform molecules and biofuel additives derived from the lignocellulosic biomass. Herein, the efficient synthesis of GVL from biobased ethyl levulinate (EL) using alcohol as both H-donor and solvent without an external hydrogen source has been achieved over porous Ti/Zr microspheres. The catalysts (TixZry) with different Ti/Zr molar ratios were synthesized using hexadecylamine (HDA) as a structure-directing agent via a sol–gel process combined with solvothermal treatment and characterized by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, thermal gravimetric analysis, NH3/CO2-TPD, N2 adsorption–desorption, and pyridine-IR. A high GVL yield of 90.1% at 100% EL conversion was obtained at 180 °C for 6 h over Ti2Zr8 in 2-propanol. The microspheric and porous structure, enhanced surface areas, and acid/base contents by the proper introduction of Ti species into Zr oxide were demonstrated to be responsible for the pronounced performance. The microspheric Ti2Zr8 porous catalyst could be reused at least six times with no decrease in catalytic activity.
研究领域:
催化化学
·
生物质转化
·
材料科学
✓ 已验证
DOI
CERAMICS INTERNATIONAL
·
2021
·Vol. 47
·期 19
·26869-26876
·
IF 4.527
Shao-Min Lin,Ya-Ling Yu,Ming-Feng Zhong,Huan Yang,Chen-Yang Zhang,Zhi-Jie Zhang,Wei Xu,Jiong-Yan Xie,Yu-Chun Qiu
Converting the γ phase into the α phase completely is necessary in the presintering stage of industrial alumina (Al 2 O 3 ), which requires high temperature and energy consumption. To reduce the presintering temperature, γ-Al 2 O 3 was activated by oxalic acid . XRD , 27 Al-MAS-NMR and TG-DSC were used to characterize the γ - alumina before and after activation, and the phase transformation was studied. The formation temperature of α-Al 2 O 3 decreased to 1029 °C for oxalic acid activated γ-Al 2 O 3 , and the α-fraction was 100% for activated γ-Al 2 O 3 at 1300 °C. After oxalic acid activation , the diffraction peak intensity of γ-Al 2 O 3 decreased significantly; the results of 27 Al-MAS-NMR suggested that octahedral [AlO 6 ] in γ-Al 2 O 3 was easier than tetrahedral [AlO 4 ] to be attacked by oxalic acid , and the formation of pentavalent [AlO 5 ] with higher reaction activity, which was in favour of the lowering formation temperature of α-Al 2 O 3 . The dissolution concentration of Al increased after oxalic acid activation, and the dissolution process was controlled by surface reactions. Oxalic acid mainly attacked the octahedral aluminium in γ-Al 2 O 3 and extracted Al as three complexes of [Al(C 2 O 4 )] + , [Al(C 2 O 4 ) 2 ] - and [Al(C 2 O 4 ) 3 ] 3- . Oxalic acid activated γ - Al 2 O 3 with a lower phase transformation temperature has broad application prospects in the alumina industry.
研究领域:
材料化学
·
无机化学
·
固态化学
·
工业催化
·
陶瓷材料
✓ 已验证
DOI
高影响因子
FUEL
·
2018
·
IF 4.908
Hui-Chao Hu,Shaokai Zhang,Tong Zeng,Yiying Lin,Liulian Huang,Lihui Chen,Yonghao Ni
In this paper, a robust method based on solvent-volume controlled full evaporation headspace gas chromatography technique (FE HS-GC) was developed to high throughput quantify γ-valerolactone (GVL) concentration in sample solution. The results showed that the full evaporation of GVL can be achieved by the equilibration process in headspace sampler at 150 °C for 5 min. For eliminating the matrix effect and pressure effect on GVL quantification, the sample volume added in headspace vial should be controlled within 15 μL. The present method was proved that has a very high precision (error < 1.11%), high precision (recoveries from 95.6% to 102.1%), and an excellent limit of quantification (153 mg/L). The present method was applied in valuation of GVL yield in a heterogeneous catalytic system and its recovery in a GVL-based biomass pretreatment process, and has given some valuable information. The present method is simple, rapid, efficient, and can be an excellent tool for screening reaction medium and catalysts in GVL synthesis and its related biorefinery processes.
研究领域:
分析化学
·
生物工程
✓ 已验证
产品关联
DOI
高影响因子
Journal of Energy Chemistry
·
2024
·
IF 14
Haojun Wu,Zhangyating Xie,Guanjie Li,Lei Zheng,Zhiwei Zhao,Jiarong He,Yanbin Shen,Jiahao Hu,Zhangquan Peng,Guiming Zhong,Lidan Xing,Weishan Li
Developing wide-temperature and high-safety lithium-ion batteries (LIBs) presents significant challenges attributed to the absence of suitable solvents possessing broad liquid range and non-flammability properties. γ-Butyrolactone (GBL) has emerged as a promising solvent; however, its incompatibility with graphite anode has hindered its application. This limitation necessitates a comprehensive investigation into the underlying mechanisms and potential solutions. In this study, we achieve a molecular-level understanding of the perplexing interphase formation process by employing in-situ spectroelectrochemical techniques and density function calculations. Our findings reveal that, even at high salt concentrations, GBL consistently occupies the primary Li + solvation sheath, leading to extensive GBL decomposition and the formation of a high-impedance and inorganic-poor solid-electrolyte interphase (SEI) layer. Contrary to manipulating solvation structures, our research demonstrates that the utilization of film-forming additives with higher reduction potential facilitates the pre-establishment of a robust SEI film on the graphite anode. This approach effectively inhibits GBL decomposition and significantly enhances the battery's lifespan. This study provides the first reported intrinsic understanding of the unique GBL-graphite incompatibility and offers valuable insights for the development of wide-temperature and high-safety LIBs.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
TALANTA
·
2020
·
IF 5.339
Zhentao Li,Zhenkun Mao,Wei Zhou,Zilin Chen
Metal-organic frameworks (MOFs) are a novel class of porous nanomaterials composed of metals and organic linkers that have been used in many fields. A novel stereoselective stationary phase for capillary electrochromatography (CEC) has been developed in this work by employing a biodegradable, easier-to-prepare and green homochiral MOFs (Cu-SD), which composed of octakis-[6-deoxy-6-(3-mercaptopropanoic sodium)]-γ-cyclodextrin (SD, sugammadex) and transition metal ion (Cu 2+ ) supported by polydopamine as linker. The modified capillary was characterized by scanning electron microscopy (SEM), X-ray spectrometry (XRD), energy dispersive (EDS) and Fourier transform infrared spectroscopy (FT-IR). The Cu-SD modified capillary column exhibited outstanding chiral recognition separation for five Dns-DL-amino acids (the DL-forms of phenylalanine , leucine , valine , threonine , serine). In addition, the modified column showed excellent stability and reproducibility. The relative standard deviations (RSDs) of the retention time for intra-day (n = 5) and inter-day (n = 3) and between columns (n = 3) enantioseparations were less than 0.27, 1.45 and 4.88%, respectively. Conceivably, this new-type of γ-CD-MOF represents a useful chiral stationary phase in electrochromatographic separations, and it has great potential in chiral separation field.
研究领域:
分析化学
·
材料科学
·
药物化学
✓ 已验证
DOI
高影响因子
RSC Advances
·
2021
·Vol. 11
·期 31
·18738-18747
·
IF 3.361
Dingyao Gao,Yinxing Miao,Siqin Ye,Chunmei Lu,Gaochao Lv,Ke Li,Chunjing Yu,Jianguo Lin,Ling Qiu
The expression level of γ-glutamyltranspeptidase (GGT) in some malignant tumors is often abnormally high, while its expression is low in normal tissues. Therefore, GGT is considered as a key biomarker for cancer diagnosis. Several GGT-targeting fluorescence probes have been designed and prepared, but their clinical applications are limited due to their shallow tissue penetration. Considering the advantages of positron emission tomography (PET) such as high sensitivity and deep tissue penetration, we designed a novel PET imaging probe for targeted monitoring of the expression of GGT in living subjects, ([18F]γ-Glu-Cys-PPG(CBT)-AmBF3)2, hereinafter referred to as ([18F]GCPA)2. The non-radioactive probe (GCPA)2 was synthesized successfully and [18F]fluorinated rapidly via the isotope exchange method. The radiotracer ([18F]GCPA)2 could be obtained within 0.5 h with the radiochemical purity over 98% and the molar activity of 10.64 ± 0.89 GBq μmol−1. It showed significant difference in cellular uptake between GGT-positive HCT116 cells and GGT-negative L929 cells (2.90 ± 0.12% vs. 1.44 ± 0.15% at 4 h, respectively). In vivo PET imaging showed that ([18F]GCPA)2 could quickly reach the maximum uptake in tumor (4.66 ± 0.79% ID g−1) within 5 min and the tumor-to-muscle uptake ratio was higher than 2.25 ± 0.08 within 30 min. Moreover, the maximum tumor uptake of the control group co-injected with the non-radioactive probe (GCPA)2 or pre-treated with the inhibitor GGsTop decreased to 3.29 ± 0.24% ID g−1 and 2.78 ± 0.32% ID g−1 at 10 min, respectively. In vitro and in vivo results demonstrate that ([18F]GCPA)2 is a potential PET probe for sensitively and specifically detecting the expression level of GGT.
研究领域:
医学影像学
·
肿瘤学
·
分子生物学
✓ 已验证
DOI
PubMed
高影响因子
Journal of Environmental Chemical Engineering
·
2024
·
IF 7.4
Yanli Zhang,Jian Li,Jianyu Cai,Shuangye Li,Xing Fan,Liyun Song,Ruixue Guo,Jiasheng Liu
In this study, a series of γ-Fe 2 O 3 -modified V 2 O 5 -MoO 3 /TiO 2 (VMT) catalysts was prepared by wet impregnation method. The γ-Fe 2 O 3 -modified catalysts exhibited excellent catalytic performance, and 1.25 wt% γ-Fe 2 O 3 content improved the deNO x efficiency at 150 °C from 54% (unmodified VMT catalyst) to 84% (modified catalyst). BET, XRD, XPS, NH 3 -TPD, H 2 -TPR, and in situ DRIFTs were employed to characterize the physicochemical properties and reaction mechanisms of the catalysts. The introduction of γ-Fe 2 O 3 increased the V 5+ /V 4+ ratio, surface chemisorbed oxygen content, redox ability, and a number of acid sites in the prepared catalysts. XPS confirmed the addition of γ-Fe 2 O 3 introduced new charge transfer pathways (Fe 3+ /Fe 2+ ↔ V 5+ /V 4+ ). In situ DRIFTs suggested that the addition of γ-Fe 2 O 3 to the catalyst significantly increased the adsorption capacity of catalyst for NH 3 and NO x , while also exerting a strong activating effect on the adsorbed NH 3 . Furthermore, selective catalytic reduction over the VMT and 5PEG@1.25Fe-VMT catalysts followed the Eley-Rideal (E-R) mechanism. At temperatures above 200 °C, the 5PEG@1.25Fe-VMT catalyst also followed the Langmuir-Hinshelwood (L-H) mechanism.
研究领域:
环境科学
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Chemical Information and Modeling
·
2025
·
IF 5.3
Binbin Chen,Jiahui Huang,Yingchun Liu,Lirong Yang,Qi Wang,Haoran Yu
The catalytic mechanism of a pyridoxal 5′-phosphate (PLP)-dependent UstD was herein studied in atomic detail, employing the computational hybrid QM/MM methodology. UstD is a PLP-dependent enzyme that catalyzes the decarboxylative aldol reactions between l-aspartate and aldehyde or ketone derivatives to form γ-hydroxy-α-amino acids. In the reaction catalyzed by UstD, the loss of CO2 renders the C–C bond-forming reaction effectively irreversible, which makes UstD a special case among the enzymes catalyzing the C–C bond-forming reactions. This enzyme is currently seen as the optimal approach for the regioselective synthesis of γ-hydroxy-α-amino acids, which are very difficult to obtain by standard chemical methods. The results obtained herein showed that the catalytic mechanism of UstD might follow two paths to occur in three phases: (1) decarboxylation of substrate l-aspartate, (2) C–C bond formation by addition of aldehyde, and (3) the regeneration of catalytic sites. Although Path A and Path B showed a negligible difference in the energy barrier of the rate-determining step, Path A involves three additional steps in the overall pathway compared with Path B, which makes the reaction proceed more readily through Path B. According to the QM/MM energy profile of Path B, the rate-limiting step of the catalytic process is the decarboxylation of the side chain of l-aspartate, which has a calculated energy barrier of 19.19 kcal/mol. Two crucial residues, H263 and Y257, were identified to interact with the substrate aspartic acid. The knowledge about the transition states, intermediates, key residues, and protein conformational changes along the reaction path will be valuable for engineering UstD to improve the synthesis of γ-hydroxy-α-amino acids that serve as building blocks of various high-value chemicals such as antidiabetics and nutritional supplements.
研究领域:
生物化学
·
计算生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHINESE JOURNAL OF CHEMICAL PHYSICS
·
2017
·Vol. 30
·期 2
·231-238
·
IF 0.498
Lin Fu-xing,Zeng Kun,Yang Wen-xiu,Wang Mo-zhen,Rong Jie-lin,Xie Juan,Zhao Yu,Ge Xue-wu
Chitosan (CS) is expected to be an ideal gene carrier for its high biosafety. In this work, CS with low molecular weight were prepared through the γ -ray radiation on the acetic acid solution of CS. The CS chains were scissioned under the γ -ray radiation, and the molecular weight (MW) of CS decreased with the absorbed dose. When the absorbed dose was above 30 kGy, the molecular weight of CS decreased about an order of magnitude. The γ -ray-radiation-scissioned CS can effectively bind with plasmid (pEGFP) through complex coacervation method, forming pEGFP/ γ -ray-radiation-scissioned CS complex particles with a size of 200–300 nm. The complex particles have good stability and little cytotoxicity. The in vitro gene transfection efficiencies of the pEGFP/ γ -ray-radiation-scissioned CS complex particles were investigated by fluorescence microscope and flow cytometry. The results showed that the gene vectors using γ -ray-radiation-scissioned CS as the carrier will possess better gene transfection efficiency than those using natural high-MW CS as the carrier. The higher the absorbed dose, the smaller the MW of CS and the better transfection efficiency of the corresponding gene vector. This work provides a green and simple method on the preparation of CS-based gene vectors with high efficiency and biosafety.
研究领域:
生物材料学
·
基因治疗
·
放射化学
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2024
·
IF 8.3
Chuxiong Huang,Jingxi Liang,Huayan Xiao,Xiujuan Wei,Tiefeng Liu,Zhan Lin,Shuxing Wu
SiOx is a highly promising anode material for realizing high-capacity lithium-ion batteries owing to its high theoretical capacity. However, the large volume change during cycling limits its practical application. The development of a binder has been demonstrated as one of the most economical and efficient strategies for enhancing the SiOx anode’s electrochemical performance. In this work, a multifunctional binder (T-PGA) is fabricated by cross-linking γ-polyglutamic acid (PGA) and tannic acid (TA) for SiOx anodes. The introduction of TA into PGA helps to buffer the volume changes of the SiOx anodes, facilitate diffusion of Li+, and construct stable SEI layers. Benefiting from this proposed binder, the SiOx anode maintains a reversible capacity of 973.0 mAh g–1 after 500 cycles at 500 mA g–1 and the full cell, pairing with LiNi0.5Co0.2Mn0.3O2 cathode, delivers a reversible capacity of 133 mA h g–1 (73.2% retention) after 100 cycles. This study offers valuable insights into advanced binders that are used in high-performance Li-ion batteries.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Catalysts
·
2024
·Vol. 14
·期 2
·113
·
IF 3.8
Hongzhi Ding,Chenyu Yang,Congyan Jiang,Wei Luo,Qiuyue Wang,Xuefeng Guo
The use of eco-friendly biomass as a resource is an efficient way to address the problems of fossil fuel depletion and climate change. In biomass conversion, versatile γ-valerolactone (GVL) is generally obtained from levulinic acid (LA) hydrogenation via a multimetallic catalyst system. Despite conversion efficiency being enhanced in mild conditions due to metal interactions, maintaining high catalyst stability is still a challenge. In this study, we synthesized a surrounded Co0.52Ni0.48@Al2O3-IE catalyst that exhibited excellent alloying and synergistic interaction between the metal constituents. Under relatively mild reaction conditions, the GVL yield over the catalyst exceeded 99% in LA hydrogenation. The catalyst showed no deactivation in a test of five cycles, displaying superiority in stability, possibly due to reasons of the physical isolation of the shell and the alumina retention on the Co-Ni alloys surface caused by the reversibility of exchange equilibrium. The present work demonstrated that a surrounded structured catalyst fabricated by ion exchange (IE) with active metals physically enclosed can lead to high catalytic activity and superior stability.
研究领域:
催化化学
·
可再生能源
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2024
·
IF 8.3
Pengyu Yuan,Qing Wang,Xuelei Deng,Xiaoyan Zhang,Daidi Fan,Yunpeng Bai
Enzyme catalysis is a promising method for producing chiral chemicals with high stereoselectivity under mild conditions. However, the traditional batch reaction suffers from low enzyme stability, low cofactor recycling, and poor enzyme reusability. Here, we present a continuous-flow method using coimmobilized dual enzymes for the synthesis of chiral γ-/δ-lactones, which are widely used in fragrances and flavors. Typically, a carbonyl reductase mutant SmCRM5 from Serratia marcescens, was coimmobilized by covalent binding with BmGDH, a glucose dehydrogenase capable of recovering and recycling the cofactor NADPH. After immobilization, SmCRM5 and BmGDH exhibited a 8.9-/8.7-fold increase in catalytic efficiency (kcat/Km) and a 57-/15-fold increase in half-life at 30 °C, respectively. We demonstrated that coimmobilized dual enzymes used in a continuous flow reactor showed a higher reaction rate and a higher space-time yield (1586 g·L–1 d–1) than free enzymes and immobilized enzymes in a batch reaction for the production of (R)-δ-decalactone. This continuous flow reactor can run continuously for more than 650 h with 99% ee and 80% conversion, and the total volume exceeds 1500 reactor volumes. The robustness of this continuous-flow immobilized enzyme system provides a green and efficient method for the synthesis of high value-added chiral chemicals.
研究领域:
生物催化
·
酶工程
·
绿色化学
✓ 已验证
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）