POWDER METALLURGY AND METAL CERAMICS
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2021
·Vol. 59
·期 11
·651-660
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IF 0.511
Zhangjun Bai,Yuhong Chen,Lu Li,Jiaxin Li,Yuewei Cheng
In this study, Ta–W–Ti–Al multialloys were prepared by spark plasma sintering (SPS) as a new powder metallurgy technology based on discharge activation and thermoplastic deformation process. The oxidation behavior of the as-obtained sintered alloys were investigated under 1000 and 1200°C in air atmosphere. Microstructures and phase compositions of alloys and oxides were analyzed using various analytical methods, such as X-ray diffraction (XRD), scanning electron microscopy (SEM) equipped with energy dispersive spectroscopy (EDS), and backscatter electron microscopy (BSE). The sintered samples possessed relative densities reaching up to 98% with achievable densification. The densities of all specimens with high Ti contents exceeded 100%, suggesting the great impact of Ti addition on liquid-phase precipitation. Intermetallic compounds were formed in Ta–W–Al alloys, and samples with high Ti contents displayed grain boundary phases rich in titanium and oxygen. The addition of Ti and Al effectively improved the oxidation resistance of the resulting alloys. A protective alumina layer was formed after oxidation at 1000°C that made oxidation kinetics of the alloys obeying pseudo-parabolic laws. At the oxidation temperature of 1200°C, Al 2 O 3 reacted with Ta 2 O 5 to form the AlTaO 4 alloy with reduced protective effect. The mass gain in the alloys after oxidation at 1200°C for 4 h was about 7 times higher compared to processing at 1000°C.
研究领域:
材料科学
·
冶金工程
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DOI
高影响因子
MICROPOROUS AND MESOPOROUS MATERIALS
·
2021
·
IF 5.455
Kang Tang,Weilong Hou,Xiaoshu Wang,Wen Xu,Xinqing Lu,Rui Ma,Yanghe Fu,Weidong Zhu
The titanosilicate zeolite catalyzed epoxidation of propylene with hydrogen peroxide (H 2 O 2 , HP) to propylene oxide (PO), the so-called HPPO, is more eco-efficient, compared to the chlorohydrin process and the epoxidation using organic hydroperoxides. However, the zeolite catalysts used in the HPPO process are easily deactivated, because the main byproduct propylene glycol (PG) and other heavy byproducts with high boiling points, derived from the solvolysis of PO, are deposited inside the zeolite micropores. In the present work, trimethylsilylated Ti-MWW zeolites, named Si–Ti-MWW, were developed for the HPPO process. In combination with the results from extensive characterizations for the prepared zeolites, it is found that the trimethylsilylation merely occurs on the external surface of Ti-MWW crystals and can significantly enhance the hydrophobicity , but not alter the coordination states of the Ti species and textural properties of the zeolites. The catalytic properties of Ti-MWW and Si–Ti-MWW were compared in propylene epoxidation. The results show that the solvolysis of PO to the byproducts can be effectively inhibited over the hydrophobic zeolite surface, making Si–Ti-MWW exhibit a much higher selectivity for PO and a much better stability and reusability than the parent Ti-MWW in the HPPO process. The current study, therefore, provides a new approach to develop efficient catalysts for the HPPO process.
研究领域:
化学工程
·
催化科学
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DOI
高影响因子
CONSTRUCTION AND BUILDING MATERIALS
·
2024
·
IF 7.4
Lin Wang,Hongqiang Chu,Jiaxuan Xie,Mingzhi Guo,Linhua Jiang,Xiang Xi,Yi Fang,Wei Zhao
Concrete corrosion in wastewater pipelines is caused by biogenic sulfuric acid produced locally by sulfur-oxidizing microorganisms. Concrete mixtures are commonly modified to prevent this form of corrosion by adding biocides to inhibit their biological activities. However, using biocides is not always desirable because of their limited lifespan and potential for leaching into the environment. Therefore, there is a need to develop more durable alternatives to prevent microbial-induced corrosion of concrete. In this study, three types of Cu-Ti amorphous alloys (Cu 35 Ti 65 , Cu 50 Ti 50, and Cu 65 Ti 35 ) were prepared by ball milling, and compared with commercially available TiO 2 nanoparticles to assess their effects on the resistance of the microbial-induced corrosion performance of mortar. Detailed investigations were conducted on the appearance, mechanical properties, and corrosion depth of mortars at various exposure durations in an accelerated biocorrosion environment. The results revealed that the mortars mixed with Cu 35 Ti 65 , Cu 50 Ti 50 , Cu 65 Ti 35 , and TiO 2 nanoparticles exhibited significantly better resistance to microbial-induced corrosion than the reference mortars. The resistance to microbial-induced corrosion of the mortar mixed with Cu 50 Ti 50 was the best. The superior antimicrobial corrosion performance of the mortar containing Cu-Ti amorphous alloy is influenced by both smaller particle sizes and higher sterilization performance. These findings can contribute to the development of novel applications of amorphous alloys in functional concrete.
研究领域:
土木工程
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材料科学
·
微生物学
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产品关联
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2021
·
IF 6.707
Longwen Li,Lin Chi,Hongxu Zhang,Shuming Wu,Han Wang,Zhimin Luo,Yanwei Li,Yanhui Li
This article prepared a nanoparticle (NP) Ti-PDA made from bis (2-hydroxy propionic acid) diammonium titanium hydroxide (Ti-BALDH) chelating dopamine (DA), as a photocatalyst to absorb and reduce hexavalent chromium (Cr(VI)) under visible light with recycling ability from waste water. Ti-PDA NPs with part of TiO 2 -like structure can perform some function of TiO 2 , while participation of PDA will not only broaden absorption spectrum from UV to visible light, but offer the ability to absorb Cr(VI). Compared with TiO 2 Ti-PDA NPs would make full use of sunlight, increasing the photocatalytic efficiency. The adsorption results of Ti-PDA NPs for Cr(VI) showed that the adsorption capacity of Ti-PDA NPs can reach 500.24 mg/g when the concentration of Cr(VI) was 300 mg/L, and the adsorption data matched well with the Langmuir isotherm model, and confirmed to a quasi-second-order dynamics. Under visible light irradiation, Ti-PDA NPs could reduce Cr(VI) to Cr(III) within 30 min, and can almost completely reduce Cr(VI) within 15 min even at pH = 4. After three cycles, photocatalytic reduction efficiency was still 95.02%. Thereby the toxic Cr(VI) can be effectively eliminated by Ti-PDA NPs from sewage. As a result, Ti-PDA will be a promising green photocatalyst to remove Cr(VI) in disposal of water pollution.
研究领域:
环境科学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
·
2018
·
IF 5.667
Xiaomeng Dou,Weiming Hao,Xiangqing Li,Lixia Qin,Shi-Zhao Kang
In the present work, Ti mesh loaded with Ag “nanobosk” was prepared through electro-deposition and characterized with X-ray diffraction, scanning electron microscopy and X-ray photoelectron spectroscopy. Then, the surface enhanced Raman scattering of norfloxacin on the Ti mesh loaded with Ag “nanobosk” was directly explored in norfloxacin aqueous solution. In addition, for practical purposes, the surface enhanced Raman scattering of norfloxacin was studied as a function of content of Ag, pH of solution, ions in water, and salinity, respectively. At last, the surface enhanced mechanisms were discussed preliminarily. The results indicate that the Ti mesh loaded with Ag “nanobosk” is an ultrasensitive surface enhanced Raman scattering substrate for trace norfloxacin in water. When the concentration of norfloxacin is 1 × 10 −5 mol L −1 , the enhancement factor is approximately 5.1 × 10 3 at 1389 cm −1 . And the detection limit is up to 1 × 10 -10 mol L −1 for norfloxacin under optimal conditions. Our work provides a new strategy for designing a sensing platform which is sensitive to trace norfloxacin in water and can be applied in the routine detection.
研究领域:
材料科学
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环境科学
·
分析化学
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产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2023
·
IF 15.1
Yun-fei Zhang,Jia-le Gao,Shen-gui Chen,Lei Li,Jian-hui Xu,Dan Li,Yu-feng Liu,Xin Quan,Xin Fu,Ya-zi Xie,Jing-nan Wu,Dan-ying Lin,Ting-ting Zheng
In this study, a novel 3D printed (3DP) Nb 2 O 5 /Ti electrode with a three-dimensional pore structure was prepared using selective laser melting (SLM) 3DP technology. The electrode exhibited high degradation efficiency, low energy consumption (16.02 Wh/L for 90% removal of 5 mg/L of Florfenicol (FLO)), and promising lifetime. Specifically, the 3DP 3% Nb 2 O 5 /Ti electrode maintained a 97.0% degradation efficiency for FLO within 120 min when consecutively used for 20 cycles. It was proposed that the Nb 2 O 5 served as an n-type dopant for Ti (IV), creating an electronegative surface environment that leads to stronger binding of electrons from H 2 O or FLO to the electrode surface. Consequently, the 3D-printed Nb 2 O 5 /Ti electrode exhibits higher OER potential and a greater yield of reactive oxygen species (ROSs) compared to the undoped Ti electrode. The electrode also achieved an 82.5% defluorination ratio for FLO, which is the best dehalogenation yield reported so far. Additionally, the toxicity of intermediates was significantly reduced after electrooxidation treatment, and 11 degradation products were identified by UPLC-MS/MS for potential degradation pathways identification. This study suggests that the 3D printed Nb 2 O 5 /Ti electrode holds great promise in remediating pharmaceuticals and personal care products (PPCPs)-contaminated water, and that SLM 3D printing technology is a beneficial method for producing Ti-stabilized anodes.
研究领域:
环境科学
·
电化学工程
·
毒理学
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产品关联
DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2019
·Vol. 43
·期 43
·16981-16989
·
IF 3.069
Bingying Jia,Miaojiang Wu,Hua Zhang,Yi Zeng,Gongying Wang
Titanates are frequently used as precursors to prepare transesterification catalysts with TiIV species. Unfortunately, it is challenging to control the dispersity of TiIV active sites on supports. Herein, a series of TiIV species is anchored on abundant linker vacancy sites by introducing point and large scale defects in UiO-66(Zr/Ti) with hierarchical-pore structure. The catalyst functionalized by titanium(IV) oxide bis(2,4-pentanedionate) shows excellent catalytic performance in the transesterification of dimethyl carbonate with phenyl acetate. The catalysts are characterized by XRD, FT-IR, N2 adsorption–desorption, XPS, SEM and STEM-HAADF techniques. The results demonstrate that the delicate mesopores in the support can not only exhibit a large surface area for the distribution of the active sites, but also provide better mass transfer performance. Meanwhile, the introduction of octahedral TiIV ions raises the activity of the catalyst via more coordinatively unsaturated ZrIV sites. Furthermore, using titanium(IV) oxide bis(2,4-pentanedionate) as a Ti source can effectively prevent the condensation of tetrahedral TiIV species anchored on the hierarchical-pore UiO-66(Zr/Ti) support.
研究领域:
催化
·
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2025
·
IF 2.5
Dan Wang,Wenjing Cai,Qiuxiang Feng,Feng Cao,Qianli Zhang,Qiang Xu,Li Li,Jie Liu
To develop porous solid-state materials for effective capture of radioactive iodine in both vapor and solution phases is of great importance. In this work, a Zr/Ti-based bimetallic metal-organic framework (AO-UiO-66-ZrTi11) was synthesized via a simple solvothermal method using 2, 5-bis (allyloxy)terephthalic acid, ZrCl4 and Cp2TiCl2. This MOF solid was fully characterized and extensively evaluated for its I2 capturing performance. AO-UiO-66-ZrTi11 demonstrated significantly enhanced I2 uptake capacity, achieving as high as 2.46 g·g-1 for iodine vapor and 1084.4 mg·g-1 for iodine/cyclohexane solution. Kinetic studies of iodine adsorption from solution revealed rapid kinetics, with the process fitting well to the pseudo-second order kinetic model. The superior adsorption performance of AO-UiO-66-ZrTi11 for iodine can be attributed to its unique bimetallic structural features and functional groups. This work provides valuable insights for the further development of efficient adsorbents towards capturing radioactive iodine.
研究领域:
材料科学
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核化学与放射化学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF REFRACTORY METALS & HARD MATERIALS
·
2020
·
IF 3.407
Zhaoran Chen,Dejiang Ma,Shanmin Wang,Wenhao Dai,Pinwen Zhu,Yiqing Zhu,Baochang Liu
Ti-coated diamond with different particle sizes and proper amounts of cubic boron nitride (cBN) was used to fabricate polycrystalline diamond composite (PDC) with improved wear resistance and thermal stability under high temperature and high pressure (5.5–6.5GPa, 1500–1650 °C). The ratio of Ti-coated diamond powder, cBN powder and normal diamond powder was W 30 – 50 : W 4 – 8 : W 0 – 1 = 70: 15: 15. Cobalt (Co) was used as a binder, and cemented tungsten carbide was used as a substrate to sinter a new high-performance PDC. Ti and TiC on the surface of Ti-coated diamond reacted with cBN under high temperature and high pressure to generate new ceramic phases such as TiB 2 , TiN and TiN 0.3 , which have high hardness and good wear resistance. Compared with the conventional PDC, the impact toughness and wear resistance of PDC with Ti-coated diamond and cBN addition were enhanced by 19% and 28%, respectively. The ceramic phase acts as a protective barrier, which enhances the initial graphitization and oxidizing temperature to 942–950 °C, which were 162–170 °C higher than the conventional PDC. The new ceramic barrier wrapped around the surface of the diamond and Co after the formation of the D-D (diamond-diamond) bonding will give priority to the oxidation reaction of Co and diamond with oxygen, which prohibits cobalt-catalytic graphitization of diamond, meeting the needs of PDC thermal stability and wear resistance in the field of drilling.
研究领域:
材料科学
·
地质工程
✓ 已验证
产品关联
DOI
高影响因子
Chemical Science
·
2016
·Vol. 7
·期 8
·4966-4972
·
IF 9.144
Dan Zhou,Tianjun Zhang,Qinghua Xia,Yarong Zhao,Kexin Lv,Xinhuan Lu,Renfeng Nie
A hydrothermal rota-crystallization method is developed for the one-step synthesis of a hollownest-structured zeolite precursor with the shell composed of autogenously-intergrown MWW nanosheet crystals containing a large number of stacking-pores without using any porogen or hard scaffold. This material possesses a large external surface area. By simple acid washing, the resultant Ti-containing catalyst can be directly used in the epoxidation of alkenes with hydrogen peroxide. The excellent catalytic activity over the Ti-HSZ catalyst is assumed to be due to the exposure of more Ti active sites over the MWW nanosheet crystals in the shell of the catalyst. More importantly, this Ti-HSZ catalyst washed with H2O2/ethanol solution has been reused 6 times without an appreciable decrease in both the conversion of the allyl chloride and the selectivity of the epichlorohydrin, which is ascribed to the structural stability of the hollownest-structured zeolite.
研究领域:
材料科学
·
催化化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Environmental Science-Nano
·
2019
·Vol. 6
·期 11
·3431-3441
·
IF 7.704
Bowen Xiao,Yinqing Zhang,Xiaolei Wang,Meng Chen,Binbin Sun,Tong Zhang,Lingyan Zhu
The wide production and utilization of nanoparticulate Ag and Ti inevitably result in their release into the environment. Thus far, limited information is available regarding to what extent the nanoparticulate Ag and Ti could accumulate in biota and magnify along the food chain in real natural aquatic environments. With the application of single particle inductively coupled plasma mass spectroscopy, we quantitatively demonstrated that both nanoparticulate Ag (18.8–41.0 nm) and Ti (46.6–116 nm) occurred in the water, sediment and aquatic organisms in Taihu Lake, China. Nanoparticulate Ag exhibited greater bioaccumulation potential compared to its other chemical counterparts, and also a greater bioaccumulation factor than nanoparticulate Ti. Sediment served as a main reservoir for nanoparticulate Ag and Ti, and acted as one important exposure source for invertebrates. According to the concentrations of nanoparticulate Ag and Ti in aquatic organisms at different trophic levels, including a variety of invertebrates and fish species, the total and nanoparticulate Ti appeared to be biodiluted in the food web with trophic magnification factors (TMFs) < 1. Conversely, biomagnification of nanoparticulate Ag was found in the fish food web with a TMF of 1.21, while the total Ag was biodiluted. These findings serve as the first line of evidence on the transfer behaviors of nanoparticulate Ag and Ti along the natural aquatic food chain and underline the distinctive bioaccumulation and biomagnification behaviors of nanoparticles as opposed to their other chemical counterparts.
研究领域:
环境科学
·
生态学
✓ 已验证
产品关联
DOI
高影响因子
CELLULOSE
·
2019
·Vol. 26
·期 17
·9335-9348
·
IF 3.917
Yang Yingying,Huang Wei,Guo Zengpei,Zhang Shiyu,Wu Feng,Huang Jingjing,Yang Hongjun,Zhou Yingshan,Xu Weilin,Gu Shaojin
Abstract Superhydrophobic cotton fabrics with improved ultraviolet resistance were prepared via in situ growing NH 2 -MIL-125(Ti)(Ti-MOF) nanoparticles on cotton fibers and subsequently coating with polydimethylsiloxane (PDMS) under room temperature. The synergetic effect of Ti-MOFs nanoparticles and PDMS was critical and essential for obtaining a superhydrophobic coating with anti-UV property. The surface microstructure, chemical composition, and superhydrophobic property of the as-prepared fabrics were characterized by K/S value, scanning electron microscopy, X-ray photoelectron spectroscopy, energy dispersive spectroscopy, and water contact angle (WCA) measurements. The as-prepared cotton fabrics not merely exhibited desirable superhydrophobic property with a water contact angle (WCA) of 154.7 ± 0.7° and a sliding angle of 3.6°, but also displayed the considerable UV resistance. The oil–water separation, stability of UV protection and superhydrophobicity were also investigated. The superhydrophobicity, anti-ultraviolet property, and K/S value of as-prepared PDMS/Ti-MOFs@cotton fabrics were stable after 300 cycles of abrasion and 5 cycles of washing. The facile synthesis technique provided a simple method for scalable construction of multifunctional fabrics. Graphic abstract
研究领域:
材料科学
·
纺织工程
·
环境科学
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）