ATMOSPHERIC ENVIRONMENT
·
2020
·
IF 4.039
Yaxin Guo,Na Wang,Shufeng Pang,Yunhong Zhang
Although nitrates and amino acids are ubiquitous in the atmosphere, the interactions of amino acids with nitrates on the hygroscopicity of aerosols are still not clear. We studied the hygroscopic properties and compositional evolution of three atmospherically relevant species, sodium nitrate (NaNO 3 ), glycine and L-alanine (alanine). The investigations on the NaNO 3 , glycine, alanine and their internally NaNO 3 /amino acid mixed particles with molar ratios of 3:1, 1:1 and 1:3 were conducted using attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR). The mixed NaNO 3 /glycine droplets with molar ratios of 3:1, 1:1 and 1:3 exhibited efflorescence transition at 52.3%, 62.6% and 63.2%RH, respectively. For the NaNO 3 /alanine mixed systems with molar ratios of 3:1, 1:1 and 1:3, the efflorescence relative humidity (ERH) was measured to be 50.2%, 59.8% and 69.3%, respectively. These results suggested that in each of the systems studied the addition of amino acids to aerosols could promote the crystallization of mixed droplets. However, the higher deliquescence relative humidity (DRH) with increased fraction of glycine for the mixed NaNO 3 /glycine (3:1, 79.2%RH; 1:1, 86.3%RH; 1:3, 86.5%RH) also indicated that glycine could inhibit the deliquescence phase transition of mixed systems. In the case of NaNO 3 /alanine systems, the DRH for 3:1 and 1:3 mixed particles was 78.2% and 82.7% while no deliquescence transition occurred for the 1:1 mixed particles. The hygroscopic properties of mixed NaNO 3 /amino acids droplets were modified due to the formed amino acid-NaNO 3 complex salts from the interactions of amino acids with NaNO 3 in aerosols during dehydration process. The discrepancies in water content for the mixed NaNO 3 /amino acids with molar ratios of 1:1 and 1:3 between dehydration and hydration processes at high RH could be attributed to the crystallization of amino acid-NaNO 3 complex salts during dehydration and the residual amino acids.
研究领域:
大气科学
·
化学
✓ 已验证
DOI
高影响因子
Energetic Materials Frontiers
·
2021
·
IF 0
Rong-rong Yang,Chang-kun Song,Ya-jie Chen,Guo-wei Zeng,Jia-xin Wang,Jun-hong Chen,Wen-chao Zhang
The large energy release potential and highly adjustable combustion characteristics of nanostructured silicon compounded with sodium perchlorate (NaClO 4 ) make it one of the most attractive inorganic energetic materials. Compared with nanoporous silicon, the silicon nanowires prepared by metal-assisted chemical etching are easily loaded with NaClO 4 to obtain energetic materials, due to their one-dimensional array structure and tight contact with the silicon substrate. However, the high hygroscopicity of NaClO 4 greatly degrades the long-term storage property of the material, and must be addressed. In this study, sulfur, as a known stable and non-hygroscopic oxidant that reacts with nanostructured silicon, was impregnated on the silicon nanowires/NaClO 4 energetic material to insulate NaClO 4 from H 2 O in the ambient air. After sulfur impregnation, the mass of the sample increased by 8.7 mg after being exposed to 98% relative humidity at 25 °C for 12 h, while the sample without sulfur increased by 50 mg, indicating significant improvement in the hygrophobicity of the sulfur-containing energetic material. Laser ignition experiments showed that the combustion performance was only slightly affected after sulfur treatment. This work provides a new strategy for improving the hygrophobicity of silicon-based energetic materials, which can improve their applicability in micro-electromechanical systems.
研究领域:
材料科学
·
能源工程
✓ 已验证
DOI
Crystals
·
2019
·Vol. 9
·期 12
·675
·
IF 2.061
Jinbo Ouyang,Jian Chen,Limin Zhou,Fangze Han,Xin Huang
To improve the physicochemical properties of valnemulin (VLM), different solid forms formed by VLM and organic acids, including tartaric acid (TAR), fumaric acid (FUM), and oxalic acid (OXA), were successfully prepared and characterized by using differential scanning calorimetry (DSC), scanning electron microscope (SEM), X-ray powder diffraction (XRPD), and Fourier-transform infrared spectroscopy (FT-IR). The excess enthalpyHexbetween VLM and other organic acids was calculated by COSMOthermXsoftware and was used to evaluate the probability of forming multi-component solids between VLM and organic acids. By thermal analysis, it was confirmed that multi-component solid forms of VLM were thermodynamically more stable than VLM itself. Through dynamic vapor sorption (DVS) experiments, it was found that three multi-component solid forms of VLM had lower hygroscopicity than VLM itself. Furthermore, the intrinsic dissolution rate of VLM and its multi-component forms was determined in one kind of acidic aqueous medium by using UV-vis spectrometry. It was found that the three multi-component solid forms of VLM dissolved faster than VLM itself.Keywords:valnemulin;solid forms;dissolution rate;hygroscopicity
研究领域:
药学
·
物理化学
✓ 已验证
产品关联
DOI
高影响因子
COMPOSITES SCIENCE AND TECHNOLOGY
·
2015
·
IF 3.569
Biao Zhang,Feng Ye,Ye Gao,Qiang Liu,ShiChao Liu,Limeng Liu
Bisphenol-A cyanate ester resin (BADCy)/Ni 0.5 Ti 0.5 NbO 4 composites with novel structure, within which Ni 0.5 Ti 0.5 NbO 4 and BADCy are continuous directional distribution and parallel to the electric field direction (marked as composite-directional), were designed and fabricated using freeze casting combined with vacuum assisted infiltration process. Dielectric properties as well as the moisture absorption of the composites were studied. Theoretical models used to predict the dielectric properties of the composites were established. Results show that the novel structure can significantly improve the dielectric constant while decrease dielectric loss compare with traditional structure in which Ni 0.5 Ti 0.5 NbO 4 filler is homogeneously distributed (the composite marked as composite-homogeneous). Dielectric constant of composite-directional is as high as 19.93 while dielectric loss is only 4.07 × 10 −3 (at 7319 MHz) when Ni 0.5 Ti 0.5 NbO 4 content is 43.79 vol%. Furthermore, the dielectric constant of both composite-directional and composite-homogeneous can be predicted using Rother-Lichtenecker model when the fitting parameters ( n ) are −0.5188 and −0.1499, respectively. Distribution state of Ni 0.5 Ti 0.5 NbO 4 is the main reason for the difference of fitting parameters. Due to the excellent properties of composite-directional, this kind of composites can be used as printed circuit board (PCB) materials.
研究领域:
材料科学
·
电子工程
✓ 已验证
产品关联
DOI
高影响因子
Additive Manufacturing
·
2024
·
IF 10.3
Lu Yang,Jiaguang Meng,Tao Xue,Yongzhen Wang,Gege Shi,Xingyun Gao,Chao Zhi
3D printing technology is highly regarded in the textile and apparel industry for its rapid manufacturing and customization capabilities. However, the current 3D printing materials employed in this field can limit printed fabrics with restricted flexibility and comfort, creating a notable disparity compared to traditional textiles. To address this limitation, the study focuses on utilizing cotton fibers as the raw material for 3D printing textiles. Herein, cotton fibers were dissolved in a LiCl/DMAc solvent, with the incorporation of hydroxyethyl cellulose to adjust the printability of the ink. Materials extrusion technique was employed for the printing process. This work involved optimizing dissolution, adjusting ink viscosity , and selecting post-processing methods for the printed fabrics. A comparative investigation of the wear properties of printed cellulose fabrics, cotton fabrics, and 3D printed fabrics from thermoplastic materials was conducted. The results indicate improvements in the flexibility, breathability, and moisture absorption of 3D printed cellulose fabrics compared to existing 3D printed fabrics. Additionally, these 3D printed cellulose fabrics demonstrate superior abrasion resistance when compared to cotton fabric. As a proof of concept , garments and gloves were successfully prepared using 3D printed cellulose fabrics, expanding the use of textile materials in 3D printed textiles. This innovative approach holds promising prospects for 3D printing flexible fabrics and garments.
研究领域:
纺织科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF DRUG DELIVERY SCIENCE AND TECHNOLOGY
·
2022
·
IF 5.062
Lixin Liu,Qi An,Yunan Zhang,Weitong Sun,Jinjing Li,Yanru Feng,Yiding Geng,Guangdong Cheng
With the purpose of improving the solubility and reducing the hygroscopicity of enrofloxacin (ENR), an unreported pharmaceutical salt cocrystal of enrofloxacin with both neutral and anionic p-nitrobenzoic acid (PNB) (ENR-PNB, C 19 H 23 FN 3 O 3 ·C 7 H 4 NO 4 ·C 7 H 5 NO 4 ) was designed and synthesized by changing the reaction molar ratio (1:2) of ENR and coformer PNB on the basis of summarizing the past experience of our group, and its crystal structure was characterized. Single-crystal X-ray diffraction (SCXRD) analysis revealed that the salt cocrystal consists of ENR + , PNB − and PNB neutral molecule in a 1:1:1 ratio. The two asymmetric units that become centrosymmetric form an X-shaped structure centered on the ENR dimer R 2 2 (20). The adjacent X-shaped structures are interconnected by hydrogen bonds to form 1D chain and form the octamer R 8 8 (42) at the same time. As we expected, the formation of the salt cocrystal ENR-PNB results in a simultaneous improvement in the solubility and hygroscopicity of ENR. This may be the fact that ENR and PNB depend on CAHBs to raise the hydrous enthalpy of salt cocrystal. And the presence of PNB neutral molecules lower hygroscopicity of ENR in high humidity environments. Unexpectedly, the permeability of ENR-PNB was also increased compared to that of pure ENR. It is speculated that the number of polar sites in the system is greatly reduced because of hydrogen bonds formation, which increases the permeability of the ENR salt cocrystal. In addition, the in vitro antibacterial activities of ENR-PNB are enhanced at different concentrations compared to ENR. The present study implies that it is possible to improve the solubility, hygroscopic stability, permeability and antibacterial activity of enrofloxacin by changing the chemical reaction molar ratio to form salt cocrystal containing both neutral and anionic coformers, which provides a new strategy and insight to simultaneously improve the solubility and hygroscopicity and even permeability of the active ingredients of solid drugs.
研究领域:
药物化学
·
晶体学
✓ 已验证
产品关联
DOI
高影响因子
STAR Protocols
·
2023
·
IF 0
Zhipeng Luo,Jiayun Wang,Yu Pan,Peng Gao,Hua Zhang,Ruzhu Wang
Summary Desiccant-coated heat exchangers provide a practical solution for the efficient removal of moisture from the air. Here, we present a protocol to synthesize an ultra-hygroscopic polymer to develop a LiCl loaded in curdlan hydrogel (LiCl@Cur)-coated heat exchanger for deep dehumidification. We describe steps for preparing the curdlan gel solution, hydrogel, LiCl solution, and LiCl@Cur. We then detail procedures for preparing curdlan-coated and LiCl@Cur-coated heat exchangers. The coated heat exchanger described in this protocol has a maximum dehumidification capacity of 12 g/kg. For complete details on the use and execution of this protocol, please refer to Pan et al. (2023). 1
研究领域:
材料科学
·
环境工程
✓ 已验证
DOI
PubMed
NEW JOURNAL OF CHEMISTRY
·
2021
·Vol. 45
·期 48
·22860-22868
·
IF 3.591
YiFan Chen,Lei Ding,Chao Cui,Zhengxiang Zhong,Li Liu,Yudong Huang
A simple method to prepare an emulsifier was proposed to form a stable nano size emulsion as a sizing agent to enhance the interfacial bonding strength between carbon fiber (CF) and epoxy resin. The toluene diisocyanate (TDI) grafting strategy can effectively introduce hydrophilic polyethylene glycol (PEG) and hydrophobic poly(propylene glycol) (PPG) into the side chain of the epoxy resin without consuming epoxy groups. The PPG chain segment length was controlled to improve the stability of the emulsion. An emulsion prepared with EP–PEG6000–PPG2000 (EE-P20) as the emulsifier had the highest stability, and could be placed for more than 6 months without changes in the droplet size. The wettability of CF modified by this sizing agent was obviously improved, and the interfacial shear strength (IFSS) and interlaminar shear strength (ILSS) of CF(EE-P20) were increased by 42.33% and 17.41%, respectively. It was worth noting that the moisture absorption of CF(EE-P20) was 3.12% at 90% relative humidity. The introduction of the PPG segment not only improved the storage stability of the emulsion, but also improved the moisture resistance of CF after sizing. This simple continuous grafting method provides a new idea for adjusting the structure of the epoxy sizing agent, and the obtained emulsifier has a wide application prospect in the field of the CF sizing agent.
研究领域:
材料科学
·
复合材料
✓ 已验证
DOI
高影响因子
CELLULOSE
·
2021
·Vol. 28
·期 11
·7273-7282
·
IF 5.044
Yuan Jing,Chen Qi,Fang Changhua,Zhang Shuqin,Liu Xianmiao,Fei Benhua
Despite the robust mechanical properties of bamboo, interaction with water can result in the instability of these properties. Hygroscopicity is closely related to the chemical content of bamboo. Here, we explored the influence of the chemical composition of bamboo on moisture content from both the equilibrium state and dynamic aspects. We used a simple manufacturing separation process to obtain bamboo fibers (C). A chemical treatment was then used to remove the lignin and hemicellulose, thus altering the chemical content and exposing a greater number of functional groups. We obtained the RL (partial lignin removal) sample via the removal of lignin and the RLH (partial lignin and hemicellulose removal) sample via the removal of lignin and hemicellulose, respectively. The characteristics of the samples were tested using scanning electron microscope, infrared spectrometer and X-ray. And then the hygroscopicity was tested. At 90% relative humidity, the removal of the lignin reduced the weight by 13.30 wt% and increased RL moisture content by 2.99%, while the removal of lignin and hemicellulose reduced the RLH moisture content by 1.94%. At low humidity, RL and RLH have similar hygroscopicity. The RLH sample exhibited the lowest hysteresis out of all the samples. The lignin exhibited an obvious inhibitory effect on the hygroscopicity, while the presence of hemicellulose increased the moisture content of the materials, which is not conducive to their dimensional stability. Moreover, the hygroscopicity of cellulose and hemicellulose is similar. In particular, the chemical-treated samples responded more sensitively and quickly to water through dynamic changes in the weight of the water.
研究领域:
材料科学
·
植物学
✓ 已验证
DOI
高影响因子
ATMOSPHERIC ENVIRONMENT
·
2022
·
IF 5.755
Na Wang,Yaxin Guo,Jiarong Li,Shufeng Pang,Yunhong Zhang
Water-soluble amino acids have been confirmed as effective cloud condensation nuclei (CCN) materials. While their influence on the hygroscopicity of nitrates is still scarcely known. In this work, ammonium nitrate (AN) was mixed with glycine and alanine at various mole ratios to form internally mixed particles deposited onto a solid substrate, whose hygroscopic properties and phase states of ingredients were investigated using microscope and attenuated total reflection-Fourier transformed infrared spectroscopy (ATR-FTIR). For mixed AN/amino acid particles with abundant inorganic, AN crystallizes at lower RH than that of pure AN, while deliquescence relative humidities (DRHs) were close to pure AN. On hydration, the mixture composed of bis(amino acid) nitrates and mono(amino acid) nitrates formed at 14.6–60.8% RH and 23.6%–60.0% RH for AN/glycine and AN/alanine particles, respectively. When the inorganic and organic components were mixed with equal mole ratio, gradual water uptake and release took place due to the hygroscopic interplay between components. In the mixed particles with abundant amino acids, glycine and alanine still kept solid at highest RH on hydration. Hydrogen bonding interaction should account for the mutual suppression on individual crystal formation. The present hygroscopic study would help people understanding cloud condensation nuclei (CCN) ability of amino acids in atmosphere.
研究领域:
大气科学
·
化学
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2015
·
IF 2.605
Biao Zhang,Feng Ye,Ye Gao,Shichao Liu,Qiang Liu,Donghai Ding
Ni 0.5 Ti 0.5 NbO 4 was firstly reported as filler to adjust dielectric properties of polymer matrix composites for printed circuit board (PCB) application. In this study, the Ni 0.5 Ti 0.5 NbO 4 filler was modified using γ-aminopropyl triethoxy silane (KH550). The effects of KH550 on particle lipophilicity and Bisphenol-A cyanate ester resin (BADCy) curing behavior were studied. BADCy/Ni 0.5 Ti 0.5 NbO 4 composites were fabricated by the traditional casting method. The dielectric properties and moisture absorption of the composites were tested. Results show that most hydrophilic groups on the surface of Ni 0.5 Ti 0.5 NbO 4 powder are replaced by lipophilic groups after modification, which results in the obvious improvement of Ni 0.5 Ti 0.5 NbO 4 filler dispersion in BADCy. Beyond that, surface modification also greatly affects the curing behavior of BADCy resin. The BADCy/Ni 0.5 Ti 0.5 NbO 4 -KH550 composites exhibit excellent dielectric properties as well as low moisture absorption. Furthermore, the dielectric constant can be accurately predicted using Effective Medium Theory (EMT model) when the morphology factor is 0.1407.
研究领域:
材料科学
·
电子工程
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF BIOLOGICAL MACROMOLECULES
·
2023
·
IF 8.2
Xinhong Han,Yiwen Xue,Rui Lou,Shaoqiu Ding,Shurong Wang
Sorption dehumidification, as an energy-saving and eco-friendly approach, has been emerging in application for air dehumidification. Here, a prospective method is proposed to prepare biomass-based hygroscopic aerogels that are easily applicable, sustainable, high-efficient, and recyclable. The chitosan-based aerogel with a porous and hydrophilic network acts as the carrier and water reservoir for the uniformly distributed lithium chloride hygroscopic salt, and provides the hygroscopic salt with more liberal water channels to facilitate moisture capture and transfer. As a consequence, the prepared chitosan/polyvinyl alcohol@lithium chloride (chitosan/PVA@LiCl) hygroscopic aerogel exhibits an excellent moisture absorption capacity of up to 2.77 g g −1 at a relative humidity of 90 %. Meanwhile, as the chitosan/PVA@LiCl aerogel is set in a closed space about 2200 times larger than its own volume, the relative humidity can be reduced from 90 % to 32 % within 2 h, and further lower to 25 % after 4 h. Furthermore, combined with multi-walled carbon nanotubes, the photothermal hygroscopic aerogel is obtained that can rapidly desorb water under sunlight, thus to realize energy-free cycle. Overall, the renewable biomass-based aerogel materials with the advantages of simple preparation and excellent hygroscopic performance provides a new path for the development of sorption dehumidification technology.
研究领域:
材料科学
·
环境工程
✓ 已验证
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）