CONSTRUCTION AND BUILDING MATERIALS
·
2014
·
IF 2.265
Yu Liu,Xiaodong Zhu
Investigation of formaldehyde and VOCs emissions from wood-based panels are of great importance because of their negative impact on human health. In this study, a novel low formaldehyde and VOCs emitting board coated with nanomaterial-added melamine-impregnated papers was developed. Melamine resins which were reinforced with nanomaterials were used to impregnate decor papers. The effect of nanomaterial type (nano TiO 2 , nano MMT) and loading levels (0.5%, 1%) on formaldehyde and VOCs emissions from wood-based panels with melamine-impregnated papers were investigated. Formaldehyde and VOCs measurement were conducted according to GB 17657-1999 and JIS A1901-2009. Numerical results showed that formaldehyde and VOCs emissions from coating boards were significantly affected by nanomaterials. Compared with control panels, formaldehyde emissions from wood-based panels coated with 0.5% nanoparticles reinforced melamine-impregnated papers decreased slightly. With the increasing of loading level, the emissions decreased to a fairly low value, which were 22.2–36.6% lower than that of control panels. Most emitted VOCs were aromatics and alkane, which were main natural compounds detected in particleboard emissions. Most of the identified VOCs emissions decreased due to the existence of nanomaterial . With the increasing of nanomaterial loading level to 1%, total VOC emissions decreased 22.6–25.6% of control panels. This study provides a meaningful guidance on designing low-emitting wood-based panels with melamine-impregnated paper.
研究领域:
材料科学
·
室内空气质量
·
环境工程
·
木材科学与技术
✓ 已验证
DOI
高影响因子
COMPOSITES PART A-APPLIED SCIENCE AND MANUFACTURING
·
2023
·
IF 8.7
Junyu Lu,Haoruo Zhang,Mushan Yuan,Yunfei Gao,Mei Liang,Yang Chen,Huawei Zou
Without a reliable mechanical carrier, it is difficult to apply MA materials in realistic aerospace scenarios. Here, the broadband MA properties of RGO/melamine foam (RGO/MF) composites were prepared and optimized by hydrothermal chemical reduction method. The realization of broadband MA by RGO/MF is mainly achieved through the cooperative enhancement of RGO dispersion by the following two points: (1) three-dimensional (3D) meso -scale dispersion of RGO supplied by MF and (2) 3D microlayer separation of formed RGO provided by hydrothermal chemical reduction. For the first time, we successfully achieve complete filling of the RGO/MF into honeycomb. The RGO/MF honeycomb composites achieved almost 95.25 % EAB in the full frequency ranges from 2 to 18 GHz, where the MA performance of the composites originated from the electric-field loss of the RGO/MFs. Such RGO/MF honeycomb composites shows a promising application prospect and guidance in the field of aerospace stealth.
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2022
·
IF 16.744
Shansu Li,Wenjing Mo,Yuan Liu,Qi Wang
Taking serious electromagnetic pollution and practical application requirements into consideration, it’s imperative to develop multifunctional microwave absorption materials. In this work, the phenol–formaldehyde resin (PF) successfully adheres to melamine–formaldehyde foam (MF) as three-dimensional (3D) porous frameworks, and subsequently the substrate anchors few-layered MXene nanosheets by dripping-squeeze-drying procedures. According to the results, the hollow tent-like structure of MXene/PF@MF (MPM) shows a significant effect on microwave absorption capability, including extending heterogeneous interfaces for polarization relaxation and prolonging microwave propagation paths for energy dissipation. Based on the synergy of multiple components and rational structure, MPM exhibits a minimum reflection loss (RL min ) value of −58.8 dB at 2.2 mm and achieves an effective absorption bandwidth (EAB) of 6.74 GHz covering the entire Ku band. The microwave absorption mechanism reveals that the superior microwave absorption capability results from high conduction loss, polarization relaxation, multiple attenuations, and appropriate impedance matching. Furthermore, the MPMs possess lightweight features (32.7–48.7 g cm −3 ) and low thermal conductivity (0.0309–0.0318 W m −1 K −1 ) benefitting the unique 3D porous structure. Meanwhile, the low thermal conductivity endows MPMs with infrared stealth, which broadens the application in military fields. This work proposes a facile strategy for constructing highly efficient microwave absorbers with multiple functions.
✓ 已验证
产品关联
DOI
高影响因子
Journal of Environmental Chemical Engineering
·
2022
·
IF 7.968
Zhiyu Liu,Ye Li,Shuangshuang Peng,Ju Huang,Bolin Su,Kai Gao,Shuai Zhou,Zhaojian Gao,Teng Chen
In this work, 3D flowerlike Ag NPs/NiCo-layered double hydroxide (NiCo-LDH) decorated on melamine sponge was fabricated through a facile hydrothermal and in-situ reduction method. 3D flowerlike Ag NPs/NiCo-LDH were demonstrated to immobilize on the skeleton of polydopamine-pretreated melamine sponge. The melamine sponge decorated with 3D flowerlike Ag NPs/ NiCo-LDH presented outstanding catalytic activity for reduction of various water-soluble organic dyes in the appearance of NaBH 4 as reducing agent, including 4-nitrophenol (4-NP), rhodamine B (RhB), methylene blue (MB) and methyl orange (MO), respectively. Owing to the appearance of Ag NPs, the melamine sponge decorated with 3D flowerlike Ag NPs/NiCo-LDH also showed efficient antibacterial activities against Gram-positive Staphylococcus aureus and Bacillus cereus , and Gram-negative Escherichia coli and Pseudomonas aeruginosa , suggesting its broad-spectrum antibacterial property. Moreover, the melamine sponge decorated with 3D flowerlike Ag NPs/ NiCo-LDH could also achieve the separation process for insoluble oils/organics from water by a facile surface modification technology after being treated toward low-surface-energy chemical of octadecylamine. The octadecylamine-coated sponge exhibited superhydrophobicity (WCA=158.6°) and superoleophilicity (OCA=0°), which could adsorb a wide range of oils/organics without the adsorption of any water, thus realizing the process of oil/water separation. The novel comprehensive melamine sponge demonstrates a new strategy for the remediation of complex polluted water.
✓ 已验证
产品关联
DOI
高影响因子
FOOD CHEMISTRY
·
2022
·
IF 9.231
Xin Yue,Qiuli Pan,Jie Zhou,Hongxin Ren,Chifang Peng,Zhouping Wang,Yi Zhang
A novel lateral flow assay (LFA) was developed based on the aggregation induced emission (AIE) of gold nanoclusters (AuNCs) for the detection of melamine. We compared the interaction between melamine and AuNCs prepared with 6-Aza-2-thiothymine (ATT) and its four structural analogs as ligands and found that the ATT-AuNCs showed the best AIE induced by melamine. Then the ATT-AuNCs were directly immobilized on the test line of LFA strips as reporters. The sensing platform exhibited a linear response to melamine from 1 to 100 μM (R 2 = 0.997) with a detection limit of 217 nM. Moreover, this LFA strip could discriminate 1.0 μM melamine clearly by the naked eyes within 3 min. The recoveries of 91.6–101.5% were attained in milk and baby formula samples. This strip inherited the superior characteristics of low background interference of aggregation-induced fluorescence recognition and LFA technology, thus effectively avoiding the use of antibodies, aptamers, and other biological elements.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2023
·
IF 15.1
Wubo Wan,Zhuang Yang,Tao Tan,Yu Li,Zehao Zhang,Peng Zhang,Feng He
Herein, a melamine sponge is adopted as the skeleton to be modified by both methyl trichlorosilane (MTS) and polydimethylsiloxane (PDMS) on the surface, fabricating the 3D porous Mel@MTS/PDMS sponge. Systemic investigations reveal that MTS self-assembles into many micro-nano particles to roughen the surface of the melamine matrix, thus greatly increasing its hydrophobicity. PDMS tightly anchors those MTS particles via forming a surface coating. Therefore, the resultant Mel@MTS/PDMS sponge exhibits the superior oil-adsorbed capacity, good hydrophobicity, and great structural and mechanical stability. Based on this Mel@MTS/PDMS sponge, a consecutive oil/water separation system is successfully built and induces the continuous recovery of oil under various simulated oil–water separation conditions. Obviously, this 3D hydrophobic Mel@MTS/PDMS sponge and corresponding consecutive oil/water separation device provide a promising application strategy in the leaked oil recovery and environmental purification.
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF VINYL & ADDITIVE TECHNOLOGY
·
2023
·Vol. 30
·期 2
·456-469
·
IF 2.7
Zihao Wang,Jinheng Wang,Jianting Zhang,Weihong Guo
To address the flammability drawbacks of nylon 56 and expand the application range of bio-based nylon 56, melamine cyanurate (MCA) was employed through self-assembly in a solvent with graphitic carbon nitride surface treatment. Modified MCA (CNMCA)composition and morphology were investigated. CNMCA created with surface treatment and polyamide 56 (PA56) prepared with unmodified MCA had their flame retardant functions and mechanical properties investigated and compared. x-ray diffraction (XRD) and Fourier transform infrared (FT-IR) spectroscopy confirmed the successful microencapsulation of g-C 3 N 4 on the MCA surface. Further characterization of the unmodified MCA and CNMCA was performed using scanning electron microscopy (SEM). The SEM images revealed a significant reduction in the degree of agglomeration in CNMCA compared to conventional MCA, resulting in a more uniform dispersion in the PA56 matrix. Additionally, PA56/CNMCA achieved a UL94 V-0 rating and a limiting oxygen index (LOI) value of 30.1%. Notably, compared to pure PA56, PA56/CNMCA30 exhibited the most promising synergistic effect, leading to a separate reduction of 45.45% in the total heat release rate (THR) and 13.62% in the total smoke release (TSR). Consequently, with the same flame retardant addition (10 wt%), the CNMCA flame retardant showed superior dispersion in the bio-based nylon 56 matrix compared to traditional MCA. Due to the physical isolation of g-C 3 N 4 , the synergistic effect of MCA and graphitic carbon nitride imparted better mechanical properties and flame resistance to nylon 56. Highlights MCA/g-C 3 N 4 hybrids were prepared and applied in bio-based nylon 56 for the first time. The MCA/g-C 3 N 4 hybrid has better dispersion than MCA. PA56/MCA/g-C 3 N 4 flame retardant composites have better flame retardant and smoke suppression properties than PA56/MCA.
✓ 已验证
产品关联
DOI
高影响因子
POLYMER
·
2021
·
IF 4.43
Zhen Li,Yunfei Zhi,Yonghao Ni,Hongying Su,Yingju Miao,Shaoyun Shan
Copolymerization of SO 2 with epoxide into the poly(cyclohexene sulfite) (PCS) is crucial due to the severe harm of SO 2 to the environment and the wide application need of the PCS product. However, the copolymerization tends to exhibit low conversion rate even under harsh conditions. The introduction of high-efficiency catalysts is an efficient way to solve the problem of limitation of SO 2 copolymerization. Herein, the novel and metal-free Schiff-base network (SNW) material, SNW-KUST1, was successfully designed and structurally characterized, which exhibits an excellent catalytic performance for the copolymerization of SO 2 and cyclohexene oxide with a record PCS selectivity of 93%. In comparison with the SNW-1, the catalytic activity of SNW-KUST1 is greatly improved, which can be attributed to the introduction of hydroxyl and increasing specific surface area. Moreover, the SNW-KUST1 can be reused more than 6 times without obvious decrease of the catalytic activity, and presents a wide applicability to various epoxides. A possible mechanism for the SO 2 copolymerization over SNW catalysts is proposed which includes the epoxide adsorption, ring-opening of epoxide, SO 2 insertion and the formation of PCS. It is an optimistic hope that this investigation can give a valuable guideline to design SNW materials with π-π conjugated and nitrogen-rich building blocks for the SO 2 copolymerization.
✓ 已验证
产品关联
DOI
高影响因子
Forests
·
2021
·Vol. 12
·期 2
·127
·
IF 2.634
Qiangqiang Liu,Haojia Du,Wenhua Lyu
In order to improve the performance of soft plantation wood, an environmentally friendly wood modifier was developed. First, using urea and melamine as crosslinking agents, the glucose-urea-melamine resin (MUG) was prepared with glucose under the catalysis of inorganic acid and metal ions. Then MUG, sodium silicate, and distilled water were mixed and stirred at 40 °C to prepare MUG resin/sodium silicate compound modifier (G20S10, G10S20, the subscript number represents the mass percentage of the component in the solution.). Then plantation poplar wood (Populus tomentosa) was impregnated and modified with them. Their physical and mechanical properties were tested and compared with those of the wood treated with sodium silicate of 20% mass fraction (S20). Infrared analysis showed that the amino resin characteristic structure (CO-NH-) existed in MUG, and the absorption peak of the furan ring (C=C) appeared. Compared with S20modified wood, the shrinkage degree of G10S20or G20S10modified wood is reduced, their moisture absorption is decreased, and their dimensional stability is improved. MUG resin/sodium silicate compound modifier can effectively enhance the wood’s density, modulus of elasticity, modulus of rupture, and compression strength. SEM analysis showed that there were columnar and granular solid substances attached to the cell wall, cell lumen, intercellular space, and vessel of G20S10modified wood. EDX showed that the number of Si elements on the cell wall was significantly increased compared with the control, indicating that the modifier effectively entered the wood cell wall. The G20S10can greatly improve the wood’s physical and mechanical properties through an organic–inorganic compound synergistic effect. It is a green, non-formaldehyde, low cost wood modifier with broad application prospects.Keywords:poplar;glucose resin;sodium silicate;impregnation modification;wood properties
✓ 已验证
产品关联
DOI
高影响因子
MACROMOLECULAR MATERIALS AND ENGINEERING
·
2021
·Vol. 307
·期 2
·2100645
·
IF 4.367
Weiwang Chen,Sha Liu,Yueyan Sun,Xiaomeng Zhou,Fenglei Zhou
Polyimide aerogels are promising for diverse applications owing to their nano-porous structure and superior properties. However, the shrinkage of melamine-crosslinked polyimide (MPI) aerogels has greatly compromised their performance in practical applications. In this study, supercritical drying with ethanol rather than CO 2 is employed to enhance their in-use shape stability at high temperatures. The structure, thermal insulation, mechanical strength of the resultant aerogels as well as their shape stability are characterized. Experimental results reveal that the shape stability of MPI aerogels during use is greatly improved thanks to the in-advance baptism of supercritical ethanol drying. The aerogel shrinks by only 2.64 vol.% after being treated at 280 °C for 72 h. Besides, the MPI aerogel shows enhanced compressive strength and can easily support a load more than 20 000 times its own weight. The thermal conductivity of these aerogels varies from 0.034 to 0.046 W m −1 k −1 , indicative of remarkable performance in thermal insulation. In addition, the aerogels that started to decompose at as high as 500 °C also perform well in thermal stability and char forming. It can be envisaged that the developed MPI aerogels with greatly improved in-use shape stability may have broad prospects for thermal insulation at high temperatures.
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2021
·
IF 6.953
Xiang Li,Wen Zhang,Meng Wu,Sheng Li,Xiaoli Li,Zhiguo Li
A facile synthesis strategy by combination self-activation of biomass materials with heteroatom dopant in one-step is developed to fabricate porous carbons (NO-PCMs) doping with N, O, and S elements from direct carbonization of sodium lignosulfonate and melamine mixture. Two different types of active defects are constructed simultaneously through the decomposition of sodium lignosulfonate in NO-PCMs, exhibiting hierarchical porosity and abundant heteroatoms contents. The typical NO-PCMs displayed high specific capacitance (300 F g −1 at 0.1 A g −1 ) and outstanding cycling stability (99% capacitance retention after 10,000 charge/discharge cycles at 10 A g −1 ) in 6 M KOH electrolyte. Furthermore, the assembled symmetric supercapacitors exhibited high specific capacitance of 162 F g −1 at 20 A g −1 , 71% capacitance retention at current density up to 20 A g −1 , and possessed high specific energy density of 21.6 Wh kg −1 with an excellent power density of 92 W kg −1 operated in the wide voltage range of 1.8 V in 1 M Na 2 SO 4 aqueous electrolyte, demonstrating the broad prospects of biomass/biowaste being used to prepare electrode materials.
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF ELECTROANALYTICAL CHEMISTRY
·
2021
·
IF 4.464
Qing Wang,Zihan Zhang,Shaojie Shi,Fan Wu,Zhiguo Zhang,Guoneng Li,Yange Suo
In this work, highly active cobalt- and nitrogen-doped carbon (Co-N-C) materials were prepared for oxygen reduction reaction (ORR). The Co-N-C materials were synthesized through co-pyrolysis of ZIF-67 and melamine (ZIF-67@melamine). Detailed powder X-ray diffraction (XRD), fourier transform infrared (FTIR) spectroscopy and thermo-gravimentry (TG) analyses suggest melamine could accelerate the decomposition of the ZIF-67 framework. Compared with CoNC derived from pure ZIF-67, the CoNC- x C 3 H 6 N 6 materials derived from ZIF-67@melamine exhibit more carbon defects, larger BET specific surface area, higher content of pyridinic-N and graphitic-N, resulting in the enhanced activity of the CoNC- x C 3 H 6 N 6 samples. The onset potential of CoNC-0.5C 3 H 6 N 6 -700 catalyst towards ORR is 0.96 V (vs. RHE) and the half-wave potential is 0.87 V (vs. RHE), which are close to the state-of-the-art commercial Pt/C. Besides, the electrochemical stability of the CoNC-0.5C 3 H 6 N 6 -700 catalyst is much higher than that of commercial Pt/C.
✓ 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）