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Effect of sodium ions in synthesis of titanium silicalite-1 on its catalytic performance for cyclohexanone ammoximation

Pengxu YAO,Yaquan WANG,Teng ZHANG,Shuhai WANG,Xiaoxue WU

《化学科学与工程前沿（英文）》 2014年 第8卷 第2期   页码 149-155 doi: 10.1007/s11705-014-1409-y

摘要： Titanium silicalite-1 (TS-1) has been hydrothermally synthesized with tetrapropylammonium hydroxide (TPAOH) as the template in the presence of various amounts of Na , characterized by inductively coupled plasma, X-ray diffraction, scanning electron microscope, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy and ultro-violet-visible spectroscopy and studied in cyclohexanone ammoximation. The characterization results show that with the increase of Na concentration in the synthesis, both the crystal sizes of TS-1and extra framework Ti increase but framework Ti decreases. The addition of Na below 3 mol-% of TPAOH in the synthesis does not influence the catalytic properties with above 98% conversion of cyclohexanone and 99.5% selectivity to cyclohexanone oxime. However, at the concentrations of Na ≥3 mol-% of TPAOH in the synthesis, the catalysts are deactivated faster with the increase of Na addition, which can be attributed to more high molecular weight byproducts deposited in the large TS-1 particles and the loss of the frame-work titanium. The results of this work are of great importance for the industry.

关键词： extra framework Ti     cyclohexanone ammoximation     titanium silicalite-1     sodium ion     crystal size    

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Management and operation of extra-large Fangcang hospitals: experience and lessons from containing the

《医学前沿（英文）》 2023年 第17卷 第1期   页码 165-171 doi: 10.1007/s11684-022-0961-y

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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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Demonstration project of safe and efficient mining operations in extra-thick coal seam

Jinhui WANG

《工程管理前沿（英文）》 2017年 第4卷 第1期   页码 110-110 doi: 10.15302/J-FEM-2016063

摘要：
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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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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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Efficiency measurement for mixed two-stage nonhomogeneous network processes with shared extra intermediate

Qingxian AN, Xuyang LIU, Shijie DING

《工程管理前沿（英文）》 2020年 第7卷 第2期   页码 259-274 doi: 10.1007/s42524-019-0080-x

摘要： Unreasonable allocation of shared resources reduces the system efficiency and is a considerable operational risk. Sub-processes with insufficient portion of shared resources could not help accomplish complicated tasks, and overstaffing and idle resources will occur in the sub-processes assigned with redundant shared resources. This unfair portion distribution may cause internal contradictions among sub-processes and even lead to the collapsing of the entire system. This study proposes a data-driven, mixed two-stage network data envelopment analysis model. This method aims to reasonably define the allocation portion of shared extra intermediate resources among several nonhomogeneous subsystems and measure the overall system performance. A data set of 58 international hotels is used to test the features of the proposed model.

关键词： shared resource allocation     mixed two-stage system     data envelopment analysis     efficiency    

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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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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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Ni-Ti-Cu-V四元薄膜库中微观结构和相变的组合合成和高通量表征 Article

Naila M. Al Hasan, Huilong Hou, Suchismita Sarkar, Sigurd Thienhaus, Apurva Mehta, Alfred Ludwig, Ichiro Takeuchi

《工程（英文）》 2020年 第6卷 第6期   页码 637-643 doi: 10.1016/j.eng.2020.05.003

摘要：

过去70年来，基于Ni-Ti的形状记忆合金（shape memory alloy, SMA）已得到广泛使用，但是提高 其功能稳定性仍然是实现更稳健和更高级应用的关键。

关键词： Ni–Ti–Cu–V合金     组合材料科学     四元合金     形状记忆合金     薄膜库     弹性冷却     热弹性冷却     相变     高通量表征     属性映射     机器学习    

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鄂尔多斯盆地特低渗透砂岩储层裂缝压力敏感性及其开发意义

曾联波,史成恩,王永康,李书恒,万晓龙,崔攀峰

《中国工程科学》 2007年 第9卷 第11期   页码 35-38

摘要：

为了分析特低渗透砂岩储层高角度裂缝的压力敏感性特征，对鄂尔多斯盆地陇东地区延长组特低渗透砂岩储层基质岩样、含天然裂缝岩样和含人造裂缝岩样进行了对比实验。实验结果表明，特低渗透砂岩储层裂缝的压力敏感性十分明显,在无裂缝时基质岩块为中等程度敏感性，含裂缝时为强压力敏感性。裂缝的开度越大，渗透率越高，其压力敏感性越强，裂缝渗透率的恢复程度越小。裂缝的压力敏感性特征对特低渗透砂岩油藏开发具有十分重要的意义。

关键词： 裂缝     压力敏感性     开发意义     特低渗透砂岩储层     鄂尔多斯盆地    

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Excellent performance of Cu-Mn/Ti-sepiolite catalysts for low-temperature CO oxidation

Yong Song,Lisha Liu,Zhidan Fu,Qing Ye,Shuiyuan Cheng,Tianfang Kang,Hongxing Dai

《环境科学与工程前沿（英文）》 2017年 第11卷 第2期 doi: 10.1007/s11783-017-0908-8

摘要： Sepiolite is clay mineral with a 2:1 layered structure. Ti-pillars have an impact on physicochemical property of the sample. 30Mn5Cu/Ti-Sep shows excellent catalytic activity for the oxidation of CO. The interaction, reducibility, and oxygen mobility govern the activity. The Ti-modified sepiolite (Ti-Sep)-supported Mn-Cu mixed oxide ( Mn5Cu/Ti-Sep) catalysts were synthesized using the co-precipitation method. The materials were characterized by the X-ray diffraction scanning electron microscope, N adsorption-desorption, H -TPR, O -TPD, and XPS techniques, and their catalytic activities for CO oxidation were evaluated. It was found that the catalytic activities of Mn5Cu/Ti-Sep were higher than those of 5Cu/Ti-Sep and 30Mn/Ti-Sep, and the Mn/Cu molar ratio had a distinct influence on catalytic activity of the sample. Among the Mn5Cu/Ti-Sep samples, the 30Mn5Cu/Ti-Sep catalyst showed the best activity (which also outperformed the 30Mn5Cu/Sep catalyst), giving the highest reaction rate of 0.875 × 10 mmol·g ·s and the lowest and of 56°C and 86°C, respectively. Moreover, the 30Mn5Cu/Ti-Sep possessed the best low-temperature reducibility, the lowest O desorption temperature, and the highest surface Mn /Mn atomic ratio. It is concluded that factors, such as the strong interaction between the copper or manganese oxides and the Ti-Sep support, good low-temperature reducibility, and good mobility of chemisorbed oxygen species, were responsible for the excellent catalytic activity of 30Mn5Cu/Ti-Sep.

关键词： Ti-modified sepiolite     Supported Mn-Cu mixed oxide     Low-temperature reducibility     Strong metal-support interaction     CO oxidation    

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标题 作者 时间 类型 操作

Effect of sodium ions in synthesis of titanium silicalite-1 on its catalytic performance for cyclohexanone ammoximation

Pengxu YAO,Yaquan WANG,Teng ZHANG,Shuhai WANG,Xiaoxue WU

期刊论文

Management and operation of extra-large Fangcang hospitals: experience and lessons from containing the

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

Demonstration project of safe and efficient mining operations in extra-thick coal seam

Jinhui WANG

期刊论文

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

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

Efficiency measurement for mixed two-stage nonhomogeneous network processes with shared extra intermediate

Qingxian AN, Xuyang LIU, Shijie DING

期刊论文

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

Shengping WANG, Changqing MA, Yun SHI, Xinbin MA

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

Ni-Ti-Cu-V四元薄膜库中微观结构和相变的组合合成和高通量表征

Naila M. Al Hasan, Huilong Hou, Suchismita Sarkar, Sigurd Thienhaus, Apurva Mehta, Alfred Ludwig, Ichiro Takeuchi

期刊论文

鄂尔多斯盆地特低渗透砂岩储层裂缝压力敏感性及其开发意义

曾联波,史成恩,王永康,李书恒,万晓龙,崔攀峰

期刊论文

Excellent performance of Cu-Mn/Ti-sepiolite catalysts for low-temperature CO oxidation

Yong Song,Lisha Liu,Zhidan Fu,Qing Ye,Shuiyuan Cheng,Tianfang Kang,Hongxing Dai

期刊论文