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Characterization and catalytic properties of mesoporous CuO/SBA-16 prepared by different impregnation

DONG Yongli, YUAN Fulong, ZHU Yujun, ZHAO Lina, CAI Zhicheng

《化学科学与工程前沿(英文)》 2008年 第2卷 第2期   页码 150-154 doi: 10.1007/s11705-008-0036-x

摘要: CuO/SBA-16 catalysts were prepared by two different routes – the conventional impregnation method and the modified impregnation method with pH adjustment. These catalysts were characterized by X-ray diffraction (XRD), atomic absorption spectrometry (AAS), N physisorption and hydrogen temperature programmed reduction (H-TPR) measurements which reveal that the cubic cage-like () pore structure of the parent SBA-16 molecule sieves was well maintained throughout the synthesis. After introduction of Cu, a different CuO dispersion exists on these catalysts. The CuO/SBA-16 prepared by modified impregnation method has a single highly dispersed CuO which is considered as a highly efficient species for hydroxylation of phenol with HO. CuO/SBA-16 prepared by the conventional impregnation method shows the presence of bulk CuO species which is undesirable for this reaction.

关键词: different     CuO/SBA-16     temperature     physisorption     introduction    

Asymmetric transfer hydrogenation of prochiral ketone catalyzed over Fe-CS/SBA-15 catalyst

XUE Ping, WU Tao

《化学科学与工程前沿(英文)》 2007年 第1卷 第3期   页码 251-255 doi: 10.1007/s11705-007-0045-1

摘要: A heterogeneous chiral catalyst Fe(III)-CS (chitosan) complex/mesoporous molecular sieve SBA-15 (Santa Barbara Amorphous) was prepared. The asymmetric transfer hydrogenations of prochiral acetophenone and 4-methyl-2-pentanone to corresponding chiral alcohols were carried out on Fe-CS/SBA-15 at atmosphere pressure using 2-propanol as hydrogen donor. Effects of Fe content in catalyst, reaction temperature, reaction time and promoter KOH concentration on the conversion of substrates and enantioselectivity were investigated. Fe-CS/SBA-15 with 2.2% mass fraction Fe exhibits considerable enantioselectivity and catalytic activity for the asymmetric transfer hydrogenations of aromatic ketone and aliphatic ketone. Under optimal reaction conditions: KOH concentration 0.03 mol/L, reaction temperature 70ºC and reaction time 4 h, enantiomer excess (ee) of ()-1-phenylethanol and conversion of acetophenone can reach 87.4% and 27.7%, respectively. Under the above KOH concentration and reaction temperature and reaction time of 8 h, the ee of ()-4-methyl-2-pentanol and conversion 4-methyl-2-pentanone amounted to 50.2% and 25.5%, respectively.

关键词: asymmetric transfer     enantioselectivity     Fe-CS/SBA-15     aliphatic     aromatic    

Effects of preparation methods on the activity of CuO/CeO

Huanhuan Shang, Xiaoman Zhang, Jing Xu, Yifan Han

《化学科学与工程前沿(英文)》 2017年 第11卷 第4期   页码 603-612 doi: 10.1007/s11705-017-1661-z

摘要: CO oxidation has been investigated on three CuO/CeO catalysts prepared by impregnation, co-precipitation and mechanical mixing. The origin of active sites was explored by the multiple techniques. The catalyst prepared by impregnation has more highly dispersed CuO and stronger interactions between CuO and CeO to promote the reduction of CuO to Cu species at the Cu-Ce interface, leading to its highest catalytic activity. For the catalyst prepared by co-precipitation, solid solution structures observed in Raman spectra suppress the formation of the Cu-Ce interface, where the adsorbed CO will react with active lattice oxygen to form CO , and thus it displays a lower catalytic performance. No Cu-Ce interface exists in the catalyst prepared by the mechanical mixing method due to the separate phases of CuO and CeO , resulting in its lowest activity among the three catalysts.

关键词: CuO/CeO2     CO oxidation     interfaces     structure-performance relationship     active sites    

Effect of Cu-ZSM-5 catalysts with different CuO particle size on selective catalytic oxidation of N,N-Dimethylformamide

《环境科学与工程前沿(英文)》 2022年 第16卷 第10期 doi: 10.1007/s11783-022-1557-0

摘要:

● A series of Cu-ZSM-5 catalysts were tested for DMF selective catalytic oxidation.

关键词: N     N-Dimethylformamide     Selective catalytic oxidation     Cu-ZSM-5     CuO particle size    

Preparation of solar selective absorbing CuO coating for medium temperature application

HUANG Qunwu, WANG Yiping, LI Jinhua

《化学科学与工程前沿(英文)》 2007年 第1卷 第3期   页码 256-260 doi: 10.1007/s11705-007-0046-0

摘要: A new method of preparing CuO solar selective absorbing coating for medium temperature is presented. After pretreatment, brass was overlaid with CuO by chemical plating. The effects of reactant concentration, reaction temperature and reaction time on the absorptivity of CuO coating were investigated. The optimized condition of preparing CuO coating was obtained. The CuO coating was analyzed with X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM). In order to prolong the period of use, the CuO coating was protected by TiO. The experiment shows that the TiO/CuO coating is more heat-resistant, acid-resistant, and wear resistant than CuO coating, without losing absorptivity markedly. The TiO coating can reduce emissivity and protect the CuO coating.

关键词: photoelectron spectroscopy     temperature     pretreatment     absorptivity     microscopy    

Boehmite-supported CuO as a catalyst for catalytic transfer hydrogenation of 5-hydroxymethylfurfural

《化学科学与工程前沿(英文)》 2023年 第17卷 第4期   页码 415-424 doi: 10.1007/s11705-022-2225-4

摘要: 2,5-bis(hydroxymethyl)furan (BHMF) is an important monomer of polyester. Its oxygen-containing rigid ring structure and symmetrical diol functional group establish it as an alternative to petroleum-based monomer with unique advantages for the prodution of the degradable bio-based polyester materials. Herein, we prepared a boehmite-supported copper-oxide catalyst for the selective hydrogenation of 5-hydroxymethylfurfural into BHMF via catalytic transfer hydrogenation (CTH). Further, ethanol successfully replaced conventional high-pressure hydrogen as the hydrogen donor, with up to 96.9% BHMF selectivity achieved under suitable conditions. Through characterization and factor investigations, it was noted that CuO is crucial for high BHMF selectivity. Furthermore, kinetic studies revealed a higher by-product activation energy compared to that of BHMF, which explained the influence of reaction temperature on product distribution. To establish the catalyst structure-activity correlation, a possible mechanism was proposed. The copper-oxide catalyst deactivated following CTH because ethanol reduced the CuO, which consequently decreased the active sites. Finally, calcination of the catalyst in air recovered its activity. These results will have a positive impact on hydrogenation processes in the biomass industry.

关键词: biomass     5-hydroxymethylfurfural     2     5-bis(hydroxymethyl)furan     transfer hydrogenation     catalysis    

Cu/Cr co-stabilization mechanisms in a simulated AlO-FeO-CrO-CuO waste system

《环境科学与工程前沿(英文)》 2021年 第15卷 第6期 doi: 10.1007/s11783-021-1408-4

摘要:

• Cu and Cr can be mostly incorporated into CuFexAlyCr2xyO4 with a spinel structure.

关键词: Spinel structure     Copper     Chromium     Co-stabilization     Thermal treatment    

Enhanced desulfurization performance of hybrid membranes using embedded hierarchical porous SBA-15

Ye Zhang, Jian Song, Josue Quispe Mayta, Fusheng Pan, Xue Gao, Mei Li, Yimeng Song, Meidi Wang, Xingzhong Cao, Zhongyi Jiang

《化学科学与工程前沿(英文)》 2020年 第14卷 第4期   页码 661-672 doi: 10.1007/s11705-019-1830-3

摘要: The utilization of materials with a hierarchical porous structure as multi-functional additives is highly attractive in the preparation of hybrid membranes. In this study, novel hybrid membranes are designed by embedding hierarchical porous Santa Barbara Amorphous 15 (SBA-15) with a dual-pore architecture (micropores and mesopores) for pervaporation desulfurization. The SBA-15 with cylindrical mesopores provides molecular transport expressways to ensure improved permeability, while micropores on the wall have molecular sieving effects that are essential for the enhancement of permselectivity of thiophene molecules. Considering thiophene/ -octane mixture as a model system, the hybrid membrane with embedded 6 wt-% SBA-15 exhibits optimal pervaporation desulfurization performance with a permeation flux of 22.07 kg·m ·h and an enrichment factor of 6.76. Moreover, the detailed structure and properties of hybrid membranes are systematically characterized. This study demonstrates the immense potential of hierarchical porous materials as additives in membranes to simultaneously increase permeability and permselectivity.

关键词: hybrid membranes     hierarchical porous SBA-15     sieving effect     pervaporation     desulfurization    

Zfyve16 regulates the proliferation of B-lymphoid cells

Xuemei Zhao, Donghe Li, Qingsong Qiu, Bo Jiao, Ruihong Zhang, Ping Liu, Ruibao Ren

《医学前沿(英文)》 2018年 第12卷 第5期   页码 559-565 doi: 10.1007/s11684-017-0562-3

摘要:

Zfyve16 (a.k.a. endofin or endosome-associated FYVE-domain protein), a member of the FYVE-domain protein family, is involved in endosomal trafficking and in TGF-β, BMP, and EGFR signaling. The FYVE protein SARA regulates the TGF-β signaling pathway by recruiting Smad2/3 and accelerating their phosphorylation, thereby altering their susceptibility to TGF-β-mediated T cell suppression. Zfyve16 binds to Smad4 and their binding affects the formation of Smad2/3-Smad4 complex in TGF-β signaling. However, the in vivo function of Zfyve16 remains unknown. In this study, we generated a Zfyve16 knockout mouse strain (Zfyve16KO) and examined its hematopoietic phenotypes and hematopoietic reconstruction ability. The proportion of T cells in the peripheral blood of Zfyve16KO mice increases compared with that in wild-type mice. This finding is consistent with the role of Zfyve16 in facilitating TGF-β signaling. Unpredictably, B cell proliferation is inhibited in Zfyve16KO mice. The proliferation potential of Zfyve16KO B-lymphoid cells also significantly decreases in vitro. These results suggest that Zfyve16 inhibits the proliferation of T cells, possibly through the TGF-β signaling, but upregulates the proliferation of B-lymphoid cells.

关键词: Zfyve16     endofin     hematopoiesis     TGF-β     lymphocytes    

A mini review on chemical fixation of CO 2 : Absorption and catalytic conversion into cyclic carbonates

Weili DAI, Chaktong AU, Shenglian LUO, Shuangfeng YIN,

《化学科学与工程前沿(英文)》 2010年 第4卷 第2期   页码 163-171 doi: 10.1007/s11705-009-0235-0

摘要: In this article, we present our research results on chemical fixation of CO using organobismuth compounds. We fabricated bismuth biphenoate complex, Zn-Mg-Al composite oxides, and SBA-15 or Al-SBA-15 immobilized hydroxyl ionic liquid for CO cycloaddition onto epoxides. The hypervalent bismuth compounds show good ability for association and dissociation with CO. The bismuth biphenolate complexes are catalytically effective for the cycloaddition reaction. The heterogeneous catalysts, viz. Zn-Mg-Al oxides and SBA-15 or Al-SBA-15 immobilized ionic liquid, are efficient for the synthesis of cyclic carbonate from CO and epoxide. It is found that the presence of a trace amount of water can improve the catalytic activity of the immobilized ionic liquid.

关键词: SBA-15     CO cycloaddition     Al-SBA-15 immobilized     CO     dissociation    

CuO/zeolite catalyzed oxidation of gaseous toluene under microwave heating

Longli BO, Jianbo LIAO, Yucai ZHANG, Xiaohui WANG, Quan YANG

《环境科学与工程前沿(英文)》 2013年 第7卷 第3期   页码 395-402 doi: 10.1007/s11783-012-0417-8

摘要: The development of a combined process of catalytic oxidation and microwave heating for treatment of toluene waste gas was described in this work. Toluene, a typical toxic volatile organic compound, was oxidized through a fixed bed reaction chamber containing zeolite-supported copper oxide (CuO/zeolite) catalyst mixed with silicon carbide (SiC), an excellent microwave-absorbing material. The target compound was efficiently degraded on the surface of the catalyst at high reaction temperature achieved by microwave-heated SiC. A set of experimental parameters, such as microwave power, air flow and the loading size of CuO etc., were investigated, respectively. The study demonstrated these parameters had critical impact on toluene degradation. Under optimal condition, 92% toluene was removed by this combined process, corresponding to an 80%–90% TOC removal rate. Furthermore, the catalyst was highly stable even after eight consecutive 6-h runs. At last, a hypothetical degradation pathway of toluene was proposed based on the experimental data obtained from gas chromatography-mass spectrum and Fourier transform infrared spectroscopy analyses.

关键词: microwave     catalytic oxidation     CuO/zeolite catalyst     silicon carbide (SiC)     toluene    

Oxidation-extraction desulfurization of model oil over Zr-ZSM-5/SBA-15 and kinetic study

Chuanzhu LU,Hui FU,Huipeng LI,Hua ZHAO,Tianfeng CAI

《化学科学与工程前沿(英文)》 2014年 第8卷 第2期   页码 203-211 doi: 10.1007/s11705-014-1420-3

摘要: ZSM-5/SBA-15 composite molecular sieves were synthesized using post-synthesis method and characterized by X-ray diffraction and N adsorption-desorption. The oxidative-extration desulfurization of model oil was investigated by using hydrogen peroxide as the oxidant, tetrabutyl ammonium bromide as phase transfer catalyst, dimethyl sulfoxide as extractant, and Zr-ZSM-5/SBA-15, Ag-ZSM-5/SBA-15, Ce-ZSM-5/SBA-15 as catalyst. Under the optimal conditions, the desulfurization rate decreases in the order: Zr-ZSM-5/SBA-15>Ce-ZSM-5/SBA-15>Ag-ZSM-5/SBA-15. The highest desulfurization rate is 84.53% under the catalysis of Zr-ZSM-5/SBA-15. Kinetics analysis shows that the reaction is pseudo-first-order with the activation energy of 44.23 kJ/mol.

关键词: composite molecular sieve     oxidation desulfuration     extraction     kinetic    

RGS16 regulated by let-7c-5p promotes glioma progression by activating PI3K-AKT pathway

《医学前沿(英文)》 2023年 第17卷 第1期   页码 143-155 doi: 10.1007/s11684-022-0929-y

摘要: Gliomas are the most common central nervous system tumours; they are highly aggressive and have a poor prognosis. RGS16 belongs to the regulator of G-protein signalling (RGS) protein family, which plays an important role in promoting various cancers, such as breast cancer, pancreatic cancer, and colorectal cancer. Moreover, previous studies confirmed that let-7c-5p, a well-known microRNA, can act as a tumour suppressor to regulate the progression of various tumours by inhibiting the expression of its target genes. However, whether RGS16 can promote the progression of glioma and whether it is regulated by miR let-7c-5p are still unknown. Here, we confirmed that RGS16 is upregulated in glioma tissues and that high expression of RGS16 is associated with poor survival. Ectopic deletion of RGS16 significantly suppressed glioma cell proliferation and migration both in vitro and in vivo. Moreover, RGS16 was validated as a direct target gene of miR let-7c-5p. The overexpression of miR let-7c-5p obviously downregulated the expression of RGS16, and knocking down miR let-7c-5p had the opposite effect. Thus, we suggest that the suppression of RGS16 by miR let-7c-5p can promote glioma progression and may serve as a potential prognostic biomarker and therapeutic target in glioma.

关键词: RGS16     let-7c-5p     glioma     proliferation     migration    

Diverse bacterial populations of PM in urban and suburb Shanghai, China

《环境科学与工程前沿(英文)》 2021年 第15卷 第3期 doi: 10.1007/s11783-020-1329-7

摘要:

• Urban aerosols harbour diverse bacterial communities in Shanghai.

关键词: PM2.5     Bacteria     16S rRNA     SEM analysis     Shanghai City    

基于最小速率保证的IEEE 802-16e公平调度算法

史俊财,胡爱群,关艳峰

《中国工程科学》 2008年 第10卷 第2期   页码 54-59

摘要:

针对IEEE 802-16e协议的特点,提出了一种基于最小速率保证的IEEE 802-16e 公平 调度(MTRFS)算法。

关键词: IEEE 802-16e     调度算法     QoS     公平    

标题 作者 时间 类型 操作

Characterization and catalytic properties of mesoporous CuO/SBA-16 prepared by different impregnation

DONG Yongli, YUAN Fulong, ZHU Yujun, ZHAO Lina, CAI Zhicheng

期刊论文

Asymmetric transfer hydrogenation of prochiral ketone catalyzed over Fe-CS/SBA-15 catalyst

XUE Ping, WU Tao

期刊论文

Effects of preparation methods on the activity of CuO/CeO

Huanhuan Shang, Xiaoman Zhang, Jing Xu, Yifan Han

期刊论文

Effect of Cu-ZSM-5 catalysts with different CuO particle size on selective catalytic oxidation of N,N-Dimethylformamide

期刊论文

Preparation of solar selective absorbing CuO coating for medium temperature application

HUANG Qunwu, WANG Yiping, LI Jinhua

期刊论文

Boehmite-supported CuO as a catalyst for catalytic transfer hydrogenation of 5-hydroxymethylfurfural

期刊论文

Cu/Cr co-stabilization mechanisms in a simulated AlO-FeO-CrO-CuO waste system

期刊论文

Enhanced desulfurization performance of hybrid membranes using embedded hierarchical porous SBA-15

Ye Zhang, Jian Song, Josue Quispe Mayta, Fusheng Pan, Xue Gao, Mei Li, Yimeng Song, Meidi Wang, Xingzhong Cao, Zhongyi Jiang

期刊论文

Zfyve16 regulates the proliferation of B-lymphoid cells

Xuemei Zhao, Donghe Li, Qingsong Qiu, Bo Jiao, Ruihong Zhang, Ping Liu, Ruibao Ren

期刊论文

A mini review on chemical fixation of CO 2 : Absorption and catalytic conversion into cyclic carbonates

Weili DAI, Chaktong AU, Shenglian LUO, Shuangfeng YIN,

期刊论文

CuO/zeolite catalyzed oxidation of gaseous toluene under microwave heating

Longli BO, Jianbo LIAO, Yucai ZHANG, Xiaohui WANG, Quan YANG

期刊论文

Oxidation-extraction desulfurization of model oil over Zr-ZSM-5/SBA-15 and kinetic study

Chuanzhu LU,Hui FU,Huipeng LI,Hua ZHAO,Tianfeng CAI

期刊论文

RGS16 regulated by let-7c-5p promotes glioma progression by activating PI3K-AKT pathway

期刊论文

Diverse bacterial populations of PM in urban and suburb Shanghai, China

期刊论文

基于最小速率保证的IEEE 802-16e公平调度算法

史俊财,胡爱群,关艳峰

期刊论文