JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
·
2020
·
IF 4.192
Jianghua Zhang,Ke Cheng,Hongyan Li,Fawen Yin,Qiaoe Wang,Li Cui,Shasha Yang,Jinggang Nie,Dayong Zhou,Beiwei Zhu
Catalytic production of structured phospholipids (SPLs) containing short-chain fatty acids (SCFAs) in an efficient heterogeneous manner is of great importance from the standpoint of food engineering. Herein, a bifunctionalized sulfonated Zn-SBA-15 catalyst was studied for SPL synthesis through interesterification of soybean lecithin with ethyl propionate or methyl butyrate. Various characterization techniques such as pyridine Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and ultraviolet–visible diffuse reflectance spectroscopy were conducted to determine the physicochemical properties, so as to build the possible structure–reactivity relationship of the catalyst. In screening tests with commercial Amberlyst-15 or other SBA-15-type materials, the as-prepared sample showed promising catalytic performance probably owing to its mesoporous structure and cooperative role of Brönsted and Lewis acid sites. Notably, the sample was easily separated and recycled without obvious deactivation. In general, the investigated catalyst was regarded as one of the promising alternatives to otherwise expensive biocatalysts for SCFA-containing SPL production.
研究领域:
食品工程
·
催化化学
·
生物化学
✓ 已验证
DOI
高影响因子
JOURNAL OF ANALYTICAL AND APPLIED PYROLYSIS
·
2024
·
IF 5.8
Liqiang Zhang,Ningmin Zhu,Chaochao Wang,Rongzheng Cui,Riyi Lin
Two-step catalytic pyrolysis of Nannochloropsis sp (NS) was conducted with SBA-15 and ZSM-5. Thermogravimetric analyzer (TG) and pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) were used to investigate the effects of SBA-15 and ZSM-5 on the two-step pyrolysis of NS. The comparative study showed that ZSM-5 and SBA-15 had different effects on the pyrolysis characteristic of NS because of their different property. ZSM-5 had no effects on the kinetic mechanism, but SBA-15 obviously changed DTG curves and the reaction order of the low temperature pyrolysis stage. SBA-15 increased the contents of amines and alkanes to 19.40% and 5.62% in the first step compared with those of the one-step pyrolysis (1.95% and 1.83%). Due to the stronger acid sites, ZSM-5 improved the content of olefins (33.79%) and esters (10.79%) in the first step and the contents of nitriles (11.75%) and aromatic hydrocarbons (31.01%) in the second step compared with those of one-step pyrolysis (10.61%, 5.41%, 0.00%, 8.42%). Acid catalyst had no positive effects on the generation of N-heterocyclic compounds. This study is expected to provide a reference for the efficient pyrolysis utilization of microalgae.
研究领域:
生物能源
·
催化化学
·
环境科学
✓ 已验证
DOI
高影响因子
FOOD CHEMISTRY
·
2018
·
IF 4.946
Nanjing Zhong,Weilin Chen,Liyan Liu,Hongxiao Chen
In this study, mesoporous silica SBA-15 was modified by organic functional groups through silanization. Series of organosilane compounds were grafted onto the SBA-15, and the obtained functionalized carriers were then used to immobilize the lipase from Rhizomucor miehei (RML). The enzymatic properties of the obtained immobilized RML samples were evaluated, and the catalytic efficiencies in glycerolysis of triacylglycerols (TAG) reaction were studied. Compared with the parent SBA-15 immobilized RML, the organic modification gave a maximum improvement of enzymatic activity from 200.00 to 13211.11 U/g; in addition, TAG conversion and diacylglycerols (DAG) content increased from 21.28 to 84.24% and 15.45 to 59.03% respectively. The organic modification also decreased the sensitivity of immobilized RML in extreme pH values and increased their thermostability.
研究领域:
生物化学
·
酶工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
MICROPOROUS AND MESOPOROUS MATERIALS
·
2017
·
IF 3.615
Mingsen Chen,Lanmei Qin,Yuanli Liu,Faai Zhang
Surface-initiated activators regenerated by electron transfer atom transfer radical polymerization (ARGET ATRP) was employed for controlled grafting of poly(glycidyl methacrylate) (PGMA) and poly(glycidyl methacrylate)-b-poly(methyl methacrylate) (PGMA-PMMA) brushes from mesoporous silica SBA-15. Initiator 2-bromoisobutyryl bromide (BiBB) was immobilized onto the inner surface of SBA-15 by reaction with free silanol groups. The polymerizations were conducted in the mixed solvents cyclohexanone /N, N-dimethylformamide. The strategy of utilizing mixed solvents gave rise to a suitable polymerization rate and resulted in a good control of the PGMA growth within the SBA-15 framework and could obtain polymer chains with well-preserved chain end functionality. Molecular weight of grafted polymer, structure, morphology, and composition of the functionalized SBA-15 were characterized by using gel permeation chromatography (GPC), X-ray powder diffraction (XRD), scanning electron microscope (SEM), transmission electron microscope (TEM), N 2 adsorption/desorption measurements, fourier transform infrared spectroscope (FT-IR), and thermogravimetry analysis (TGA), respectively. The thickness, polymer grafting density and molecular weight of the grafted polymer can be controlled by adjusting the polymerization time. The deactivator cannot efficient diffuse to convert the propagating chains to the dormant species when the pores are nearly completely filled with the polymer, therefore, increasing grafting density resulted in higher molecular weight and polydispersity index (PDI) values for the grafted polymer chains. This work provides a facile route for preparation of well-defined mesoporous silica/polymer hybrids.
研究领域:
材料科学
·
高分子化学
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2012
·Vol. 3
·期 7
·2227-2233
·
IF 0
Zhengping Dong,Xin Tian,Yuanzhe Chen,Jingran Hou,Jiantai Ma
Rhodamine group modified SBA-15 nanocomposite (R3-SBA-15) is investigated as a highly selective Hg2+ sensor. The colorless sensor converts to red color in the presence of Hg2+ with the fluorescent detection limit for Hg2+ in MeCN–H2O solution (9 : 1 v/v) being 15 ppb levels and exhibits excellent Hg2+-specific luminescence enhancement over various competitive cations, including alkali and earth, the first-row transition metals and heavy metals. According to the definition of Boolean Logic, using Hg2+ and S2− as inputs, the fluorescence intensity signal changes of R3-SBA-15 as outputs, R3-SBA-15 can act as an INHIBIT logic gate. All the results suggest that R3-SBA-15 was possible for real-time quantitative detection of Hg2+ and the convenience for potential application as a logic gate operated at the nanoscale level.
研究领域:
分析化学
·
纳米科学与技术
·
环境监测
·
生物传感
·
分子探针
✓ 已验证
DOI
CARBOHYDRATE POLYMERS
·
2017
·
IF 4.811
Xinran Xiang,Song Ding,Hongbo Suo,Chao Xu,Zhen Gao,Yi Hu
A nanocomposite (SBA-CIL-CS) which was combined mesoporous silica SBA-15 material with chitosan via ionic liquid as the bridging agent was successfully fabricated. The morphology and structure of the nanocomposite were characterized in detail with transmission electron microscope, fourier transform infrared spectroscopy, thermogravimetric analysis and nitrogen adsorption–desorption techniques. SBA-CIL-CS was investigated as an efficient support for immobilization of porcine pancreas lipase (PPL) and possessed high immobilization efficiency. The properties of immobilized enzyme (SBA-CIL-CS-PPL) such as activity, stability and reusability have been significantly improved, and a preferable pH and temperature tolerance were obtained as well. Results demonstrated the inorganic-organic nanocomposite could be used as an ideal support for enzyme immobilization.
研究领域:
生物材料
·
酶工程
✓ 已验证
DOI
高影响因子
CONSTRUCTION AND BUILDING MATERIALS
·
2025
·
IF 8
Shuyang Shi,Shuxian Zheng,Kun Zeng,Liang Yue,Xianlai Zhang,Wenhui Rao,Chuanbai Yu
The inflammability of epoxy resins (EPs) severely limits their safe and reliable application. The design and application of flame retardants has enormous potential for increasing the fire safety of EP composites. In the present study, a novel organic-inorganic nanohybrid material (VDSZ), consisting of mesoporous silica (SBA-15), P/N/Si-containing compound and the transition metal (Zn), was constructed by in-situ functional modification of the inner and outer surfaces of SBA-15. That is, Zn was in-situ modified on the inner pore surface of SBA-15, and phosphorus-containing compound was in-situ grafting onto outer surface of SBA-15 by Schiff base reaction. The results showed that EP/VDSZ-3 composite had a significant improvement in flame-retardant properties. The limiting oxygen index (LOI) for EP/VDSZ-3 increased from 24.5 % (EP) to 30.8 %, resulting in a UL-94 V-0 rating. Furthermore, the findings of the cone calorimeter test (CCT) demonstrated that, in comparison with pure EP, the peak heat release rate, total smoke generation and smoke production release of EP/VDSZ-3 decreased by 29.16 %, 25.95 %, and 30.90 % respectively. Moreover, the impact strength of EP/VDSZ-1 was 40 % higher than that of pure EP. Meanwhile, the thermal stability of EP composites improved dramatically as the VDSZ increased. This study found that creating a multi-level structure provided a fresh idea for simultaneously boosting polymer flame retardancy, smoke suppression and thermal stability, which will be applied to building materials with flame retardant requirements.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
BIOLOGICAL TRACE ELEMENT RESEARCH
·
2017
·Vol. 181
·期 1
·62-70
·
IF 2.399
Zhang Hui,Chang Zhenyu,Mehmood Khalid,Abbas Rao Zahid,Nabi Fazul,Rehman Mujeeb Ur,Wu Xiaoxing,Tian Xinxin,Yuan Xiaodan,Li Zhaoyang,Zhou Donghai
Nano-sized copper particles are widely used in various chemical, physical, and biological fields. However, earlier studies have shown that nano copper particles (40–100 μg/mL) can induce cell toxicity and apoptosis. Therefore, this study was conducted to investigate the role of nano copper in mitochondrion-mediated apoptosis in PK-15 cells. The cells were treated with different doses of nano copper (20, 40, 60, and 80 μg/mL) to determine the effects of apoptosis using acridine orange/ethidium bromide (AO/EB) fluorescence staining and a flow cytometry assay. The levels of malondialdehyde (MDA) and superoxide dismutase (SOD) in the PK-15 cells were examined using commercially available kits. Moreover, the mRNA levels of the Bax, Bid, Caspase-3, and CYCS genes were assessed by real-time PCR. The results revealed that nano copper exposure induced apoptosis and changed the mitochondrial membrane potential. In addition, nano copper significantly altered the levels of the Bax, Bid, Caspase-3, and CYCS genes at a concentration of 40 μg/mL. To summarize, nano copper significantly ( P < 0.05) decreased the level of SOD and increased the level of MDA in PK-15 cells. Altogether, these results suggest that nano copper can play an important role in inducing the apoptotic pathway in PK-15 cells, which may be the mechanism by which nano copper induces nephrotoxicity.
研究领域:
细胞生物学
·
毒理学
·
分子生物学
✓ 已验证
DOI
PubMed
高影响因子
Heliyon
·
2023
·
IF 4
Ding Nan,Hongzhi Fan,Altan Bolag,Wenhui Liu,Tana Bao
The Low utilization and high cost of platinum counter electrode (CE) in the application of dye-sensitized solar cells has limited its large-scale manufacturing in the industry. Herein, a facile pyrolysis combination of Pt and SBA-15 molecular sieve (MS) formed 1.6–1.9 times higher amount and 2–3 times reduced dimension of Pt distributed within porous structure of SBA-15. The composite CE with 20 % of SBA-15 exhibited an enhanced power conversion efficiency of 9.31 %, exceeding that of absolute Pt CE (7.57 %). This superior performance owed to the promoted oxidation-reduction rate of I 3 − /I − pairs at the CE interface and the increased conductivity of CE materials attributed from well distributed Pt particles. This work has demonstrated the significance of utilizing porous molecular sieves for dispersing catalytic sites when designing a novel type of counter electrode and their application in DSSCs.
研究领域:
材料科学
·
太阳能
·
电化学
✓ 已验证
DOI
高影响因子
ChemCatChem
·
2016
·Vol. 8
·期 6
·1199-1207
·
IF 4.724
Lan-Lan Lou,Shanshan Li,Huanling Du,Jiong Zhang,Wenjun Yu,Kai Yu,Shuangxi Liu
Graphical Short support : A short-mesochannel SBA-15 material is applied to the immobilization of a chiral 9-amino epicinchonine iridium catalyst, which exhibit excellent catalytic activity and notably improved enantioselectivity for the asymmetric transfer hydrogenation of aromatic ketones. A short-mesochannel SBA-15 material functionalized with propylthiol groups was prepared by co-condensation and applied to the immobilization of chiral 9-amino epicinchonine. After complexing with [Ir(cod)Cl] 2 (cod=1,5-cyclooctadiene), these mesoporous materials were evaluated as catalysts for the asymmetric transfer hydrogenation of aromatic ketones. Higher enantioselectivities and comparable, or even higher, catalytic activities were achieved compared with the free catalyst. Both the short mesochannel and co-condensation approach for short-mesochannel SBA-15 materials functionalized with propylthiol groups, [SSBA-SH( x )] materials were demonstrated to contribute to the excellent catalytic performance. In addition, the catalyst SSBA-AEC(5)/Ir (AEC=9-amino epicinchonine), with low 3-mercaptopropyltrimethoxysilane (MPTMS) content, showed the best catalytic performance; a high enantiomeric excess of 84 % (homogeneous ee =60 %) along with a conversion of 97 % was achieved within 1 h for asymmetric transfer hydrogenation of acetophenone. Moreover, these immobilized catalysts showed high stability during the reaction and could be recovered for reuse.
研究领域:
材料化学
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE
·
2019
·Vol. 100
·期 4
·1426-1435
·
IF 2.422
Xihong Zhao,Fenghuan Zhao,Nanjing Zhong
BACKGROUND In this study, SBA-15 was functionalized by silane coupling reagents, then lipase from Thermomyces lanuginosus (TLL) was immobilized onto the parent and the organically modified SBA-15 for diacylglycerol (DAG) production through glycerolysis. RESULTS Diacylglycerol content of 54.77 ± 0.63%, and triacylglycerol (TAG) conversion of 77.75 ± 1.24%, were obtained from the parent SBA-15 supported TLL-mediated glycerolysis reaction in a solvent-free system. However, poor performance was unexpectedly observed when co-solvents were introduced into the reaction system. After organic modification, the functionalized SBA-15 supported TLL samples all exhibited reasonable performance, producing DAG content over 40 wt% and TAG conversion over 70 wt%. Higher DAG content, up to 59.19 ± 1.10%, was observed from the phenyl group-modified SBA-15 supported TLL. The operational stability of the immobilized TLL samples in glycerolysis was also improved after organic functionalization. The phenyl group-modified SBA-15 supported TLL showed good reusability in the present glycerolysis reaction, and 95.21 ± 4.87% of the initial glycerolysis activity remained after five cycles of reuse. CONCLUSION The organic modification of SBA-15 improved the catalytic performance of its supported TLL in glycerolysis, in terms of TAG conversion, DAG content, and reusability. © 2019 Society of Chemical Industry
研究领域:
化学工程
·
生物催化
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
MICROPOROUS AND MESOPOROUS MATERIALS
·
2016
·
IF 3.349
Yan Liu,Jian Qiu,Yinhua Jiang,Zhanchao Liu,Minjia Meng,Liang Ni,Changchun Qin,Jianbo Peng
Ce(III) ion-imprinted polymer (Ce(III)-IIP) grafted on Fe 3 O 4 nanoparticles supported by SBA-15 mesopores microreactor was successfully synthesized via reversible addition-fragmentation chain transfer (RAFT) polymerization for selective removal of Ce(III) from aqueous solution. The characterization results suggest that the surface ion-imprinted polymer (IIP) synthesized by RAFT is a thin layer. Adsorption isotherm experiments indicated that Redlich-Peterson isotherm model best fitted the experimental data and the adsorption capacity of IIP was obviously higher than that of non-imprinted polymers (NIP) at the same conditions. The kinetics of adsorption followed the Thomas model. Moreover, competitive adsorption studies illustrated that Ce(III)-IIP offers the advantages of selectivity towards Ce(III) compared with NIP even in the presence of other metal ions. All above results indicated the potential application of Ce(III)-IIP for selective removal of Ce(III) from aqueous solution.
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
危险品化学品经营许可证（带存储）