JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY
·
2020
·
IF 4.192
Kai Li,Qingming Luo,Juan Xu,Kun Li,Wenwen Zhang,Lanxiang Liu,Jinju Ma,Hong Zhang
Renewable biobased porous aerogels with excellent biodegradability have versatile applications in oil/water separation, catalysis, and tissue engineering. However, processing of the porous matrix is challenging due to the high energy consumption and low efficiency from the fabrication procedures, such as freeze-drying or critical-drying of the hydrogel, which need to be improved. In the present study, natural amphiphilic oligomer shellac secreted by the lac Kerriar Lacca insect was employed to fabricate the porous template, which could self-assemble into a continuous rigid network with a hydrophobic core. Because of the hydrophobic core, the hydrated shellac network could be directly dried without collapse by the ambient air. The air-drying shellac aerogel presented a great mechanical property. The silane-coating treatment converted this shellac aerogel into a hydrophobic material that absorbed various organic solvents and oils. Also, this silane-coated shellac aerogel also could remove organic solvent or oil from the bottom or surface of the water. Notably, the saturable aerogel rapidly degraded in pH 14 and released the solvent absorbed by this matrix. This porous and hydrophobic matrix also could be applied as a filter that could connect with a vacuum pump to assemble a device for continuous collecting of oil from water. It also has great potential to be employed as a high-efficiency strategy to treat large scale oil spill issues. A new porous template composed of natural resin secreted by the insect was fabricated, and the whole fabrication process was green, low-cost, and energy saving. The surface of this template could be modified further to effectuate other processes, such as catalysis, heavy metal absorption, and tissue proliferation.
研究领域:
材料科学
·
环境科学
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF NON-CRYSTALLINE SOLIDS
·
2022
·
IF 4.458
Wei Dang,Bowen Wang,Zhuoli Xu,Xinyuan Zhang,Fuping Li,Kang Zhao,Xu Hu,Yufei Tang
ZrO 2 nanofiber aerogels with carbon as fiber junction were fabricated by freeze drying. The effects of resorcinol-formaldehyde (RF) content and fiber content on the pore structure , thermal property and compressive property of ZrO 2 /C nanofiber aerogels were systematically investigated. ZrO 2 /C nanofiber aerogels have ultra-high porosity above 99.4%, and possess hierarchical pore structure with honeycomb pores in the micro-scale and minor pores in the nano-scale. Both RF content and fiber content have effects on the porosity, thermal conductivity and plateau stress of ZrO 2 /C nanofiber aerogels. Thermal conductivity is in the range of 0.0332–0.036 W·m −1 ·K −1 . With the increase in RF content or fiber content, both thermal conductivity and plateau stress increase. The thermal transfer mode and compressive deformation mode were analyzed. Fiber junctions play a significant role during the thermal transfer and compression of ZrO 2 /C nanofiber aerogels.
研究领域:
材料科学
·
热力学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
·
2025
·
IF 6.2
Heng Zhang,Dongxu Yao,Ming Zhu,Yongfeng Xia,Jun Zhao,Yu-Ping Zeng
Porous Si 3 N 4 ceramics hold great promise for high-temperature wave-transparent materials, but it is a significant challenge to achieve both a low dielectric constant and high mechanical strength. This study explores a method combining in-situ pre-gel casting and non-directional freeze-drying to produce high-porosity, uniform microstructure Si 3 N 4 ceramics. By adjusting gel concentration and pre-gelation time, ice crystal growth effectively restricted, resulting in a uniform pore structure. The resulting porous Si 3 N 4 ceramics exhibited low drying shrinkage (1.50 %) and high porosity (59.13 %), with a flexural strength of 119.48 MPa, surpassing porous ones produced by other wet forming processes. At 30 GHz, the dielectric constant was 2.45, and the dielectric loss was 5.65 × 10 −3 .
研究领域:
材料科学
·
陶瓷工程
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2024
·
IF 8.1
Huiao Liu,Yan Li,Ziying Hu,Xinhui Hao,Hongpeng Jia,Jing Chen,Can-Zhong Lu
A wire like CeO 2 catalyst (CeO 2 -w) was obtained after the calcination of the precursor at 400 °C, which was prepared by the freeze-drying method for the first time. It shows good performance for catalytic oxidation of toluene with T 90 of 220 °C, which is much better than the CeO 2 catalysts with other structures prepared by the different methods. The good performance of CeO 2 -w is due to the bigger pore volume, more active oxygen species, more oxygen vacancies, better low temperature reducibility, higher surface area normalized reaction rates and lower E a value. Additionally, the CeO 2 -w catalyst exhibits good water resistance and catalyst stability. In situ DRIFTS indicates the catalytic oxidation of toluene on CeO 2 -w undergoes the progress of toluene → benzaldehyde → benzoic acid → maleic acid → CO 2 and H 2 O. This work affords a new idea to prepare high active CeO 2 nanowire catalysts for catalytic oxidation of toluene, and open an efficient way for the construction of CeO 2 based composite catalysts for VOCs degradation.
研究领域:
材料科学
·
环境科学
✓ 已验证
DOI
高影响因子
POLYMER ENGINEERING AND SCIENCE
·
2025
·
IF 3.2
Bing Xu,Dehua Pan,Yue Yu,Ziyang Zhou,Jie Hu,Wuqi Wen,Shui He,Guozhi Fan
Developing lightweight materials that combine low drying shrinkage with highly anisotropic thermal conductivity remains a key issue that must be addressed to meet the special requirements of integrally formed nose cones applied in hypersonic aircraft, which must achieve efficient windward (i.e., axial) insulation and enable heat dissipation perpendicular to the windward direction (i.e., radial) simultaneously. The present work employs unidirectional freeze-drying combined with molecular bonding engineering strategies to enhance the anisotropic structure of the polyimide (PI). By innovatively introducing a trace amount (only 1 wt%) of aminated glass fibers (GF) to construct multiple robust structural anchors, the network structure is significantly reinforced, yielding a high-performance PI/GF aerogel composite to address this challenge. The PI/GF aerogel composite exhibits an ultra-low density of 0.01 g/cm 3 and a drying shrinkage of only 1.75%. The axial compressive strength of the PI/GF aerogel composite materials reaches up to102.1 KPa. Finally, the PI/GF aerogel composites demonstrate significantly lower thermal diffusivity perpendicular to the freezing direction (radial direction, 0.601–3.680 mm 2 /s) than that observed parallel to the freezing direction (axial direction, 2.074–13.182 mm 2 /s) owing to pronounced morphological anisotropy, where a lamellar porous structure in the radial direction contributes to its superior thermal insulation performance. These results demonstrate that the proposed composites represent advanced thermal protection materials appropriate for hypersonic aircraft.
研究领域:
材料科学
·
航空航天工程
·
热工学
·
聚合物复合材料
·
纳米材料
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2019
·
IF 6.361
Yi He,Xin Zhang,Yuxiang Zhong,Xue Li,Lailei Wu,Hanyu Liu,Huiyang Gou,Gongkai Wang
Transparent and flexible supercapacitors (TFSCs) could diversify the future wearable electronics owing to the fascinating optoelectronic and electrochemical performances . Herein, we report symmetric TFSCs assembled by reduced graphene oxide (rGO)@Ag nanowire/poly (ethylene terephthalate) (PET) transparent electrodes for capacitive storage, in which the interfacial structure of rGO film can be tuned by a facile freeze drying technique. The enlarged interlayer spacing of rGO film deteriorated the electronic migration derived from the loose layer structure, whereas about 33–52% of the areal capacitance of TFSCs was boosted as compared with the ones without freeze drying at the same transmittance . It is concluded that the enlarged inter-distance of rGO film could facilitate diffusion and transport of ions in the electrolyte, furthermore, the expanded rGO film could provide more interface to accommodate more ions for storage. The simulation results also confirmed the lower diffusion barrier and larger band gap of rGO with larger interlayer distance. The mechanically robust TFSCs exhibit the maximum energy density of 89.2 nWh cm −2 , and the maximum power density of 4.63 μW cm −2 with remaining energy density of 41.1 nWh cm −2 , as well as 3000 cyclic stability, demonstrating an efficient strategy toward high performance TFSCs.
研究领域:
材料科学
·
能源存储与转换
✓ 已验证
产品关联
DOI
PubMed
高影响因子
FOOD CHEMISTRY
·
2018
·
IF 4.946
Yang Chen,Zong-cai Tu,Hui Wang,Guang-xian Liu,Zi-wei Liao,Lu Zhang
In general, the reducing sugars were extensively utilized as additives to prevent denaturation and inactivation during the freeze-drying process. However, different additives have unequal protective effects on the protein conformation. To evaluate the mechanism of protection the protein structure using different additives in the freeze-drying process, the glycated sites and degree of substitution per peptide (DSP) of each site were investigated by LC-Orbitrap MS. We found that the ovalbumin that was supplemented with ribose and then lyophilized (R-oval) have the highest extent of glycation modification. K227 was the most reactive glycated site in R-Oval, with a DSP of 0.83. The ovalbumin that was supplemented with lactose and then lyophilized (L-Oval) have the lowest degree of glycation, and K227 did not undergo the glycation reaction. It was hypothesized that the order impact of different additives on protection of the protein conformation were lactose > galactose > ribose during the freeze-drying process.
研究领域:
分析化学
·
蛋白质化学
·
药学
✓ 已验证
DOI
PubMed
高影响因子
Materials Today Communications
·
2024
·
IF 3.7
Zihe Hu,Gaoying Hong,Mumian Chen,Yanyan Zhou,Haiyan Wu,Weiying Lu,Minghao Zuo,Zhijian Xie,Changyu Shao,Jue Shi
Excessive blood loss caused by natural accidents or major surgical procedures can be life-threatening and requires rapid hemorrhage management. Developing hemostatic materials with high water absorption capacity and high strength properties is still challenging. Super hydrophilic/high-strength chitosan hemostatic sponges (SHHS-CHS) were prepared by freeze-drying and alkali treatment. The freeze-drying technology formed a porous three-dimensional structure of sponges, and alkali treatment increased the hydrophilicity of sponges and the rigidity of the chitosan molecular chain, improving the hydrophilicity and mechanical properties of chitosan sponges. Characterization experiments revealed that SHHS-CHS had high water absorption capacity, rich pore structure, and excellent mechanical properties. The cytotoxicity and hemolysis experiments showed that SHHS-CHS had good biocompatibility. Compared to the commercial hemostatic gelatin sponges and chitosan hemostatic material, SHHS-CHS had better blood coagulation and red blood cell and platelet adhesion ability. Moreover, SHHS-CHS showed better hemostatic ability than gelatin sponges in rat-liver injury and rat leg vein rupture models, significantly reducing the hemostasis time and bleeding volume. In conclusion, SHHS-CHS has broad prospects for clinical application as a hemostatic material.
研究领域:
材料科学
·
生物材料
·
止血
·
生物医学工程
✓ 已验证
产品关联
DOI
高影响因子
POLYMER COMPOSITES
·
2022
·Vol. 44
·期 3
·1648-1657
·
IF 3.531
Qingtao Lv,Jingfeng Yang,Xin Sun,Hui Tang,Lixin Wang
The development of high-performance energy-saving insulation materials is significant for reducing building energy consumption and promoting carbon neutrality. Aerogels show great potential in energy-saving insulation. However, their high preparation cost and poor mechanical properties limit their application. Here, based on a simple freeze-drying strategy, a halloysite nanotubes (HNTs)/polyvinyl alcohol (PVA) composite aerogel is achieved via low-cost and degradable industrial raw material. In particular, a simple process for changing the properties of HNTs/PVA composite aerogels by regulating the solid concentration. As a result, stable covalent cross-linking and hydrogen bonding structure between HNTs and PVA, long-range ordered pore structure with high porosity (97.6%), low density (0.12 g/cm 3 ), and low thermal conductivity (44.333 mW/m K) endow the HNTs/PVA composite aerogel high compressive strength (3.33 MPa), lightweight, and highly efficient thermal insulation properties. This work offers an attractive material for building insulation and carbon neutral.
研究领域:
材料科学
·
能源工程
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL JOURNAL OF FOOD SCIENCE AND TECHNOLOGY
·
2023
·
IF 3.3
Longbin Zhong,Zihuan Fu,Xinpeng Bai,Hengwei Zhu,Peng Zhu,Huan Huang,Yizhe Liu
Summary Converting craft beer to a powder form allows the concentration of phenolic and volatile compounds. In this study, craft beer was brewed in laboratory brewing equipment and converted to a powder using freeze-drying and spray-drying processes. When the freeze-dried powder was dissolved in water, its physicochemical properties were identical to those of craft beer. Freeze-drying effectively encapsulated the bioactive compounds in craft beer, with an encapsulation rate of 99.6%, which was 27.6% higher than that of spray-drying. Headspace solid-phase microextraction coupled to gas chromatography–mass spectrometry analysis revealed that the esters were effectively retained after freeze-drying and had the highest retention of 90% for ethyl hexanoate, whereas spray-drying resulted in the loss of most of the esters. Spray-dried particles were all spherical, whereas lyophilized particles were irregularly shaped. The particle size ranged from 6.28 μm to 12.15 μm for spray-dried powders and from 14.19 μm to 50.97 μm for lyophilized powders. The findings indicate that both encapsulation methods are effective for the preparation of craft beer powder. However, freeze-drying can encapsulate the bioactive and volatile compounds in craft beer more effectively than spray-drying and aid in the better retention of craft beer characteristics.
研究领域:
食品科学
·
化学工程
·
分析化学
✓ 已验证
产品关联
DOI
高影响因子
ACS Biomaterials Science & Engineering
·
2023
·
IF 5.8
Jinni Luo,Huanxia Wang,Jinfei Wang,Yuan Chen,Chenglong Li,Kejun Zhong,Jie Xiang,Pengxiang Jia
Conductive hydrogels have been in huge demand in biomedical and wearable electronics. However, the application of traditional conductive hydrogels is largely limited due to their poor mechanical properties. Here, a conductive hydrogel with excellent mechanical strength and swelling resistance properties is prepared by ion cross-linking, directional freeze-drying, and rehydration. First, the acrylamide and acrylic acid are polymerized in the κ-carrageenan solution to form the hydrogel. Then, the obtained hydrogel is cross-linked with Fe3+ by soaking in ferric chloride solution. Finally, the ionic cross-linked hydrogels are reinforced by directional freeze-drying and rehydration. The resulting hydrogel has excellent tensile strength (5.67 MPa) and high toughness (7.63 MJ/m3). It is worth noting that the hydrogel also had excellent anti-swelling properties. Its mechanical strength and volume almost show no changes after soaking in deionized water for 40 days. In addition, the hydrogel exhibits good ionic conductivity (0.091 S/m), high sensitivity, and excellent stability when applied as a strain sensor. This work proposes a simple method to fabricate a conductive hydrogel with great mechanical properties and swelling resistance, which displays huge potential in varied fields.
研究领域:
生物医学工程
·
材料科学
·
可穿戴设备
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Science of Advanced Materials
·
2021
·Vol. 13
·期 9
·1820-1824
·
IF 1.474
Huo Jian-Chun,Yang Hai-Xia,Ma Yuan,Bai Jie
Natural cotton fiber used for reinforcement is low-cost, environmentally friendly, good flexibility and easy to obtain. In this study, a new cotton fiber/silica aerogel composite was developed by sol–gel method via freezedrying. The obtained composite has excellent flexibility
and can be restored to its original state after bending for 180° without obvious cracks. After 20 cycles continuous compression, the total unrecoverable strain loss is only 20% under strain of 60%. The composite also shows very prominent hydrophobicity, and the contact angle with water
reaches 145 degrees. It has strong adsorption capacity for organic reagents and oil, with adsorption ratios of 500% and 600%, respectively. In addition, the composite has a low thermal conductivity of 0.038 W/(m·K) at room temperature. The obtained composite exhibits considerable promise
in oil-water separation and thermal insulation.
研究领域:
材料科学
·
环境科学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）