MICROPOROUS AND MESOPOROUS MATERIALS
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2015
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IF 3.453
Jianming Zhang,Meng Li,Yanjun Lin,Cheng Liu,Xiangyan Liu,Lu Bai,Deng Hu,Gaofeng Zeng,Yanfeng Zhang,Wei Wei,Yuhan Sun
All-silica zeolite DDR was prepared by microwave-aided hydrothermal synthesis and characterized by X-ray diffraction, scanning electron microscopy, infra-red spectroscopy, nitrogen adsorption , elemental analysis and thermal gravimetric analysis . Microwave-aided heating significantly reduced the synthesis time from 25 d to 3 d and crystal size from 8 μm to 2 μm. With the help of seeding, the synthesis time and crystal size were further reduced to 6 h and 0.7 μm respectively. The crystal size decreased with seed content. The fragmentation of seed crystals had positive impact on reducing crystal size and increasing product yield. The aging of mother liquor and decrease of H 2 O/SiO 2 had little impact on crystal size.
研究领域:
材料科学
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化学工程
✓ 已验证
DOI
高影响因子
Catalysis Science & Technology
·
2017
·Vol. 7
·期 24
·6050-6058
·
IF 5.773
Wei Zhang,Wei Hou,Tongsuo Meng,Wenxia Zhuang,Jingyan Xie,Yu Zhou,Jun Wang
Vanadium (V)-containing all-silica beta-zeolites (VSi-Beta) were directly synthesized using a dry-gel-conversion route, in which the gel was prepared from the acid-catalysed co-hydrolysis of a silica precursor and ammonium metavanadate. Besides the framework isolated V species, VSi-Beta contained tetrahedral [V2O7]4− and (VO3)nn− species that were bonded to the framework with a high dispersion. These V species resisted the over-oxidation of fructose and efficiently catalyzed the oxidation of 5-hydroxymethylfurfural (HMF) into 2,5-diformylfuran (DFF). As a result, VSi-Beta demonstrated high activity in the one-pot and one-step conversion of fructose into DFF using atmospheric oxygen (O2) in the presence of sulfuric acid, affording a high yield of 86.3% and a maximum turnover number (TON) of 270. The catalyst can be easily recovered by filtration and exhibits good reusability. Various other carbohydrates (glucose, sucrose, inulin, raffinose, maltose and starch) were also effectively converted into DFF using VSi-Beta.
研究领域:
化学工程
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催化科学
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产品关联
DOI
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
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2022
·
IF 9.221
Haiyan Zhang,Fei Feng,Yangyang Zhao,Bin Zhao,Lei Li,Dan Zheng,Xinxin Li
Increasing the aspect ratio of the microchannels of microfabricated gas chromatographic columns (μGCCs) can allow analytes to quickly reach equilibrium between the stationary phase and mobile phase , which helps improve their separation performance. In this paper, an all-silicon microfabricated gas chromatographic column (AS-μGCC) with a high aspect ratio was proposed and fabricated using deep reactive-ion etching (DRIE) and silicon direct bonding. Two AS-μGCCs with the lengths of 2 m and the aspect ratios of 6.6 (100 µm-width × 660 µm-depth) and 25 (30 µm-width × 750 µm-depth) were successfully fabricated. The effects of different aspect ratios on the column efficiency of AS-μGCCs were studied. A separation experiment showed that the column efficiency of the AS-μGCC with an aspect ratio of 25 (AS-μGCC-25) was 12 times higher than that of the AS-μGCC with an aspect ratio of 6.6 (AS-μGCC-6.6). The column efficiency of the AS-μGCC-25 was 1961 plates/m, and a heavy hydrocarbon mixture (C8–C20) could be separated using AS-μGCC-25 within 4.5 min
研究领域:
分析化学
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微制造技术
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产品关联
DOI
高影响因子
DALTON TRANSACTIONS
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2025
·
IF 3.3
Yijia Shi,Shiqi Wen,Xiaotao Yu,Yuxuan Chen,Yinying Jin,Min Guo,Song Lu,Jiadi Ying,Tiancun Liu,QI Shen,Yeqing Wang,Zhixin Yu
Rapid and straightforward synthesis of all-silica zeolites is essential for scaling up their industrial applications in adsorption and separation. However, the synthesis typically necessitates the use of complex organic structure-directing agents (OSDAs) and/or fluoride, presenting challenges in the development of straightforward strategies. Herein, a siliceous TON zeolite, referred to as Si-TON, is successfully obtained without the need for any costly OSDAs, utilizing seeds and methanol as facilitating agents. Various analyses validate that methanol acts as both a dynamic stabilizer and a solvent, which can be totally removed without high temperature calcination. This approach circumvents the requirement for high-temperature calcination to achieve open channels in the TON zeolite, distinguishing it from traditional synthesis method. Additionally, metal species (Co, Fe, and Zr) can be incorporated into the TON zeolite to form heteroatom-substituted TON samples, thereby offering a viable strategy for the preparation of heteroatom doping catalysts that exhibits excellent performance in various catalytic reactions. Furthermore, the as-synthesized Si-TON zeolite exhibits high methanol adsorption capacity, stands as a candidate adsorbent for methanol removal.
研究领域:
材料科学
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化学合成
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催化
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物理化学
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工业化学
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产品关联
DOI
PubMed
高影响因子
Nature Communications
·
2024
·Vol. 15
·期 1
·1-11
·
IF 14.7
Wang Kun,Shi Jianwei,Lai Wenxuan,He Qiang,Xu Jun,Ni Zhenyi,Liu Xinfeng,Pi Xiaodong,Yang Deren
Integrated circuit anti-counterfeiting based on optical physical unclonable functions (PUFs) plays a crucial role in guaranteeing secure identification and authentication for Internet of Things (IoT) devices. While considerable efforts have been devoted to exploring optical PUFs, two critical challenges remain: incompatibility with the complementary metal-oxide-semiconductor (CMOS) technology and limited information entropy. Here, we demonstrate all-silicon multidimensionally-encoded optical PUFs fabricated by integrating silicon (Si) metasurface and erbium-doped Si quantum dots (Er-Si QDs) with a CMOS-compatible procedure. Five in-situ optical responses have been manifested within a single pixel, rendering an ultrahigh information entropy of 2.32 bits/pixel. The position-dependent optical responses originate from the position-dependent radiation field and Purcell effect. Our evaluation highlights their potential in IoT security through advanced metrics like bit uniformity, similarity, intra- and inter-Hamming distance, false-acceptance and rejection rates, and encoding capacity. We finally demonstrate the implementation of efficient lightweight mutual authentication protocols for IoT applications by using the all-Si multidimensionally-encoded optical PUFs.
研究领域:
电气工程
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材料科学
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光学
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密码学
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物联网
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产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）