ADVANCED POWDER TECHNOLOGY
·
2022
·
IF 4.969
He Zhang,Jun-Ru Liu,Zhi-Bo Li,Xiao-Chun Deng,Guo-Hua Zhang,Kuo-Chih Chou
In this study, high-performance fine-grained W-Cu sintered blocks with the addition of dispersed Al 2 O 3 particles were successfully produced by low temperature liquid-phase sintering, using the raw material of ultrafine W-Cu alloy powder. The ultrafine W-Cu alloy powder was obtained by a two-step reduction process composed of stages of carbothermal reaction and hydrogen deep deoxidation. The fine Al 2 O 3 grains with uniform distribution in W-Cu alloy were introduced by spray method, leading to the decrease of W grain size and W-W connectivity. The relative densities of all sintered blocks were>97%, and a higher degree of densification ensures that the alloy has excellent comprehensive properties. With the increase of Al 2 O 3 content, W grain size and W-W connectivity of sintered W-Cu samples decrease from 664 nm to 472 nm and 0.2 to 0.14, respectively. The W-Cu alloy with the ultimate tensile strength of 415 MPa and the highest elongation of 7.22% was obtained when the addition amount of Al 2 O 3 was 0.5 wt%. At the same time, it also possessed the maximum bending strength of 1028 MPa and microhardness of 312 HV, respectively. In addition, due to the good network structure of Cu and uniform three-phase distribution, the sintered samples had excellent conductivity and compressive strength.
研究领域:
材料科学
·
冶金工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
·
2018
·
IF 3.412
Xing Chen,David Julian McClements,Jian Wang,Liqiang Zou,Sumeng Deng,Wei Liu,Chi Yan,Yuqing Zhu,Ce Cheng,Chengmei Liu
Particle-stabilized W1/O/W2 emulsion gels were fabricated using a two-step procedure: (i) a W1/O emulsion was formed containing saccharose (for osmotic stress balance) and gelatin (as a gelling agent) in the aqueous phase and polyglycerol polyricinoleate (a lipophilic surfactant) in the oil phase; (ii) this W1/O emulsion was then homogenized with another water phase (W2) containing wheat gliadin nanoparticles (hydrophilic emulsifier). The gliadin nanoparticles in the external aqueous phase aggregated at pH 5.5, which led to the formation of particle-stabilized W1/O/W2 emulsion gels with good stability to phase separation. These emulsion gels were then used to coencapsulate a hydrophilic bioactive (epigallocatechin-3-gallate, EGCG) in the internal aqueous phase (encapsulation efficiency = 65.5%) and a hydrophobic bioactive (quercetin) in the oil phase (encapsulation efficiency = 97.2%). The emulsion gels improved EGCG chemical stability and quercetin solubility under simulated gastrointestinal conditions, which led to a 2- and 4-fold increase in their effective bioaccessibility, respectively.
研究领域:
食品科学
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药学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
METALLURGICAL AND MATERIALS TRANSACTIONS A-PHYSICAL METALLURGY AND MATERIALS SCIENCE
·
2019
·Vol. 50
·期 7
·3301-3309
·
IF 1.985
Xiong Z. H.,Yang Y. F.,Kondoh K.,Misra R. D. K.
A uniform core–shell-structured W-coated Al powder was efficiently prepared by using fluidized bed chemical vapor deposition. The deposited W prevented the defluidization of Al powder and thereby enabled the controlled preparation of core–shell powder with different W-contents. Both the shell and activated sintering of the deposited nano-sized W particles contributed to the formation of a network W-skeleton in the composite. Compared with the W particles and/or aggregates formed from the powder mixture, the formation of W-skeleton which has better interface bonding with the Al matrix may create an excellent and continuous seepage pathway for electrons, resulting in superior electrical conductivity. In addition, the uniform W-skeleton structure led to enhanced tensile strength but a lower ductility. However, the negative response of continuous W-skeleton to the ductility can be ignored when the width of W-skeleton was in the 200 to 300 nm range. The W-content was optimized at 5 wt pct to obtain a good combination of mechanical properties and electrical conductivity.
研究领域:
材料科学
·
复合材料
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产品关联
DOI
高影响因子
JOURNAL OF MATERIALS CHEMISTRY
·
2012
·Vol. 22
·期 31
·15887-15893
·
IF 5.968
Hongde Luo,Jie Liu,Xiao Zheng,Lixian Han,Kuaixia Ren,Xibin Yu
Trivalent ions B3+, Al3+ and Ga3+ have been introduced into Sr3SiO5:Ce3+ in this study. Among these ions, Al3+ and Ga3+ act as charge compensators and significantly enhance the maximum emission of Ce3+ by about 100% and 90%, respectively. Then, Al3+, Eu2+ co-doped Sr3SiO5:Ce3+ phosphors have been researched, which indicate that the emission spectra can be tuned from 530 to 575 nm by changing the concentration of Eu2+. The CIE chromaticity coordinates of the phosphors were calculated from (0.342, 0.518) to (0.442, 0.479). This indicates a potential for applications in daylight LEDs or warm-white LEDs.
研究领域:
材料科学
·
光学
✓ 已验证
DOI
高影响因子
Catalysts
·
2019
·Vol. 9
·期 3
·288
·
IF 3.444
Feihu Liu,Zhong Wang,Da Wang,Dan Chen,Fushan Chen,Xuebing Li
The CeO2ordinary amorphous, nanopolyhedrons, nanorods, and nanocubes were prefabricated by the hydrothermal method, and employed as carriers of Fe/W–CeO2catalysts to selectively catalyze the reduction of NO with ammonia. Characterization results indicated that the morphology of CeO2support originated from selectively exposing different crystal surfaces, which has a significant effect on oxygen vacancies, acid sites and the dispersion of Fe2O3. The CeO2nanopolyhedrons catalyst (Fe/W–CeO2–P) showed most oxygen vacancies, the largest the quantity of acid sites, the largest BET (Brunauer-Emmett-Teller) surface area and the best dispersion of Fe2O3, which was associated with predominately exposing CeO2(111) planes. Consequently, the Fe/W–CeO2–P catalyst has the highest NO conversion rate in the temperature range of 100–325 °C among the ordinary amorphous, nanorods, and nanocubes Fe/W–CeO2catalysts.Keywords:morphology;Fe/W–CeO2;nanopolyhedra;CeO2(111) planes
研究领域:
催化化学
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材料科学
✓ 已验证
DOI
高影响因子
Nanoscale
·
2022
·Vol. 14
·期 13
·5002-5009
·
IF 8.307
Tiantian Dai,Zanhong Deng,Shimao Wang,Xiaodong Fang,Gang Meng
With features of innate tunnels and oxygen vacancies derived from a unique geometrical structure and sub-stoichiometric compositions, W18O49 nanowires have been explored as multifunctional materials with diverse applications. Though thermal oxidation offers a facile method to synthesize patterned W18O49 nanowires, the relatively high growth temperature (≳500 °C) hinders their emerging applications in flexible or wearable electronics. In this work, aiming to lower the growth temperature of W18O49 nanowires by thermal oxidation, the temperature and oxygen partial pressure dependent growth has been systematically investigated for both W films and powders. W18O49 nanowires could be steadily obtained with appropriate temperature and oxygen pressure ranges for both cases, while the growth temperature of a W film (metastable β phase dominant) could be much lower than that of W powder (α phase). The structural analysis indicates that metastable β-W is susceptible to oxidation in comparison with α-W and thus generates oxidation-induced chemical compression for nanowire growth. The growth temperature of W18O49 nanowires could be reduced to ca. 400 °C, which paves the way for the in situ patterning of W18O49 nanowires on indium-tin-oxide (ITO) glass substrates and flexible substrates.
研究领域:
材料科学
·
纳米技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ChemistrySelect
·
2025
·Vol. 10
·期 37
·e02789
·
IF 2
Li Zhong,Yuxin Duan,Meiying Wang,Xiao Xu,Minghuan Qian,Xu Jia
The polymers of N , N -diethylacrylamide (DEA) exhibit temperature-dependent sensitivity attributable to the presence of both hydrophilic and hydrophobic groups. However, their lower critical solution temperature (LCST) is only 25 °C, a limitation that restricts their practical applications. Previous studies have shown that the incorporation of cationic monomers for copolymerization can enhance the LCST of polymers. In this study, dimethyldiallylammonium chloride (DMDAAC) and DEA were selected for copolymerization to obtain a series of thermosensitive water-soluble polymers, poly(DMDAAC- co -DEA). Structure and properties were characterized using FT-IR, 1 H NMR, TG-DSC, and surface tension test. Combined with the critical phase transition mechanism, it was determined that the hydrophilicity of the polymer underwent a gradual increase in proportion with the increase of DMDAAC blocks in polymers, and the LCST exhibited an increase of up to 36.8 °C. The relationship between polymer structure and demulsification performance was also explored, as represented by the application of O/W emulsion. The experimental findings demonstrated that all poly(DMDAAC- co -DEA) products exhibited effective demulsification performance. The demulsification rate of the polymers with 30%, 50%, and 70% of DMDAAC could reach 97.03%, 98.20%, and 98.40% respectively, which shows great potential for the petroleum demulsification application. Graphical Water-soluble polymer Poly(DMDAAC- co -DEA) are synthesized using a three-step heating method. A comprehensive investigation is conducted into the relationship between its LCST and copolymerization ratio, resulting in the elucidation of the underlying mechanism. Furthermore, the demulsifying properties of the copolymer are investigated.
研究领域:
高分子化学
·
石油化学
·
胶体与界面科学
·
功能材料
·
分离技术
✓ 已验证
产品关联
DOI
高影响因子
CATALYSIS LETTERS
·
2023
·
IF 2.8
Zhu Peng,Han Chunyang,Xia Haian
Catalytic hydrogenolysis of xylose to ethylene glycol (EG) and 1,2-propanediol (1,2-PG) is an important way for the high-value valorization of biomass. Herein, Ni-W/CeO 2 catalysts prepared by incipient-wetness impregnation method were used for the hydrogenolysis of xylose to EG and 1,2-PG. Several characterizations such as X-ray diffraction (XRD), Transmission electron microscopy (TEM) and X-ray photoelectronic spectroscopy (XPS) were used to analyze the physicochemical properties of the catalysts. The effects of different Ni/W ratios and reaction conditions on the hydrogenolysis performance of the catalyst were investigated. The doping of W promoted the selective cleavage of C–C and C-O bonds of xylose, thus improved the yield of EG 1,2-PG. The doping of W can form interactions with Ni and increase the oxygen vacancy concentration of CeO 2 , which have a significant impact on the catalyst activity. When the Ni: W ratio is around 1:1, the catalyst has the best activity, and the total yield of diols can reach about 43.2%.. When xylan was used as the substrate, the total yield of diols can reach to 58.7%. The possible reaction mechanism of xylose hydrogenolysis was also discussed. This work developed a new catalyst system for the directional conversion of xylose to EG and 1,2-PG, which provided a new idea for the design of catalyst to converting lignocellulose, especially carbohydrate into high-value chemicals. Graphical Abstract Ni-W/CeO 2 with different Ni/W ratio are efficient catalysts for hydrogenolysis of xylose to EG and 1,2-PG.
研究领域:
催化化学
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生物质转化
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2022
·
IF 10.53
Li Peng,Zhengqi Wu,Boxuan Wang,Hua Liu,Chun Zhang,Xuehong Gu
Pure silica MFI (Si-MFI) zeolite membranes with desirable hydrophobicity have the potential to separate ethanol/water mixture. However, its separation performance would significantly decrease in the long-term operation due to the presence of silanol groups formed in alkaline media. In this work, silanol-free MFI zeolite membranes were prepared by the incorporation of tungsten in MFI framework. The occurrence of silanol group can be prevented by formation of W–O–Si bridges. The synthesis parameters affected the W-MFI zeolite membranes’ microstructure and separation performance. For 5 wt% ethanol solution, the W-MFI zeolite membranes prepared at optimum condition showed stable separation performance of permeation flux as 2.81 kg m −2 h −1 with separation factor as 32 over 80 h at 60 °C. The membrane was characterized by XRD , DR UV–vis, XPS and 29 Si NMR, and the results confirmed the incorporation of W and the absence of silanol groups. This research showed that W-MFI zeolite membranes are promising candidates for ethanol extraction with high stability.
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
ACS Sensors
·
2022
·
IF 9.618
Xiafen Hu,Xiang Li,Huimin Yang,Chengjia Xu,Weiqiang Xiong,Xiang Guo,Changsheng Xie,Dawen Zeng
Defect engineering has received extensive attention as an effective method to tune the gas sensing properties of semiconductor materials. Here, defective WO3 (D-WO3) nanosheets were obtained by a simple hydrogenation process with a detection limit as low as 5 ppb for dimethyl trisulfide (DMTS) and a response of 2.3 times that of the initial WO3 nanosheets to 100 ppb DMTS. Importantly, X-ray photoelectron spectroscopy and Raman spectroscopy confirmed the partial loss of oxygen atoms in D-WO3 nanosheets, and density functional theory calculations found that the W sites near the oxygen defect showed higher adsorption energy for DMTS and transferred more electrons during the gas interaction, indicating that the active W site caused by oxygen atom loss can effectively enhance the reactivity of two-dimensional WO3 nanosheets. Different from the traditional oxygen defect model, this work reveals the positive effect of active metal sites on gas sensing for the first time, which is expected to provide an effective reference for the sensing application of defect engineering in metal oxides.
研究领域:
材料科学
·
传感器技术
·
表面化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
INDUSTRIAL CROPS AND PRODUCTS
·
2025
·
IF 6.2
Mengyao Cai,Xiaofeng Wang,Na Zhu,Wanjin Hu,Shuxiao Zhang,Shuishi Tan,Chunhua Zhang,Sijie Zhou,Lixin Du,Liangjun Xia
The excessive use of antibiotics and subsequent release into the aquatic environment causes deleterious effects on organisms. Using easily separable catalysts to remove antibiotics from aquatic environments is an effective strategy to release the burden of the aquatic ecosystem. Herein, as the natural porous cellulose fiber, Juncus effusus (JE) exhibits distinctive designability on the functional materials. The JE-based W-doped Bi 2 S 3 photocatalysts (W-Bi 2 S 3 -JE) were obtained by in-situ coating on the surface of JE fibers to improve the photodegradation performance of tetracycline (TC) antibiotic pollutants. Owing to the natural porous net-working structure of JE fiber, the aggregation of particles is reduced, promoting adsorption and photocatalysis. Under the condition of pH = 3.0 and mass of photocatalyst is 100 mg, the photodegradation efficiency is 98 % under irradiation for 180 min and the photodegradation efficiency could maintain 78 % after five cycles. Finally, the cultivation of crops was conducted to investigate the purification property of the solution after photocatalytic degradation. Compared with the solution before photodegradation, mung bean seeds can take root and germinate well irrigated by the solution after photodegradation and the growth is as strong as that of agricultural irrigation water. The W-Bi 2 S 3 -JE photocatalyst provides an attractive approach to restore the aquatic ecosystem polluted by antibiotics of TC, improving the application potential in environmental remediation.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
Molecular Catalysis
·
2022
·
IF 5.089
Yaping Yang,Xuesong Liu,Zhiming Sui,Yanghui Wang,Ping Fang,Peng Jiang,Xiaodong Wu
The purpose of this study is to investigate the interaction of Ce and W species with TiO 2 , Al 2 O 3 and SiO 2 supports, so as to illustrate the influence of supports and distribution of Ce, W species on SCR reaction. It is found that low-temperature activity followed the order of CeW > CeWTi > CeWAl > CeWSi. The reasons for the various activity of the catalyst were investigated by a series of characterization. The low-temperature NH 3 -SCR activity is associated with the surface concentrations of Ce 3+ , oxygen vacancies and active oxygen species, which are dominated by the dispersion and interactions of Ce/W species with the supports. Arising from interactions of Ti 4+ with high-density electron cloud, finely dispersed Ce and W species facilitate the W-Ce synergism and produce more active oxygen. All these contribute toTiO 2 can make Ce and W species in an ideal distribution, so the corresponding catalyst shows excellent NO x conversion of CeWTi catalyst at 200–350 °C. The reaction process observed by in situ DRIFT indicated that the NH 3 -SCR reaction on CeO 2 -WO 3 containing catalysts mainly follow Langmuir-Hinshelwood (L-H) mechanism at low temperature. Based on the analysis of the characterization and reaction process, it is concluded that the control step of NH 3 -SCR reaction at low temperature over CeO 2 -WO 3 containing catalysts is the adsorption and activation of NO x .
研究领域:
催化化学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）