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Comparison study on strategies to prepare nanocrystalline Li

Qiang XIAO, Xiaodan TANG, Yefeng LIU, Yijun ZHONG, Weidong ZHU

《化学科学与工程前沿（英文）》 2013年第7卷第3期页码 297-302 doi: 10.1007/s11705-013-1346-1

摘要： A comparison study has been conducted on the strategies for synthesizing nanocrystalline Li ZrO and K-doped Li ZrO absorbents for CO capture at high temperatures, including solid-state and liquid-phase methods, citrate route, and starch-assisted sol-gel method combined with freeze-drying technique. The absorption properties, including uptake rate and absorption capacity, of synthesized absorbents were investigated by thermogravimetric analysis (TGA) at different CO partial pressures. The nanosized Li ZrO crystals synthesized by the citrate route exhibit a faster uptake and a higher, nearly stoichiometric absorption capacity than those synthesized by the solid-state and liquid-phase methods. The doping of K into Li ZrO can significantly improve the uptake rate of CO , especially at low CO partial pressures. For the synthesis of K-doped Li ZrO , the citrate route has poor reproducibility and scalability, whereas the starch-assisted sol-gel method combined with freeze-drying technique is reproducible and easily scaled up, and the thus synthesized absorbents possess excellent CO capture properties.

关键词： CO₂ capture Li₂ZrO₃ K-doped Li₂ZrO₃ citrate starch freeze-drying technique

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Preparation and characterization of nanocrystalline ZrO2-7%Y2O3 powders for thermal barrier coatings

Kirsten BOBZIN, Lidong ZHAO, Thomas SCHLAEFER, Thomas WARDA

《机械工程前沿（英文）》 2011年第6卷第2期页码 176-181 doi: 10.1007/s11465-011-0220-4

摘要：

High-energy ball milling is an effective method to produce nanocrystalline oxides. In this study, a conventional ZrO₂-7%Y₂O₃spray powder was ball-milled to produce nanocrystalline powders with high levels of crystalline disorders for deposition of thermal barrier coatings. The powder was milled both with 100Cr6 steel balls and with ZrO₂-3%Y₂O₃ ceramic balls as grinding media. The milling time was varied in order to investigate the effect of the milling time on the crystallite size. The powders were investigated in terms of their crystallite sizes and morphologies by X-ray diffraction analysis (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The results show that under given milling conditions the powder was already nanostructured after 40 min milling. The crystallite size decreased significantly with increasing milling time within first 120 min. After that, a further increase of milling time did not lead to a significant reduction of the crystallite size. Ball-milling led to lattice microstrains. Milling with the steel balls resulted in finer nano-sized crystal grains, but caused the contamination of the powder. The nano-sized crystal grains coarsened during the heat-treatment at 1250°C.

关键词： nanostrucured powders yttria stabilized zirconia (YSZ) high-energy ball milling thermal barrier coatings

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A simple and cheap method for preparation of coupled ZrO2/ZnO with high photocatalytic activities

WANG Zheng, ZHANG Bingru, LI Fengting

《环境科学与工程前沿（英文）》 2007年第1卷第4期页码 454-458 doi: 10.1007/s11783-007-0072-7

摘要： The objective of this study was to prepare a new photocatalyst with high activities for degradation of organic pollutants. Coupled ZrO/ZnO photocatalyst was prepared with a simple precipitation method with cheap raw

关键词： objective ZrO/ZnO photocatalyst photocatalyst precipitation degradation

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Enhanced performance of oxygen vacancies on CO adsorption and activation over different phases of ZrO

《能源前沿（英文）》 2023年第17卷第4期页码 545-554 doi: 10.1007/s11708-023-0867-7

摘要： The effect of oxygen vacancies on the adsorption and activation of CO₂ on the surface of different phases of ZrO₂ is investigated by density functional theory (DFT) calculations. The calculations show that the oxygen vacancies contribute greatly to both the adsorption and activation of CO₂. The adsorption energy of CO₂ on the c-ZrO₂, t-ZrO₂ and, m-ZrO₂ surfaces is enhanced to 5, 4, and 3 folds with the help of oxygen vacancies, respectively. Moreover, the energy barrier of CO₂ dissociation on the defective surfaces of c-ZrO₂, t-ZrO₂, and m-ZrO₂ is reduced to 1/2, 1/4, and 1/5 of the perfect surface with the assistance of oxygen vacancies. Furthermore, the activation of CO₂ on the ZrO₂ surface where oxygen vacancies are present, and changes from an endothermic reaction to an exothermic reaction. This finding demonstrates that the presence of oxygen vacancies promotes the activation of CO₂ both kinetically and thermodynamically. These results could provide guidance for the high-efficient utilization of CO₂ at an atomic scale.

关键词： CO₂ activation oxygen vacancies ZrO₂ different phases

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Visbreaking of heavy petroleum oil catalyzed by SO/ZrO solid super-acid doped with Ni or Sn

JING Ping, LI Qingbiao, HAN Mei, SUN Daohua, JIA Lishan, FANG Weiping

《化学科学与工程前沿（英文）》 2008年第2卷第2期页码 186-190 doi: 10.1007/s11705-008-0035-y

摘要： SO/ZrO solid super-acid catalysts (SZ) doped with Ni or Sn (Ni/SZ, Sn/SZ) were prepared for catalytic visbreaking of heavy petroleum oil from Shengli oil field. The visbreaking reactions were carried out at 240°C and 3–4 MPa for 24 h using a heavy petroleum oil to catalyst mass ratio of 100 : 0.05. The effect of water content on viscosity of heavy petroleum oil was also investigated. Both catalysts can promote thermolysis of heavy petroleum oil and the viscosity was reduced from 0.319 Pa·s to 0.135 Pa·s for Ni/SZ and 0.163 Pa·s for (Sn/SZ) with visbreaking rates of 57.7% and 48.9%, respectively. After visbreaking, the saturated hydrocarbon content increased while aromatics, resin, asphaltene, sulfur and nitrogen content decreased. The presence of water was disadvantageous to visbreaking of heavy petroleum oil.

关键词： thermolysis Shengli asphaltene SO/ZrO presence

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Effect of TiO 2 loading on the activity of V/TiO 2 -Al 2 O 3 in the catalytic oxidehydrogenation of ethylbenzene

Xiaohong LI, Wenying LI,

《化学科学与工程前沿（英文）》 2010年第4卷第2期页码 142-146 doi: 10.1007/s11705-009-0233-2

摘要： TiO-AlOmixed oxides with different compositions ranging from 40wt-% to 95wt-% of TiO were prepared by sol-gel method and impregnated with different amounts of VO. Supports and catalysts were characterized by X-ray diffraction (XRD), physisorption, temperature preprogrammed reduction (H-TPR), and ammonia temperature programmed desorption (NH-TPD). TiO content in the support had obvious effect on the crystal structure, texture characteristic, acid property, and catalytic activity in dehydrogenation of ethylbenzene (EB) with carbon dioxide. The highest catalytic activity was acquired when the TiO content was 50 wt-%.

关键词： desorption different TiO-AlOmixed physisorption ethylbenzene

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Preparation of Cu/ZrO

Xinmei LIU, Shaofen BAI, Huidong ZHUANG, Zifeng YAN

《化学科学与工程前沿（英文）》 2012年第6卷第1期页码 47-52 doi: 10.1007/s11705-011-1170-4

摘要： Cu/ZrO catalysts for methanol synthesis from CO /H were respectively prepared by deposition coprecipitation (DP) and solid state reaction (SR) methods. There is an intimate interaction between copper and zirconia, which strongly affects the reduction property and catalytic performance of the catalysts. The stronger the interaction, the lower the reduction temperature and the better the performance of the catalysts. Surface area, pore structure and crystal structure of the catalysts are mainly controlled by preparation methods and alkalinity of synthesis system. The conversion of CO and selectivity of methanol are higher for DP catalysts than for SP catalysts.

关键词： Cu/ZrO₂ methanol synthesis deposition coprecipitation solid state reaction CO₂/H₂

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Stability of Ni/SiO

Bettina Stolze,Juliane Titus,Stephan A. Schunk,Andrian Milanov,Ekkehard Schwab,Roger Gläser

《化学科学与工程前沿（英文）》 2016年第10卷第2期页码 281-293 doi: 10.1007/s11705-016-1568-0

摘要： Ni/SiO -ZrO catalysts with Ni loadings of 1 to 13 wt-% were prepared, characterized by elemental analysis, X-ray diffraction, N sorption, temperature programmed oxidation, temperature programmed reduction, and tested for their activity and stability in the dry reforming of methane with carbon dioxide at 850 °C, gas hourly space velocity of 6000 and 1800 h and atmospheric pressure. The SiO -ZrO support as obtained through a simple and efficient sol-gel synthesis is highly porous ( = 90 m ·g , = 4.4 nm) with a homogeneously distributed Si-content of 3 wt-%. No loss of Si or formation of monoclinic ZrO , even after steaming at 850 °C for 160 h, was detectable. The catalyst with 5 wt-% Ni loading in its fully reduced state is stable over 15?h on-stream in the dry reforming reaction. If the catalyst was not fully reduced, a reduction during the early stages of dry reforming is accompanied by the deposition of up to 44 mg·g carbon as shown by experiments in a magnetic suspension balance. Rapid coking occurs for increased residence times and times-on-stream starting at 50 h. The Ni loading of 5 wt-% on SiO -ZrO was shown to provide an optimal balance between activity and coking tendency.

关键词： Ni/SiO₂-ZrO₂ synthesis gas dry reforming coking steaming

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CO₂ methanation and co-methanation of CO and CO₂ over Mn-promoted Ni/Al₂O₃ catalysts

Kechao Zhao,Zhenhua Li,Li Bian

《化学科学与工程前沿（英文）》 2016年第10卷第2期页码 273-280 doi: 10.1007/s11705-016-1563-5

摘要： A series of Mn-promoted 15 wt-% Ni/Al O catalysts were prepared by an incipient wetness impregnation method. The effect of the Mn content on the activity of the Ni/Al O catalysts for CO methanation and the co-methanation of CO and CO in a fixed-bed reactor was investigated. The catalysts were characterized by N physisorption, hydrogen temperature-programmed reduction and desorption, carbon dioxide temperature-programmed desorption, X-ray diffraction and high-resolution transmission electron microscopy. The presence of Mn increased the number of CO adsorption sites and inhibited Ni particle agglomeration due to improved Ni dispersion and weakened interactions between the nickel species and the support. The Mn-promoted 15 wt-% Ni/Al O catalysts had improved CO methanation activity especially at low temperatures (250 to 400 °C). The Mn content was varied from 0.86% to 2.54% and the best CO conversion was achieved with the 1.71Mn-Ni/Al O catalyst. The co-methanation tests on the 1.71Mn-Ni/Al O catalyst indicated that adding Mn markedly enhanced the CO methanation activity especially at low temperatures but it had little influence on the CO methanation performance. CO methanation was more sensitive to the reaction temperature and the space velocity than the CO methanation in the co-methanation process.

关键词： Mn promotion nickel catalysts CO₂ methanation co-methanation of CO and CO₂

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Synthesis of copolymers of 3-acryloyloxymethyl-3′-methyloxetane and 3-(2-(2-(2-Methoxyethylenoxy)ethylenoxy)ethylenoxy)-3′-methyloxetane and their ionic conductivity properties

YE Lin, ZHAO Yumei, FENG Zengguo, BAI Ying, WU Feng

《化学科学与工程前沿（英文）》 2007年第1卷第4期页码 343-348 doi: 10.1007/s11705-007-0062-0

摘要： An oxetane-derived monomer, 3-acryloyloxymethyl-3′-methyloxetane (AMO) was prepared from the reaction of 3-hydromethyl-3-methyloxetane with acryloyl chloride. The cationic ring-opening copolymerization of AMO with another oxetane-derived monomer, 3-(2-(2-(2-methoxyethylenoxy)ethylenoxy)ethylenoxy)-3′-methyloxetane (MEMO) was conducted in CHCl solution using BF3 ·OEt/1, 4-butanediol as a co-initiator. The resulting copolymers were characterized by FTIR, H NMR and Gel Permeation Chromatography (GPC) analyses, and it was found that the enchained ratio of AMO in the copolymers is far lower than its feed ratio. They were crosslinked via the radical polymerization of the vinyl group initiated by BPO after doping with lithium trifluoromethanesulfonimide (LiTFSI) to give rise to tough polymeric electrolyte films. The ionic conductivity was measured at varying content of AMO and different concentration of lithium salt LiTFSI by AC impedance, and a maximum ion conductivity of 1.44×10 S/cm at 30°C or 1.25×10 S/cm at 80°C was attained in the sample PAM 33 at the mole ratio of O : Li = 20. The DSC results indicated that decreases with the increase of the proportion of AMO in the copolymer, well consistent with the ion conductivity trend. The TGA (thermogravimetric analysis) measurement revealed that this kind of copolymer electrolytes is more thermostable than their liquid counterparts.

关键词： 4-butanediol 2-methoxyethylenoxy consistent oxetane-derived copolymer

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基于玻璃通孔的Ka波段宽带滤波封装天线 Research Article

方针1,2,张继华1,2,3,高莉彬1,2,陈宏伟1,2,李文磊1,2,梁天鹏1,2,蔡旭东1,2,蔡星周3,贾惟聪3,郭欢3,李勇3

《信息与电子工程前沿（英文）》 2023年第24卷第6期页码 916-926 doi: 10.1631/FITEE.2200573

摘要： BPF单元有3对λg/4槽(缺陷微带结构)和两对λg/2 U形缝隙(缺陷地结构)。该天线实现了大带宽和高辐射效率，这可能与玻璃基板的叠加和玻璃通孔馈电有关。

关键词：滤波封装天线；玻璃通孔；三维封装器件；激光键合

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用于超导纳米线单光子探测器的宽带超低温放大器 Research Article

李连鸣1,2,何龙2,吴旭1,2,牛晓康1,万超2,康琳2,3,贾小氢2,3,张蜡宝2,3,赵清源2,3,涂学凑2,3

《信息与电子工程前沿（英文）》 2021年第22卷第12期页码 1551-1684 doi: 10.1631/FITEE.2100525

摘要：在良好输入输出阻抗匹配下，该放大器在300 K温度下3 dB带宽为1.13 GHz，增益为21 dB。在4.2 K温度下，该放大器增益可在15～24 dB范围内调节，其3 dB带宽为120 kHz～1.3 GHz，功耗仅3.1 mW。去除芯片外围焊盘，该超低温放大器芯片核心面积仅为0.073 mm2。

关键词：超低温放大器；宽带放大器；超导纳米线单光子探测器

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Microwave-assisted synthesis and antimicrobial activities of 2-aryl-3-(naphthalene-1 or 2-yl)-1,3-thiazolidin

Hua CHEN, Yanan LI, Jie BAI, Lian ZHAO, Xiangguo YUAN, Xiaoliu LI, Keqiang CAO

《化学科学与工程前沿（英文）》 2009年第3卷第2期页码 186-191 doi: 10.1007/s11705-009-0004-0

摘要： 2-aryl-3-(naphthalene-1 or 2-yl)-1,3-thiazolidin-4-ones and were synthesized in 41%-67% yield by using microwave-assisted one-pot protocol. The structures of the new compounds , , , , , , and - were confirmed by IR, NMR, MS, and elemental analysis. The antimicrobial activities of the compounds against pv. lachrymans (Smith et Bryan) Young, Dye & Wilkie, Pers., and Blum. were examined. Some of the compounds showed good antifungical activity against Blum.

关键词： microwave-assisted synthesis naphthyl thiazolidin-4-one antimicrobial

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Synthesis and fluorescence behavior of 2,5-diphenyl-1,3,4-oxadiazole-containing bismaleimides and bissuccinimides

Xin ZHANG, Zichen LI

《化学科学与工程前沿（英文）》 2013年第7卷第4期页码 381-387 doi: 10.1007/s11705-013-1359-9

摘要： Bismaleimides bearing 2,5-diphenyl-1,3,4-oxadiazole chromophores at , , position and corresponding saturated bissuccinimides were synthesized. Several synthetic strategies for these bismaleimides were discussed in detail. Almost no or very weak fluorescence was observed for these bismaleimides, however, the bissuccinimides show a strong fluorescence. The effect of molecular geometry on optical behavior and fluorescence quenching mechanism were investigated by UV-vis absorption and fluorescence emission spectroscopy. The electron coupling of ground state of -bismaleimide is stronger than those of - and -bismaleimides. -Bissuccinimide displays increasing fluorescence quantum yields with red shifts of 22–24 nm, compared to -bissuccinimide. Polymerizable C=C bonds play a key role in the intramolecular fluorescence quenching.

关键词： fluorescence bismaleimide oxadiazole succinimide

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用以产生高纯度涡旋波束的宽带圆极化透射阵 Correspondence

邱靓婕1,2,3,4,李秀萍1,2,3,4,齐紫航1,2,3,4,赵文禹1,2,3,4,黄雨菡5

《信息与电子工程前沿（英文）》 2023年第24卷第6期页码 927-934 doi: 10.1631/FITEE.2200539

摘要：测试的峰值增益为22.3 dBic，3-dB轴比带宽为27.6%。测试结果表明，本文提出的透射阵有潜力应用于高容量无线通信和高质量雷达成像方面。

关键词：轨道角动量；涡旋波束；透射阵；宽带；高纯度

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标题作者时间类型操作

Comparison study on strategies to prepare nanocrystalline Li

Qiang XIAO, Xiaodan TANG, Yefeng LIU, Yijun ZHONG, Weidong ZHU

期刊论文

Preparation and characterization of nanocrystalline ZrO2-7%Y2O3 powders for thermal barrier coatings

Kirsten BOBZIN, Lidong ZHAO, Thomas SCHLAEFER, Thomas WARDA

期刊论文

A simple and cheap method for preparation of coupled ZrO2/ZnO with high photocatalytic activities

WANG Zheng, ZHANG Bingru, LI Fengting

期刊论文

Enhanced performance of oxygen vacancies on CO adsorption and activation over different phases of ZrO

期刊论文

Visbreaking of heavy petroleum oil catalyzed by SO/ZrO solid super-acid doped with Ni or Sn

JING Ping, LI Qingbiao, HAN Mei, SUN Daohua, JIA Lishan, FANG Weiping

期刊论文

Effect of TiO 2 loading on the activity of V/TiO 2 -Al 2 O 3 in the catalytic oxidehydrogenation of ethylbenzene

Xiaohong LI, Wenying LI,

期刊论文

Preparation of Cu/ZrO

Xinmei LIU, Shaofen BAI, Huidong ZHUANG, Zifeng YAN

期刊论文

Stability of Ni/SiO

Bettina Stolze,Juliane Titus,Stephan A. Schunk,Andrian Milanov,Ekkehard Schwab,Roger Gläser

期刊论文

CO₂ methanation and co-methanation of CO and CO₂ over Mn-promoted Ni/Al₂O₃ catalysts

Kechao Zhao,Zhenhua Li,Li Bian

期刊论文

Synthesis of copolymers of 3-acryloyloxymethyl-3′-methyloxetane and 3-(2-(2-(2-Methoxyethylenoxy)ethylenoxy)ethylenoxy)-3′-methyloxetane and their ionic conductivity properties

YE Lin, ZHAO Yumei, FENG Zengguo, BAI Ying, WU Feng

期刊论文

基于玻璃通孔的Ka波段宽带滤波封装天线

方针1,2,张继华1,2,3,高莉彬1,2,陈宏伟1,2,李文磊1,2,梁天鹏1,2,蔡旭东1,2,蔡星周3,贾惟聪3,郭欢3,李勇3