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期刊论文 34

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2023 4

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关键词

Au/Ti双功能催化剂 1

H2有效利用率 1

Ni–Ti–Cu–V合金 1

Ti-V微合金钢 1

丙烯环氧化 1

中子衍射，磁相图，晶体结构 1

四元合金 1

密度泛函理论 1

封装天线（AiP），弯曲线天线，多芯片模块（MCM），低温共烧陶瓷（LTCC）， 1

封装天线；曲折线天线；多芯片组件；低温共烧陶瓷 1

属性映射 1

弹性冷却 1

形状记忆合金 1

机器学习 1

武器系统；基于过程的建模（PBM）；作战场景；交互分析；元模型；Petri网 1

热弹性冷却 1

相变 1

相间析出 1

矢量孤子；类噪声脉冲；MXene；光纤激光器 1

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Ti incorporation in MCM-41 mesoporous molecular sieves using hydrothermal synthesis

Shengping WANG, Changqing MA, Yun SHI, Xinbin MA

《化学科学与工程前沿（英文）》 2014年 第8卷 第1期   页码 95-103 doi: 10.1007/s11705-014-1405-2

摘要： Titanium-containing mesoporous materials (Ti-MCM-41) were obtained by hydrothermal synthesis. Such materials are active catalysts for the transesterification of dimethyl oxalate and phenol to produce diphenyl oxalate. To understand the role of the Ti in the catalytic process, Ti-MCM-41 samples with different Si/Ti ratios (from 5 to 100) were prepared and the samples were analyzed by Fourier transform infrared spectroscopy, UV-visible spectroscopy, and ammonia temperature programmed desorption. It was concluded that the Ti is incorporated into the framework of the MCM-41 and formed weak Lewis acid sites. In addition, the number of Ti(IV) sites increased as the amount of titanium increased. X-ray powder diffraction, N adsorption-desorption and transmission electron microscopy results showed that the Ti-MCM-41 samples have a hexagonal arrangement of mono-dimensional pores. A large number of Ti(IV) sites coupled with the mesoporous structure and large pore diameters are favorable for the transesterification catalytic properties of Ti-MCM-41.

关键词： Ti-MCM-41     mesoporous molecular sieve     acid sites     transesterification     hydrothermal synthesis    

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Enhanced CuCl dispersion by regulating acidity of MCM-41 for catalytic oxycarbonylation of ethanol to

Pengzhen CHEN, Shouying HUANG, Jijie ZHANG, Shengping WANG, Xinbin MA

《化学科学与工程前沿（英文）》 2015年 第9卷 第2期   页码 224-231 doi: 10.1007/s11705-014-1447-5

摘要： CuCl supported on molecular sieves has attracted increasing attention in catalyzing oxidative carbonylation of ethanol to diethyl carbonate. Mesoporous MCM-41 has been widely used as catalyst support due to its large surface area and well defined mesoporous structure. Considering its intrinsic weak acidity, MCM-41 was modified by a simple impregnation method to incorporate Al. The incorporation of Al components resulted in the high dispersion of Cu species and the increase of acid sites without changing the mesoporous structure of MCM-41, and thus enhanceed the catalytic activity of CuCl/MCM-41for diethyl carbonate synthesis.

关键词： MCM-41     acidity     oxidative carbonylation     diethyl carbonate    

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Synthesis of nanofluids composed of deep eutectic solvents and metal-modified MCM-41 particles as multifunctional

《化学科学与工程前沿（英文）》 2023年 第17卷 第11期   页码 1776-1787 doi: 10.1007/s11705-023-2314-z

摘要： Compared with traditional hydrodesulfurization, new nonhydrodesulfurization methods have the advantage of a high removal efficiency for thiophene compounds under mild conditions. However, independent nonhydrodesulfurization technologies are faced with their own shortcomings, such as limitations of the desulfurization performance and regeneration of materials. To overcome these limitations, four nanofluids were prepared by dispersing different metal-modified MCM-41 particles in deep eutectic solvent as multifunctional promoters to develop a comprehensive desulfurization method. Based on the excellent adsorbability and high catalytic activity of the dispersed particles and the outstanding extractability of deep eutectic solvent in nanofluids, a high sulfur removal of 99.33% was achieved for model oil under mild conditions in 15 min. The nanofluids also showed excellent reusability due to their high structural stability. In addition, NF@Cu/Al-MCM-41-2.5% exhibited the best desulfurization performance among the prepared nanofluids. This result was obtained because the introduction of Al ions increased the number of acid sites and defect sites to improve the catalytic activity and adsorbability, and the best affinity of Cu/Al-MCM-41 for the deep eutectic solvent favored the reaction mass transfer. This work opens the door to the development of a comprehensive nonhydrodesulfurization method based on the design of nanofluid materials.

关键词： fuel oil desulfurization     nanofluids     catalytic ozonation    

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Atomistic simulations for adsorption and separation of flue gas in MFI zeolite and MFI/MCM-41 micro/mesoporous

Shengchi ZHUO, Yongmin HUANG, Jun HU, Honglai LIU

《化学科学与工程前沿（英文）》 2011年 第5卷 第2期   页码 264-273 doi: 10.1007/s11705-010-1007-6

摘要： Adsorption of pure CO and N and separation of CO /N mixture in MFI zeolite and MFI/MCM-41 micro/mesoporous composite have been studied by using atomistic simulations. Fully atomistic models of MFI and MFI/MCM-41 are constructed and characterized. A bimodal pore size distribution is observed in MFI/MCM-41 from simulated small- and broad-angle X-ray diffraction patterns. The density of MFI/MCM-41 is lower than MFI, while its free volume and specific surface area are greater than MFI due to the presence of mesopores. CO is preferentially adsorbed than N , and thus, the loading and isosteric heat of CO are greater than N in both MFI and MFI/MCM-41. CO isotherm in MFI/MCM-41 is similar to that in MFI at low pressures, but resembles that in MCM-41 at high pressures. N shows similar amount of loading in MFI, MCM-41 and MFI/MCM-41. The selectivity of CO over N in the three adsorbents decreases in the order of MFI>MFI/MCM-41>MCM-41. With increasing pressure, the selectivity increases in MFI and MFI/MCM-41, but decreases in MCM-41. The self-diffusivity of CO and N in MFI decreases as loading increases, while in MFI/MCM-41, it first increases and then drops.

关键词： adsorption     diffusion     CO2     flue gas     zeolite     micro/mesoporous composite    

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Preparation of TiO

Shenghung WANG, Kuohua WANG, Jihmirn JEHNG, Lichen LIU

《环境科学与工程前沿（英文）》 2012年 第6卷 第3期   页码 304-312 doi: 10.1007/s11783-010-0297-8

摘要： Titanium dioxide is coated on the surface of MCM-41 wafer through the plasma enhanced chemical vapor deposition (PECVD) method using titanium isopropoxide (TTIP) as a precursor. Annealing temperature is a key factor affecting crystal phase of titanium dioxide. It will transform an amorphous structure to a polycrystalline structure by increasing temperature. The optimum anatase phase of TiO which can acquire the best methanol conversion under UV-light irradiation is obtained under an annealing temperature of 700°C for 2 h, substrate temperature of 500°C, 70 mL·min of oxygen flow rate, and 100 W of plasma power. In addition, the films are composed of an anatase-rutile mixed phase, and the ratio of anatase to rutile varies with substrate temperature and oxygen flow rate. The particle sizes of titanium dioxide are between 30.3 nm and 59.9 nm by the calculation of Scherrer equation. Under the reaction conditions of 116.8 mg·L methanol, 2.9 mg·L moisture, and 75°C of reaction temperature, the best conversion of methanol with UV-light is 48.2% by using the anatase-rutile (91.3/8.7) mixed phase TiO in a batch reactor for 60 min. While under fluorescent light irradiation, the best photoactivity appears by using the anatase-rutile (55.4/44.6) mixed phase TiO with a conversion of 40.0%.

关键词： photocatalyst     titanium dioxide     MCM-41     plasma enhanced chemical vapor deposition (PECVD)    

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Synthesis, characterization and catalytic properties of mesoporous MCM-48 containing zeolite secondary

LI Qiang, ZHANG Ying, DOU Tao, LI Yuping, WANG Shan, SUN Famin

《化学科学与工程前沿（英文）》 2007年 第1卷 第1期   页码 1-5 doi: 10.1007/s11705-007-0001-0

摘要： Mesoporous aluminosilicate MCM-48 containing zeolite secondary building units in the pore wall has been synthesized in alkaline media with a two-step procedure. The aluminosilicate precursors comprising zeolite secondary building units were first synthesized by carefully controlling reaction conditions and then were assembled using cotemplates of gemini surfactant [CHN(CH)(CH)N(CH)CH] (18-3-18) and triethanolamine (TEA). X-ray Diffraction (XRD) patterns of the as-made samples indicated that highly ordered mesostructured MCM-48 was formed. Transmission Electron Microscopy (TEM) images further verified the formation of MCM-48 with uniform cubic pore channel system having the pore opening diameter of about 25 Å. Compared with the conventionally synthesized MCM-48, the as-synthesized MCM-48 sample showed an adsorption band at 520 600 cm in its FT-IR spectrum, which was assigned to five-membered ring vibration from zeolite structure. This suggested the presence of zeolite building units in the pore wall. N2 adsorption data showed that the material had a much higher specific surface area (1 200 m/g) than the conventional MCM-48(1 100 m/g). Finally, the catalytic performance of the as-made MCM-48 was evaluated by hydrogenation dealkylation reaction of heavy aromatic hydrocarbons. Catalytic results showed that the as-made MCM-48 catalyst exhibited higher conversion than the conventional MCM-48 catalyst. The as-made mesostructured MCM-48 may have a potential catalytic application in the conversion of bulky molecules.

关键词： diameter     mesostructured MCM-48     Catalytic     presence     five-membered    

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Fabrication and in vivo evaluation of Ti6Al4V implants with controlled porous structure and complex shape

Xiang LI, Yun LUO, Chengtao WANG, Wenguang ZHANG, Yuanchao LI

《机械工程前沿（英文）》 2012年 第7卷 第1期   页码 66-71 doi: 10.1007/s11465-012-0302-y

摘要：

Electron beam melting process was used to fabricate porous Ti6Al4V implants. The porous structure and surface topography of the implants were characterized by scanning electron microscopy (SEM) and digital microscopy (DM). The results showed that the pore size was around 600 and the porosity approximated to 57%. There was about±50 μm of undulation on implants surfaces. Standard implants and a custom implant coupled with porous sections were designed and fabricated to validate the versatility of the electron beam melting (EBM) technique. After coated with bone-like apatite, samples with fully porous structures were implanted into cranial defects in rabbits to investigate the in vivo performance. The animals were sacrificed at 8 and 12 weeks after implantation. Bone ingrowth into porous structure was examined by histological analysis. The histological sections indicated that a large amount of new bone formation was observed in porous structure. The newly formed bone grew from the calvarial margins toward the center of the bone defect and was in close contact with implant surfaces. The results of the study showed that the EBM produced Ti6Al4V implants with well-controlled porous structure, rough surface topography and bone-like apatite layer are beneficial for bone ingrowth and apposition.

关键词： electron beam melting process     implant     porous structure     bone ingrowth    

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Zinc modification of Ni-Ti as efficient NiZnTi catalysts with both geometric and electronic improvements

《化学科学与工程前沿（英文）》 2022年 第16卷 第4期   页码 461-474 doi: 10.1007/s11705-021-2072-8

摘要： The catalytic hydrogenation of nitroaromatics is an environmentally friendly technology for aniline production, and it is crucial to develop noble-metal-free catalysts that can achieve chemoselective hydrogenation of nitroaromatics under mild reaction conditions. In this work, zinc-modified Ni-Ti catalysts (NixZnyTi1) were fabricated and applied for the hydrogenation of nitroaromatics hydrogenation. It was found that the introduction of zinc effectively increases the surface Ni density, enhances the electronic effect, and improves the interaction between Ni and TiO2, resulting in smaller Ni particle size, more oxygen vacancies, higher dispersion and greater concentration of Ni on the catalyst surface. Furthermore, the electron-rich Niδ– obtained by electron transfer from Zn and Ti to Ni effectively adsorbs and dissociates hydrogen. The results reveal that NixZnyTi1 (Ni0.5Zn0.5Ti1) shows excellent catalytic performance under mild conditions (70 °C and 6 bar). These findings provide a rational strategy for the development of highly active non-noble-metal hydrogenation catalysts.

关键词： bimetal strategy     oxygen vacancy     non-noble metal catalyst     hydrogenation     aromatic nitro compounds    

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The synergic effects of highly selective bimetallic Pt-Pd/SAPO-41 catalysts for the

Guozhi Jia, Chunmu Guo, Wei Wang, Xuefeng Bai, Xiaomeng Wei, Xiaofang Su, Tong Li, Linfei Xiao, Wei Wu

《化学科学与工程前沿（英文）》 2021年 第15卷 第5期   页码 1111-1124 doi: 10.1007/s11705-020-2031-9

摘要： The hydroisomerization of -hexadecane over Pt-Pd bimetallic catalysts is an effective way to produce clean fuel oil. This work reports a useful preparation method of bimetallic bifunctional catalysts by a co-impregnation or sequential impregnation process. Furthermore, monometallic catalysts with loading either Pt or Pd are also prepared for comparison. The effects of the metal species and impregnation order on the characteristics and catalytic performance of the catalysts are investigated. The catalytic test results indicate that the maximum -hexadecane yield over different catalysts increases as follows: Pt/silicoaluminophosphate SAPO-41

关键词： SAPO-41 molecular sieve     Pt-Pd bimetallic site     bifunctional catalysts     n-hexadecane     hydroisomerization    

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配位不饱和Au-O-Ti3+活性位点的构建及其在低温丙烯气相环氧化反应中强化氢气效率的研究 Article

宋钊宁, 闫昊, 袁俊聪, 马宏飞, 曹建琳, 王永祥, 王强, 彭冲, 邓风, 冯翔, 陈德, 杨朝合, 胡永康

《工程（英文）》 2023年 第25卷 第6期   页码 144-156 doi: 10.1016/j.eng.2023.01.008

摘要：

自1998年以来，人们广泛认为Au/Ti基催化剂的Au-O-Ti4+位点是在相对高温条件下丙烯气相环氧化反应的活性位点，但该类催化剂的H2有效利用率普遍较低本工作发现了一种在相对低温条件下丙烯气相环氧化反应的新活性位点Au-O-Ti3+。并且利用原位紫外-可见光谱（operando UV-vis）技术研究了Ti-OOH反应中间体的动态演化过程，结果表明，在Au-O-Ti3+活性位点上的Ti-OOH的生成速率比在Au-O-TiTi3+位点促进了Au和Ti3+之间的电子转移，从而增强了催化剂对O2的吸附能力，有效促进H2O2的原位生成，并进一步促进活性中间体Ti-OOH的形成。

关键词： 丙烯环氧化     H2有效利用率     Au/Ti双功能催化剂     配位不饱和Ti位点     密度泛函理论    

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基于LTCC技术与曲折线天线集成的封装天线系统

Gang DONG,Wei XIONG,Zhao-yao WU,Yin-tang YANG

《信息与电子工程前沿（英文）》 2016年 第17卷 第1期   页码 67-73

摘要： 该系统采用曲折线贴片天线，封装层和层压多芯片模块（MCM）来集成集成电路（IC）裸芯片。微带馈线用于减少贴片和封装之间的相互作用。为了减少电磁耦合，设计并分析了通孔结构。

关键词： 封装天线（AiP），弯曲线天线，多芯片模块（MCM），低温共烧陶瓷（LTCC），    

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Effects of Boundary Condition and Helix Angle on Meshing Performance of TI Worm Gearing

SUN Yue-hai, DUAN Lu-qian, WANG Shu-ren, ZHANG Ce

《机械工程前沿（英文）》 2006年 第1卷 第1期   页码 90-95 doi: 10.1007/s11465-005-0006-7

摘要：

To exactly describe the contact state and contact area of tooth surface of toroidal involute (TI) worm gearing, the authors introduced boundary condition into contact line analysis.With helix angle chosen as parameter, the criterion for the existence of meshing boundary line on the surface of TI worm gearing is derived. Results show that there can be four situations for meshing boundary line on the tooth surface of gear, namely, inexistence of meshing boundary line, a unique line, two lines, and two coincident lines. If the helix angle is equal to or slightly smaller than the bigger angle, which makes two meshing boundary lines superpose, a preferable meshing performance is obtained. Computer simulation proves the validity of the above conclusion.

关键词： preferable     inexistence     Results     validity     boundary condition    

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Facile controlled synthesis of hierarchically structured mesoporous Li4Ti5O12/C/rGO composites as high-performance

Cehuang FU, Shuiyun SHEN, Ruofei WU, Xiaohui YAN, Guofeng XIA, Junliang ZHANG

《能源前沿（英文）》 2022年 第16卷 第4期   页码 607-612 doi: 10.1007/s11708-021-0798-0

摘要： In this paper, a facile strategy is proposed to controllably synthesize mesoporous Li4Ti5O12/C nanocomposite embedded in graphene matrix as lithium-ion battery anode via the co-assembly of Li4Ti5O12 (LTO) precursor, GO, and phenolic resin. The obtained composites, which consists of a LTO core, a phenolic-resin-based carbon shell, and a porous frame constructed by rGO, can be denoted as LTO/C/rGO and presents a hierarchical structure. Owing to the advantages of the hierarchical structure, including a high surface area and a high electric conductivity, the mesoporous LTO/C/rGO composite exhibits a greatly improved rate capability as the anode material in contrast to the conventional LTO electrode.

关键词： Li4Ti5O12     phenolic-resin-based carbon     mesoporous composite     graphene    

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DyFe11Ti磁结构及其自旋重取向的中子衍射研究 Article

Olivier Isnard, Eder J. Kinast

《工程（英文）》 2020年 第6卷 第2期   页码 153-157 doi: 10.1016/j.eng.2019.11.009

摘要：

本文报道了通过中子粉末衍射探测DyFe11Ti的磁结构及其热演化规律。使用了变温中子衍射技术来测量磁矩及其取向的温度依赖性。

关键词： 中子衍射，磁相图，晶体结构    

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Robust optimization of the billet for isothermal local loading transitional region of a Ti-alloy rib-web

Ke WEI, Xiaoguang FAN, Mei ZHAN, Miao MENG

《机械工程前沿（英文）》 2018年 第13卷 第3期   页码 376-384 doi: 10.1007/s11465-018-0500-3

摘要：

Billet optimization can greatly improve the forming quality of the transitional region in the isothermal local loading forming (ILLF) of large-scale Ti-alloy rib-web components. However, the final quality of the transitional region may be deteriorated by uncontrollable factors, such as the manufacturing tolerance of the preforming billet, fluctuation of the stroke length, and friction factor. Thus, a dual-response surface method (RSM)-based robust optimization of the billet was proposed to address the uncontrollable factors in transitional region of the ILLF. Given that the die underfilling and folding defect are two key factors that influence the forming quality of the transitional region, minimizing the mean and standard deviation of the die underfilling rate and avoiding folding defect were defined as the objective function and constraint condition in robust optimization. Then, the cross array design was constructed, a dual-RSM model was established for the mean and standard deviation of the die underfilling rate by considering the size parameters of the billet and uncontrollable factors. Subsequently, an optimum solution was derived to achieve the robust optimization of the billet. A case study on robust optimization was conducted. Good results were attained for improving the die filling and avoiding folding defect, suggesting that the robust optimization of the billet in the transitional region of the ILLF was efficient and reliable.

关键词： isothermal local loading forming     rib-web component     transitional region     robust optimization     dual response surface method    

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标题 作者 时间 类型 操作

Ti incorporation in MCM-41 mesoporous molecular sieves using hydrothermal synthesis

Shengping WANG, Changqing MA, Yun SHI, Xinbin MA

期刊论文

Enhanced CuCl dispersion by regulating acidity of MCM-41 for catalytic oxycarbonylation of ethanol to

Pengzhen CHEN, Shouying HUANG, Jijie ZHANG, Shengping WANG, Xinbin MA

期刊论文

Synthesis of nanofluids composed of deep eutectic solvents and metal-modified MCM-41 particles as multifunctional

期刊论文

Atomistic simulations for adsorption and separation of flue gas in MFI zeolite and MFI/MCM-41 micro/mesoporous

Shengchi ZHUO, Yongmin HUANG, Jun HU, Honglai LIU

期刊论文

Preparation of TiO

Shenghung WANG, Kuohua WANG, Jihmirn JEHNG, Lichen LIU

期刊论文

Synthesis, characterization and catalytic properties of mesoporous MCM-48 containing zeolite secondary

LI Qiang, ZHANG Ying, DOU Tao, LI Yuping, WANG Shan, SUN Famin

期刊论文

Fabrication and in vivo evaluation of Ti6Al4V implants with controlled porous structure and complex shape

Xiang LI, Yun LUO, Chengtao WANG, Wenguang ZHANG, Yuanchao LI

期刊论文

Zinc modification of Ni-Ti as efficient NiZnTi catalysts with both geometric and electronic improvements

期刊论文

The synergic effects of highly selective bimetallic Pt-Pd/SAPO-41 catalysts for the

Guozhi Jia, Chunmu Guo, Wei Wang, Xuefeng Bai, Xiaomeng Wei, Xiaofang Su, Tong Li, Linfei Xiao, Wei Wu

期刊论文

配位不饱和Au-O-Ti3+活性位点的构建及其在低温丙烯气相环氧化反应中强化氢气效率的研究

宋钊宁, 闫昊, 袁俊聪, 马宏飞, 曹建琳, 王永祥, 王强, 彭冲, 邓风, 冯翔, 陈德, 杨朝合, 胡永康

期刊论文

基于LTCC技术与曲折线天线集成的封装天线系统

Gang DONG,Wei XIONG,Zhao-yao WU,Yin-tang YANG

期刊论文

Effects of Boundary Condition and Helix Angle on Meshing Performance of TI Worm Gearing

SUN Yue-hai, DUAN Lu-qian, WANG Shu-ren, ZHANG Ce

期刊论文

Facile controlled synthesis of hierarchically structured mesoporous Li4Ti5O12/C/rGO composites as high-performance

Cehuang FU, Shuiyun SHEN, Ruofei WU, Xiaohui YAN, Guofeng XIA, Junliang ZHANG

期刊论文

DyFe11Ti磁结构及其自旋重取向的中子衍射研究

Olivier Isnard, Eder J. Kinast

期刊论文

Robust optimization of the billet for isothermal local loading transitional region of a Ti-alloy rib-web

Ke WEI, Xiaoguang FAN, Mei ZHAN, Miao MENG

期刊论文