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医院中子照射器I型堆 5

GM(1 4

1)模型 2

MCNP 2

中子通量密度 2

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医院中子照射器 2

无氢渗碳 2

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环境一号卫星 2

(GaxIn1−x)2O3薄膜；带隙可调谐；磁控溅射 1

1 1

1) 1

1)幂模型 1

1860 MPa等级 1

1T/2H-MoS₂ 1

2R-1C模型；嵌入式系统；参数估计；非迭代方法；二次型 1

4250 m 1

5-戊二胺 1

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Effect of triethylamine treatment of titanium silicalite-1 on propylene epoxidation

Juan XU,Yaquan WANG,Wenping FENG,Yi LIN,Shuhai WANG

《化学科学与工程前沿（英文）》 2014年第8卷第4期页码 478-487 doi: 10.1007/s11705-014-1453-7

摘要： Titanium silicalite-1(TS-1) treated with triethylamine (TEA) solution under different conditions was characterized by X-ray powder diffraction (XRD), Fourier-transform infrared spectrum (FTIR), ultraviolet-visible diffuse reflectance spectrum (UV-Vis), nitrogen physical adsorption and desorption, scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The characterization results show that many irregular hollows are generated in the TS-1 crystals due to the random dissolution of framework silicon and the volume of the hollow cavities increase with increasing the TEA concentration, and the treatment temperature and time. The modified TS-1 samples improved in varying degrees the catalyst life for the epoxidation of propylene in a fixed-bed reactor probably due to the generation of the hollows to make it easy for the reactants and products to diffuse out of the channels.

关键词： titanium silicalite-1 triethylamine hollow cavity epoxidation of propylene catalyst life

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

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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affecting the formation of zeolite seed layers and the effects of seed layers on the growth of zeolite silicalite-1-1 membranes

ZHANG Xiongfu, WANG Jinqu, LIU Hai′ou, WANG Anjie

《化学科学与工程前沿（英文）》 2007年第1卷第2期页码 172-177 doi: 10.1007/s11705-007-0032-6

摘要： The present study investigates the formation of silicalite-1 seed layers on a porous carbon support of 0.5 μm pore size and α-A1O supports with different pore sizes (0.1 μm and 4 μm) via the slip-casting technique. The effects of support property, seed size and solvent on the formation of seed layers were investigated in detail. The growth of silicalite-1 membranes on different seeded supports by hydrothermal synthesis was also evaluated. The scanning electron microscopy (SEM) and X-ray diffraction (XRD) characterizations indicate that a continuous seed layer can be obtained on the smooth support of 0.1 μm pore size by using any seed of 100 nm, 600 nm or 2.2 μm in size, whereas, on the coarse supports with either 0.5 μm or 4 μm pore size, a continuous seed layer cannot be formed using the above seed sizes and the same seeding time. At a longer contact time, a seed layer can also be formed using 100 nm seed on the supports with larger pore size. However, the layer is not uniform and smooth. For a hydrophobic porous carbon support, seeding ethanol suspension, which has weak polarity, favors the formation of a continuous seed layer. The seed layers and membranes grown from the smaller seed are more uniform and continuous and possess smoother surfaces than those from the larger seed. The seed layer and respective grown membrane formed from nanosized seed (100 nm) are the most uniform and compact. With this method of seeded secondary synthesis of zeolite membranes, the quality of a membrane mainly depends on the quality of the seed layer.

关键词： silicalite-1 α-A1O growth seeding ethanol quality

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Copolymerization of 1-butene and 1-hexene with supported titanium catalyst

ZHAO Yongxian, SHAO Huafeng, WANG Bo, YAO Wei, HUANG Baochen

《化学科学与工程前沿（英文）》 2007年第1卷第3期页码 304-309 doi: 10.1007/s11705-007-0056-y

摘要： With TiCl/MgCl (Ti) and Al(-Bu) (Al) as catalysts, the thermoplastic copolymer of 1-butene(Bt) and 1-hexene(He) was synthesized successfully. The effects of Bt/He, Ti/(He+Bt), Al/Ti, temperature and reaction time on conversion, catalyst efficiency(CE), intrinsic viscosity([η]) and insoluble content were studied. The copolymer was analyzed with Fourier transform-infrared (FTIR) and nuclear magnetic resonance (H-NMR). Results showed that the optimal polymerization conditions were: He/Bt = 0.25, temperature 40ºC–50ºC, Al/Ti = 400–500, Ti/(Bt+He) = 3×10-4*times;10, time 4 h. Intrinsic viscosity was found to increase with increasing Ti/(Bt+He) and decreasing Al/Ti and polymerization temperature. When the molar content of He, Al/Ti and polymerization temperature increased, the insoluble content in CHCl of copolymers decreased. When Ti/(Bt+He) and reaction time increased, the insoluble content in CHCl of copolymers also increased. The crystallization and stereoregularity of poly(1-butene) decreased with the addition of He.

关键词： reaction conversion temperature polymerization temperature magnetic resonance

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Influence of Na

Rumin YANG, Fanhui MENG, Xiao WANG, Yaquan WANG

《化学科学与工程前沿（英文）》 2011年第5卷第4期页码 401-408 doi: 10.1007/s11705-011-1129-5

摘要： Silicalite-1 was hydrothermally synthesized in the presence of different concentrations of Na using tetrapropylammonium hydroxide (TPAOH) as a template. The synthesis was followed by a base treatment. The silicalite-1samples were characterized using X-ray diffraction, scanning electron microscopy, N adsorption, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy and NH temperature-programmed desorption. The samples were used as catalysts for the vapor phase Beckmann rearrangement of cyclohexanone oxime. During the synthesis, the sodium ions were incorporated onto the silicalite-1 crystals, but were then removed by the base treatment. All the catalysts exhibited nearly complete conversion of cyclohexanone oxime to ?-caprolactam with selectivities grater than 95%. Addition of less than 2.5 mol-% Na (relative to TPAOH) did not influence the catalytic properties. However, for Na concentrations≥5 mol-%, the particle sizes of silicalite-1 increased and the catalytic activities decreased, which can be attributed to carbon deposition. The results in this work are of great importance for the polymer industry.

关键词： silicalite-1 cyclohexanone oxime vapor phase Beckmann rearrangement ?-caprolactam

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Anodization of titanium alloys for orthopedic applications

Merve İzmir, Batur Ercan

《化学科学与工程前沿（英文）》 2019年第13卷第1期页码 28-45 doi: 10.1007/s11705-018-1759-y

摘要：

In recent years, nanostructured oxide films on titanium alloy surfaces have gained significant interest due to their electrical, catalytic and biological properties. In literature, there is variety of different approaches to fabricate nanostructured oxide films. Among these methods, anodization technique, which allows fine-tuning of oxide film thickness, feature size, topography and chemistry, is one of the most popular approaches to fabricate nanostructured oxide films on titanium alloys, and it has been widely investigated for orthopedic applications. Briefly, anodization is the growth of a controlled oxide film on a metallic component attached to the anode of an electrochemical cell. This review provides an overview of the anodization technique to grow nanostructured oxide films on titanium and titanium alloys and summarizes the interactions between anodized titanium alloy surfaces with cells in terms of cellular adhesion, proliferation and differentiation. It will start with summarizing the mechanism of nanofeatured oxide fabrication on titanium alloys and then switch its focus on the latest findings for anodization of titanium alloys, including the use of fluoride free electrolytes and anodization of 3D titanium foams. The review will also highlight areas requiring further research to successfully translate anodized titanium alloys to clinics for orthopedic applications.

关键词： titanium alloys anodization biocompatibility orthopedics

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钛——跨入新千年的金属巨人

杨遇春

《中国工程科学》 2002年第4卷第3期页码 21-31

摘要：

介绍了海绵钛提取及钛材生产在20世纪的兴起与发展；论述了钛、钛材、钛合金在国民经济各主要工业部门，特别是在高新技术领域的广泛应用与重要作用；展望了钛工业在新千年的市场前景并提出在我国应给予重点发展和关注的建议。

关键词：钛海绵钛钛材钛工业钛的市场供求

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钛在汽车工业中的应用及降低钛材成本的工艺

杨遇春

《中国工程科学》 2005年第7卷第8期页码 9-17

摘要：

叙述了钛在减轻汽车自重、节约燃油、保护环境、降低噪声、提高汽车性能方面的优势和应用领域及趋势。介绍并评价了几种降低海绵钛与钛材成本的工艺技术。

关键词：钛汽车用钛材钛冶金新工艺

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Removal of fluoride from water using titanium-based adsorbents

Zhijian LI, Shubo DENG, Xueying ZHANG, Wei ZHOU, Jun HUANG, Gang YU

《环境科学与工程前沿（英文）》 2010年第4卷第4期页码 414-420 doi: 10.1007/s11783-010-0241-y

摘要： Three adsorbents including TiO , Ti-Ce, and Ti-La hybrid oxides were prepared to remove fluoride from aqueous solution. The Ti-Ce and Ti-La hybrid adsorbents obtained by the hydrolysis-precipitation method had much higher sorption capacity for fluoride than the TiO adsorbent prepared through hydrolysis. Rare earth (Ce and La) oxides and TiO exhibited a synergistic effect in the hybrid adsorbents for fluoride sorption. The sorption equilibrium of fluoride on the three adsorbents was achieved within 4 h, and the pseudo-second-order model described the sorption kinetics well. The sorption isotherms fitted the Langmuir model well, and the adsorption capacities of fluoride on the Ti-Ce and Ti-La adsorbents were about 9.6 and 15.1 mg·g , respectively, at the equilibrium fluoride concentration of 1.0 mg·L , much higher than the 1.7 mg·g on the TiO . The sorption capacities of fluoride on the three adsorbents decreased significantly when the solution pH increased from 3 to 9.5. The electrostatic interaction played an important role in fluoride removal by the three adsorbents, and Fourier transform infrared (FTIR) analysis indicated that the hydroxyl groups on the adsorbent surface were involved in fluoride adsorption.

关键词： fluoride adsorption titanium dioxide titanium-based adsorbent sorption mechanism

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Photocatalytic reduction of carbon dioxide by titanium oxide-based semiconductors to produce fuels

Xi CHEN, Fangming JIN

《能源前沿（英文）》 2019年第13卷第2期页码 207-220 doi: 10.1007/s11708-019-0628-9

摘要： To tackle the crisis of global warming, it is imperative to control and mitigate the atmospheric carbon dioxide level. Photocatalytic reduction of carbon dioxide into solar fuels furnishes a gratifying solution to utilize and reduce carbon dioxide emission and simultaneously generate renewable energy to sustain the societies. So far, titanium oxide-based semiconductors have been the most prevalently adopted catalysts in carbon dioxide photoreduction. This mini-review provides a general summary of the recent progresses in titanium oxide-catalyzed photocatalytic reduction of carbon dioxide. It first illustrates the use of structural engineering as a strategy to adjust and improve the catalytic performances. Then, it describes the introduction of one/two exogenous elements to modify the photocatalytic activity and/or selectivity. Lastly, it discusses multi-component hybrid titanium oxide composites.

关键词： photocatalysis carbon dioxide reduction semiconductors titanium oxide renewable fuels

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The modification of titanium in mesoporous silica for Co-based Fischer–Tropsch catalysts

《化学科学与工程前沿（英文）》 2022年第16卷第8期页码 1224-1236 doi: 10.1007/s11705-022-2139-1

摘要： Ordered SBA-15 mesoporous silica with incorporated titanium was successfully synthesized via a one-pot hydrothermal crystallization method. The characterization including powder X-ray diffraction, Brunauer–Emmett–Teller, transmission electron microscope, temperature-programmed reduction, temperature-programmed desorption, Fourier transform infrared and ultraviolet-visible-near infrared spectrometer was performed to explore the physical and chemical structures of both the supports and the catalysts. The results showed that titanium was successfully incorporated into the mesoporous silica framework with a limited amount of titanium (Si/Ti > 20), and the mesoporous structure was retained. However, the increased titanium content inevitably resulted in the formation of anatase TiO ₂ particles on the support surface. The increased incorporated titanium strengthened the interactions between cobalt species and supports, which was favorable for the cobalt species dispersion, despite the limited cobalt oxide reducibility. The enhanced metal-support interactions were beneficial for the CO/H₂ ratio at the active cobalt sites, which facilitated the formation of more C₅₊ hydrocarbons. This study provides a promising method for support modification with incorporated-heteroatoms for the rational development of Fischer–Tropsch catalysts.

关键词： Fischer–Tropsch synthesis titanium incorporation mesoporous silica metal-support interactions C₅₊ selectivity

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Machinability of damage-tolerant titanium alloy in orthogonal turn-milling

Tao SUN, Lufang QIN, Junming HOU, Yucan FU

《机械工程前沿（英文）》 2020年第15卷第3期页码 504-515 doi: 10.1007/s11465-020-0586-2

摘要： The damage-tolerant titanium alloy TC21 is used extensively in important parts of advanced aircraft because of its high strength and durability. However, cutting TC21 entails problems, such as high cutting temperature, high tool tip stress, rapid tool wear, and difficulty guaranteeing processing quality. Orthogonal turn-milling can be used to solve these problems. In this study, the machinability of TC21 in orthogonal turn-milling is investigated experimentally to optimize the cutting parameters of orthogonal turn-milling and improve the machining efficiency, tool life, and machining quality of TC21. The mechanism of the effect of turn-milling parameters on tool life is discussed, the relationship between each parameter and tool life is analyzed, and the failure process of a TiAlN-coated tool in turn-milling is explored. Experiments are conducted on the integrity of the machined surface (surface roughness, metallographic structure, and work hardening) by turn-milling, and how the parameters influence such integrity is analyzed. Then, reasonable cutting parameters for TC21 in orthogonal turn-milling are recommended. This study provides strong guidance for exploring the machinability of difficult-to-cut-materials in orthogonal turn-milling and improves the applicability of orthogonal turn-milling for such materials.

关键词： orthogonal turn-milling damage-tolerant titanium alloy tool life and failure machined surface integrity machinability

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基于二硫化钛可饱和吸收体的被动锁模掺铒光纤激光器 Research Articles

尚新新1,3,4,郭林广1,3,4,张华年2,李登旺1,3,4,岳庆炀1,3,4

《信息与电子工程前沿（英文）》 2021年第22卷第5期页码 615-766 doi: 10.1631/FITEE.2000341

摘要：本文采用液相剥离法和旋涂法合成调制深度为5.08%、饱和强度为10.62 MW/cm2的二硫化钛聚乙烯醇薄膜型可饱和吸收体。由于二硫化钛可饱和吸收体具有很强的非线性饱和吸收特性，在掺铒锁模光纤激光器中观测到两种类型的光孤子。当泵浦功率达到67.3 mW时，产生重复率为1.716 MHz、脉宽为6.57 ps的传统锁模脉冲串，其输出光谱中心为1556.98 nm、半高全宽为0.466 nm，且有明显对称的Kelly边带。通过调整偏振控制器，得到另一种锁模脉冲，在517.2 mW泵浦功率下，其最大输出功率为3.92 mW，脉冲能量为2.28 nJ。实验证明层状二维材料二硫化钛具有优异的非线性饱和吸收特性，在超快光子学领域具有广阔应用前景。

关键词：光纤激光器；被动锁模；可饱和吸收体；二硫化钛

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Pd-Ni nanoparticles supported on titanium oxide as effective catalysts for Suzuki-Miyaura coupling reactions

Dongxu Han, Zhiguo Zhang, Zongbi Bao, Huabin Xing, Qilong Ren

《化学科学与工程前沿（英文）》 2018年第12卷第1期页码 24-31 doi: 10.1007/s11705-017-1669-4

摘要： We have successfully prepared a series of Pd-Ni/TiO catalysts by a one-step impregnation-reduction method. Among these catalysts with different compositions of Ni and Pd, the one with the Ni:Pd ratio of 2.95 showed the best activity. Small monodispersed Pd-Ni bimetallic nanoparticles were loaded on the surface of titanium oxide nanopowder as confirmed with TEM and EDS mapping. The XPS analysis demonstrated that Pd exists as 31% Pd(II) species and 69% Pd(0) species and all nickel is Ni(II). The prepared Pd-Ni/TiO exhibited enhanced catalytic activity compared to an equal amount of Pd/TiO for Suzuki-Miyaura reactions together with excellent applicability and reusability.

关键词： Pd-Ni bimetallic nanoparticles nanocatalysis Suzuki-Miyaura reaction titanium oxide

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Insight into the effect of surface carboxyl and amino groups on the adsorption of titanium dioxide for

Wenlong Zhang, Xuyang Zhao, Lin Zhang, Jinwei Zhu, Shanshan Li, Ping Hu, Jiangtao Feng, Wei Yan

《化学科学与工程前沿（英文）》 2021年第15卷第5期页码 1147-1157 doi: 10.1007/s11705-020-1978-x

摘要： In this study, TiO functionalized with organic groups were prepared to study the effect of carboxyl and amino groups on the adsorption behavior of TiO for the removal of acid red G (ARG) as an anionic dye from aqueous solution. TiO was successfully modified with carboxyl and amino groups by using the hydrolysis method with oxalic acid (OAD, with two carboxyl groups), ethylenediamine (EDA, with two amino groups) and DL-alanine (DLA, with one carboxyl group and one amino group) at low temperature (65 °C) and labeled as OAD-TiO , EDA-TiO and DLA-TiO , respectively. The ARG uptake by the functionalized TiO samples was largely dependent on the functional groups. The interaction between ARG and the functional organic groups on the TiO samples plays an important role in the adsorption process, which leads to the excellent adsorption performance (higher capacity and faster adsorption rate) of the functionalized TiO samples than that of P25 (commercial TiO without modification). Furthermore, there is no obvious loss of the adsorption capacity for the functionalized TiO even after 5 adsorption-desorption cycles, which indicated the good reusability of the modified TiO samples for anionic dye removal from aqueous solution.

关键词： amino group carboxylic group titanium dioxide ARG adsorption