POLYMERS FOR ADVANCED TECHNOLOGIES
·
2018
·Vol. 29
·期 12
·2982-2991
·
IF 2.137
Zhiyong Zhang,Miaojun Xu,Bin Li
The polymethacrylimide/silicate (PMI/silicate) composites were successfully prepared from the monomers of acrylonitrile (AN) and methacrylic acid (MAA) via the monomer in situ intercalation polymerization and free foaming. The formation of imide groups was monitored by Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS). The results of FTIR and XPS indicated that the imide groups were gradually formed and cyano groups were dwindling but still existed during foaming and thermal treatment. The thermogravimetric analysis results revealed that the thermal stability of the PMI/silicate composites was improved, the rate of thermal degradation was reduced, and the residue was increased because of the addition of silicates. The results of dynamic mechanical analysis revealed that the rigidity and the glass transition temperature of the composites were improved. The limit oxygen index (LOI) and cone calorimeter (CONE) test showed that the fire-retardant properties were improved because of the barrier effect of silicates. The cell morphologies of the PMI/silicate composites were characterized by scanning electron microscopy (SEM), and the results showed that the silicate particles were distributed on the cell walls, but the cells slightly cracked. The mechanical properties were measured by tensile, flexural, and compressive strength. The mechanical strength, especially flexural strength, was significantly improved. The flexural strength of PMI/MMT, PMI/kaolin, and PMI/talc containing 8 wt% silicates was improved to 172%, 240%, and 233%.
研究领域:
高分子材料
·
复合材料科学
·
材料化学
·
防火材料
·
多孔材料
✓ 已验证
DOI
高影响因子
POWDER TECHNOLOGY
·
2019
·
IF 3.413
Zhilin Xi,Shuhui Zhou,Longzhe Jin
In this work, a self-hardening foam-sol (SHF) is proposed to control the diffusion of static coal dust. The SHF was mainly synthesized by a foaming solution (composed of 1 g/L polyethylene oxide (PEO), 25 g/L sodium dodecyl sulfate (SDS), 100 g/L sodium silicate and 874 g/L water) and organic acid with a concentration range of 10 to 13 g/L. Based on fluorescence spectrophotometry , drop shape analysis, X-ray photoelectron spectroscopy and scanning electron microscopy, several conclusions could be found. The critical micelle concentration of SDS was 25 g/L, when most of the pyrene pendants were solubilized into the SDS micelles to form the hydrophobic mixed micelles, and excimer formation began to reach a maximum. The SHF had optimal wetting ability with the smallest contact angle of 17 o , due to PEO-bonded water and SDS forming hydrogen and a dual adsorption layer, which could enhance the wetting ability of the SHF on coal dust surfaces. The SHF had the best accepted loss of liquidity time (180–86 s) and self-hardening time (236–121 s) via the reaction of sodium silicate and organic acid. The pores and cracks among dust particles could be linked closely by SHF via the solid bridge force. The primary components were silica and sodium carbonate with crystal water and hydrophilic C O and C O or O–C–O functional groups. Based on the dust suppression experiment, the dust suppression efficiency was almost 100% at airflow speeds below 12 m/s. Obviously, the dust particles could be controlled via their surfaces being covered by a layer of SHF, since the SHF has strong hydrophilic properties and the solid bridge force. In addition, vehicle-mounted SHF preparation equipment was designed.
研究领域:
环境工程
·
矿业安全
·
胶体与界面化学
·
职业健康
·
颗粒物控制
✓ 已验证
DOI
高影响因子
MATERIALS RESEARCH BULLETIN
·
2024
·
IF 5.3
C. Wang,X.Z. Zheng,L. Yue,P.J. Xia,M. Xu,W.B. Dai
The exploration of stable/efficient phosphor for n -UV chip pumped white light-emitting diodes ( w LEDs) remains an arduous task. Herein, a novel series of color tunable Eu 2+ /Tb 3+ /Sm 3+ tridoped Sc-based cyclosilicate phosphors (KBaScSi 3 O 9 : Eu 2+ /Tb 3+ /Sm 3+ ) have successfully designed and obtained via facile solid-state reaction based on comprehensive consideration of rigidly structural network of host, weak electron-phonon coupling strength and spectral adjustability of codopants via energy transfer (ET). The crystallographic occupancies of Eu, Tb and Sm primary in Ba/K, Ba and Ba sites in the monoclinic host, respectively were determined on the basis of the Rietveld refinements and crystal chemistry rules. The photoluminescence (PL) properties were systematically investigated in conjunction with structural analyses, implying that the ‘warm’ white light with excellent thermal stability is stemmed from combination of optimized blue (Eu 2+ ), green (Tb 3+ ) and red (Sm 3+ ) emissions via Eu → Tb → Sm ET strategy. Interestingly, Tb ions play both roles of green light luminescent center and ET bridge to achieve cascade ET for connecting Eu/Sm ion pairs because of the adverse metal-metal charge transfer (MMCT) effect (Eu 2+ + Sm 3+ → Eu 3+ + Sm 2+ ). Furthermore, the phosphor-converted w LEDs (pc- w LEDs), by encapsulating the optimal KBS: 4 %Eu/4 %Tb/6 %Sm with commercial n -UV LED chip, show high thermal stability with satisfactory electroluminescence (EL) performances. These results indicate the KBS: Eu/Tb/Sm phosphors are potential candidates for application in high power n -UV pumped pc- w LEDs.
研究领域:
材料科学
·
发光材料
·
固态照明
·
无机化学
·
光电子学
✓ 已验证
DOI
高影响因子
OPTICS AND LASER TECHNOLOGY
·
2016
·
IF 1.879
Rong Chen,Ying Tian,Bingpeng Li,Feifei Huang,Caizhi Wang,Xufeng Jing,Junjie Zhang,Shiqing Xu
Nd 3+ /Ho 3+ co-doped silicate-germanate glass has been synthesized by high temperature melt-quenching method. Near infrared emission centered at 2 µm has been successfully obtained by incorporating Nd 3+ and Ho 3+ in present glass. The Judd-Ofelt intensity parameters Ω t (t=2, 4, 6), and radiative properties of Ho 3+ were calculated and discussed by using the Judd-Ofelt theory. The energy transfer processes and luminescence properties of Nd 3+ /Ho 3+ co-doped glasses were analyzed pumped by a conventional 808 nm laser diode . Desirable spectroscopic characteristics indicates that Nd 3+ /Ho 3+ co-doped silicate-germanate glass might be a good alternative matrix for 2 µm band mid-infrared laser.
研究领域:
光学材料
·
无机非金属材料
·
光子学
·
激光技术
·
固体物理
✓ 已验证
DOI
高影响因子
RUSSIAN JOURNAL OF GENERAL CHEMISTRY
·
2021
·Vol. 91
·期 4
·726-731
·
IF 0.868
Xu Y.,Hu Y.,Bao Q.,Zhang J.,Liu B.,Zhang Z.,Zhang Q.,Zhang H.
Copper phyllosilicate has been synthesized from a solution of sodium silicate and copper nitrate by co-precipitation under acidic conditions followed by reduction under H 2 flow for using it as the Cu/SiO 2 catalyst. The catalyst has been characterized by XRD, XPS, FTIR and Raman spectra, EDS, BET, and TEM. It is confirmed that only copper phyllosilicate and SiO 2 exist in the catalyst precursor, and there has been no CuO. Physical and chemical properties of Cu/SiO 2 catalyst have been evaluated. The Cu/SiO 2 catalyst has not only a large specific surface area and abundant mesopores but also the advantages of high dispersion of copper nanoparticles and the combination of Cu 0 and Cu + . The catalyst demonstrates high activity and selectivity in the reaction of 2-butanol dehydrogenation to methyl ethyl ketone.
研究领域:
催化化学
·
材料科学
·
物理化学
·
纳米材料
·
有机合成
✓ 已验证
DOI
高影响因子
ChemCatChem
·
2026
·Vol. 18
·期 4
·e01867
·
IF 4.1
Shiao Gao,Xiliu Wang,Lei Hu,Zhennan Yang,Xiao Zhang,Yingshuo Guo,Yu Deng,Xinyu Li,Zhijie Wu
Here, MCM-22 zeolites were synthesized by a hydrothermal synthesis method using a mother liquor recycling procedure, in which the use of organic templates was greatly reduced with a molar ratio of template to SiO 2 at 0.15 in the zeolite gel precursors. The as-prepared MCM-22 zeolites show high crystallinity and flake-like morphology with a thickness below 100 nm, possessing a high specific surface area of approximately 470 m 2 /g and substantial mesoporous volume of 0.49 cm 3 /g. The oxalic acid treatment was applied to adjust the textural properties of MCM-22 zeolite as well as the acid sites concentration from 0.43 to 0.22 mmol/g. The selective extraction of extra-framework aluminum via oxalic acid treatment leads to an increase in the ratio of Brønsted acid site amount to Lewis acid site amount (B/L ratio) from 0.59 to 1. The as-modified MCM-22 zeolite shows an enhanced propylene selectivity (44.7%) relative to the MCM-22 zeolite (35.6%). The eco-friendly synthesis strategy combined with an effective acid modification method is anticipated to expand the application of MCM-22 zeolite for designing high-performance catalysts for methanol to olefins (MTO) reaction. Graphical This work offers an eco-friendly route for the synthesis of MCM-22 zeolite via a mother liquor recycling strategy. Oxalic acid treatment enables precise control of acid sites by removing extra-framework Al, thereby suppressing the aromatic-based cycle in the MTO reaction and yielding high selectivity toward target olefins (e.g., propylene).
✓ 已验证
产品关联
DOI
高影响因子
NEW PHYTOLOGIST
·
2026
·
IF 8.7
Zhihao Pang,Sue E. Hartley,Nan Sun,Yuxiao Wang,Tangxin Chen,Wanyue Zhang,Richard R. Bélanger,Alin Song,Alexander Lux,Yongchao Liang
Summary Silicon (Si) forms a defensive barrier in roots of Si-accumulators such as rice, blocking the absorption of toxic metals and salt, but many dicotyledons do not accumulate Si, limiting the Si application in agriculture. This may be related to differences in their cell walls: mixed-linkage glucan (MLG) exists in cell walls of monocotyledons but is absent in dicotyledons. In vivo and in vitro experiments, material characterization, and genetic modification approaches were employed to investigate the structural roles of MLG in root Si barriers and its effects on plant stress resistance. Both the roots of Si transporter Lsi2 (low silicon rice 2) defective rice mutants and dead rice continued to accumulate Si, showing root Si deposition is controlled by cell wall components, but not transporters. MLG-induced Si polymerization in vitro and CslF6 (encoding an MLG synthase) controlled root MLG and Si concentrations. Overexpression of rice CslF6 in Arabidopsis, an Si non-accumulator, enabled them to form Si barriers, enhancing resistance to cadmium, chromium, and salt stress. These findings suggest that MLG serves as a structural basis for root Si barriers and that genetic modification combined with Si supply is a promising strategy to endow Si non-accumulators with Si-mediated stress resistance.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHINESE JOURNAL OF CHEMISTRY
·
2025
·
IF 5.5
Shaohua Liu,Xiaoqin Ma,Xifa Long,Yun Yang
Comprehensive Summary Birefringent crystals exhibit significant advantages in the field of polarization state modulation due to their unique optical anisotropy properties. The property optimization between bandgap and birefringence depends on the crystal structure, which is always a key scientific problem in the field of functional crystal materials design. In this work, the fluorination-oriented strategy was applied to the design of crystals with large birefringence and deep ultraviolet (DUV) cutoff edges. By introducing the fluorinated [SiF 6 ] octahedron, the arrangement orientation of the π-conjugated [C(NH 2 ) 3 ] groups was accurately regulated, thereby achieving the design and preparation of a new crystal [C(NH 2 ) 3 ] 2 SiF 6 with a large bandgap (6.34 eV) and large birefringence (0.16 @546 nm). In addition, [C(NH 2 ) 3 ] 2 SiF 6 (GSF) can obtain large-sized crystals through a simple water solution evaporation method, and it has unique advantages such as low cost and easy growth. The synergistic mechanism between the core factors of significant birefringence and wide bandgap in [C(NH 2 ) 3 ] 2 SiF 6 was revealed through experimental characterization and theoretical calculation. This work provides promising candidates with exceptional properties for DUV applications.
✓ 已验证
产品关联
DOI
高影响因子
RENEWABLE ENERGY
·
2022
·
IF 8.634
Riyang Shu,Hao Jiang,Long Xie,Xiaozhou Liu,Tao Yin,Zhipeng Tian,Chao Wang,Ying Chen
Hydrodeoxygenation (HDO) is an effective technology for the conversion of bio-oil to high quality liquid fuels, in which an active and stable catalyst is crucial to gain a high reaction efficiency. In this work, a novel bifunctional catalyst of different Ru-based biochar catalyst coupled with silicotungstic acid (HSiW) was proposed to conduct the HDO of lignin-derived phenolic compounds under mild reaction condition. Ru/C-bamboo catalyst exhibited a better HDO performance than other Ru-based biochar catalysts and commercial Ru/C catalyst. Catalyst characterizations showed that Ru/C-bamboo catalyst possessed a rich mesoporous structure of 0.06 cm 3 /g mesopore volume and 0.07 cm 3 /g micropore volume, with a large specific surface area of 209 m 2 / g. A high metal dispersion and a good hydrogen adsorption ability were achieved in Ru/C-bamboo catalyst. And Guaiacol can be completely converted to cyclohexane with 87.7% selectivity at the temperature of 140 °C. Other typical phenolic compounds were also transformed into corresponding cycloalkanes with high yields above 90% in most cases. Besides, the lignin-oil also had a great improvement on the stability and the heat value after upgradation, with an increase of hydrocarbon content from 9.7% to 31.9%. This result indicated the potential of the bifunctional catalyst in the field of lignin-oil valorization.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF MATERIALS SCIENCE
·
2023
·Vol. 58
·期 6
·2764-2781
·
IF 4.5
Zhang Xiangke,Chen Ming,Kan Yuping,Dong Yumeng,Zhang Xinyu,Wang Xueying,Su Hui,Xu Shiyi,Yan Xueying
A series of antitumor therapies such as chemotherapy, photothermal therapy, and photodynamic therapy have certain limitations when applied alone. Herein, the chemotherapy drug doxorubicin (DOX) and photosensitizer new indocyanine green (IR820) were loaded into mesoporous silica nanoparticles (MSNs), and it was wrapped by manganese dioxide (MnO 2 ) on the surface. Optimization of the synthesis conditions by Box–Behnken design (BBD) generated DOX-IR820@MSN–MnO 2 nanoparticles with a high loading capacity. The experiments suggested that the nanocomposites had tumor microenvironment response characteristics and excellent photodynamic and photothermal properties. It can significantly regulate the level of glutathione and reduce the antioxidant effect of cells to enhance the photodynamic effect. NIR laser irradiation increases the temperature and accelerates drug release. The relative cell viability in the multi-modal combination therapy group almost disappeared at 17.20%. Combined tumor microenvironment response and multi-modal therapy show unique advantages in inhibiting tumor cell proliferation and have promising applications and development potential in cancer treatment. Graphical Abstract
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2022
·
IF 5.532
Ruichong Chen,Hao Guo,Zhangyi Huang,Haomin Wang,Jianqi Qi,Mao Zhou,Wei Feng,Tiecheng Lu
Li 4 Si 1–x Ti x O 4 ceramic solid solution was considered as a promising tritium breeding material for fusion reactor blanket. In this work, the effects of the sintering atmosphere on the phase composition, microstructure, and mechanical properties of Li 4 Si 0.7 Ti 0.3 O 4 ceramic pebbles were investigated for the first time, aiming to explore the optimal sintering atmosphere for this solid solution. The results show that compared with air and argon atmosphere, the negative pressure of vacuum atmosphere was more favorable for Ti to enter the Li 4 SiO 4 crystal structure as a substitute for Si atom to form a solid solution. More importantly, sintering in argon-vacuum atmosphere can ensure the formation of solid solution while fully exerting the liquid phase sintering effect. The crushing load of the Li 4 Si 0.7 Ti 0.3 O 4 ceramic pebbles sintered at 800 °C in argon-vacuum atmosphere reaches 30.3 ± 3.2 N. In general, the appropriate sintering atmosphere was of great significance for obtaining Li 4 Si 0.7 Ti 0.3 O 4 solid solution to meet the performance requirements of tritium breeding blanket.
✓ 已验证
产品关联
DOI
高影响因子
Toxics
·
2023
·Vol. 11
·期 10
·860
·
IF 4.6
Yi Lu,Fangyuan Peng,Yingyang Wang,Haipu Li,Zhaoguang Yang
Antimony (Sb) is a non-essential metalloid that can be taken up by plants from contaminated soils and thus enter the food chain and threaten human health.Boehmeria niveaL. (ramie) is a promising phytoremediation plant for Sb-polluted soils. However, the mechanisms of antimonite (SbIII) and antimonate (SbV) uptake by ramie remain unclear. In this study, a hydroponic system was established to investigate how different substances affect the uptake of SbIII or SbV by ramie, including an energy inhibitor (malonic acid), an aquaglyceroporin inhibitor (silver nitrate), an SbV analog (phosphate—PV), and SbIII analogs (arsenite—AsIII, glycerol, silicic acid—Si, and glucose). The results indicated that ramie primarily transported Sb by increasing the Sb concentration in the bleeding sap, rather than increasing the weight of the bleeding sap. After 16 h of Sb exposure, the absolute amount of transported Sb from the roots to the aboveground parts was 1.90 times higher under SbIII than under SbV. The addition of malonic acid significantly inhibited the uptake of SbV but had limited effects on SbIII, indicating that SbV uptake was energy dependent. PV addition significantly reduced SbV uptake, while the addition of AsIII, glycerol, and Si obviously inhibited SbIII uptake. This suggested that the uptake of SbV might be via low-affinity P transporters and SbIII might use aquaglyceroporins. These findings deepen the understanding of Sb uptake pathways in ramie, contribute to a better comprehension of Sb toxicity mechanisms in ramie, and establish a foundation for identifying the most effective Sb uptake pathways, which could further improve the efficiency of phytoremediation of Sb-polluted soils.Keywords:ramie;antimony;uptake pathway;aquaglyceroporin
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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）