FOOD HYDROCOLLOIDS
·
2018
·
IF 5.089
Ziyu Deng,Fang Wang,Bin Zhou,Jing Li,Bin Li,Hongshan Liang
In this study, polygalacturonase (PG) was immobilized in calcium alginate microspheres prepared using endogenous emulsification method and its application in apple juice clarification was evaluated. Preparation conditions of calcium alginate microspheres prepared by endogenous emulsification were optimized, additionally, the formed microspheres were characterized. Under optimal conditions, microspheres with the particle size of 38.0 ± 0.2 μm showed good sphericity, storage stability and a narrow particle size distribution. Meanwhile, single factor experiment and response surface experiment were combined to get the optimum conditions of immobilizing PG. The immobilized enzyme presented the optimum temperature at 60.0 °C, which was almost 10.0 °C higher than the free PG and the activity was less dependent upon pH within the interval of 3.0–4.5 than free enzyme, supporting the immobilized enzyme more stable in apple juice clarification (pH = 4.3 ± 0.1). The immobilized enzyme also exhibited good operational stability and 63.0% of its initial activity retained after three batch reactions. In the present of the immobilized PG, the turbidity of apple juice decreased, as well as apple juice had good thermal and freezing ability.
研究领域:
食品科学
·
生物技术
✓ 已验证
产品关联
DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2020
·
IF 5.774
Xiao-lei Wang,Wei Qin,Li-xin Wang,Kong-yin Zhao,Hui-cai Wang,Hong-yu Liu,Jun-fu Wei
In order to recover dyes from textile wastewater, a self-supported carboxylated titanium dioxide/calcium alginate (TiO 2 -COOH/CaAlg) hydrogel nanofiltration membrane was prepared using TiO 2 -COOH as the reinforcing agent. The Scanning electron microscopy (SEM) and Energy dispersive X-ray (EDX) mapping scanning spectra were employed to characterize the distribution of TiO 2 -COOH nanoparticles on the membrane surface. The pore size distribution, zeta potential and mechanical performance of the membrane were evaluated. The rejections for single dye solutions, salt solutions and dye/salt mixture solutions were also examined. The results indicate that the TiO 2 -COOH nanoparticles are dispersed uniformly on the membrane surface. Compared to CaAlg membrane, the tensile strength of 20 wt% TiO 2 -COOH/CaAlg membrane is enhanced by 328%. At the operating pressure of 0.1 MPa, the rejection ratios of 20 wt% TiO 2 -COOH/CaAlg membrane for 100 mg/L Brilliant blue G250, Direct black 38 and Congo red are 98.4%, 96.8% and 95.9% respectively, and the permeate flux is about 14.1 L·m −2 ·h −1 . Meanwhile, this membrane possesses the low rejection ratios for inorganic salts (16.1%, 15.6%, 12.3% and 9.0% for MgSO 4 , Na 2 SO 4 , MgCl 2 and NaCl, respectively), excellent dye anti-fouling property and good stability in the long-term filtration for dye/salt mixture solution.
研究领域:
材料科学
·
环境工程
✓ 已验证
DOI
高影响因子
Environmental Technology & Innovation
·
2023
·
IF 7.1
Yining Ji,Na Zheng,Bo Wu,Qirui An,Zimeng Li,Siyu Sun,Wenhui Zhang,Xiaoqian Li,Sujing Wang
A novel adsorbent was synthesized for the capture of heavy metals mixture in water by encapsulating hydroxyapatite-modified wood ear mushroom sticks biochar in calcium alginate beads (CA-HAP MB ). The surface structure and adsorption mechanism of the CA-HAP MB were characterized by Scanning electron microscopy and X-ray energy dispersion spectroscopy (SEM-EDS), Fourier transform infrared spectrometer (FTIR), X-ray diffraction patterns (XRD), and X-ray photoelectron spectroscopy (XPS). Under different conditions, CA-HAP MB for Cd 2 + and Pb 2 + were investigated for their adsorption properties in water and their competition. The adsorption capacities of Cd 2 + and Pb 2 + on the aerogel spheres reached 302.2 mg g −1 (2.69 mmol g −1 ) and 564.5 mg g −1 (2.73 mmol g −1 ), respectively (based on Langmuir). The aerogel spheres are easier to collect than biochar materials. The results show that CA-HAP MB composite aerogel spheres have a good application prospect in capturing heavy metal ions from water.
研究领域:
环境科学
·
材料科学
✓ 已验证
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2024
·
IF 13.3
Lu He,Gege Bao,Xi Yu,Xiaofeng Zhang,Xiaobei Jin,Zixuan Yu,Ying He,Rong Zhang,Daochun Qin
Developing environmentally friendly methods for modifying bamboo is important. This study proposed a method to enhance the flame retardancy of bamboo through calcium alginate (CaAlg) forming and hydroxyapatite (HAP) mineralization. Scanning electron microscopy and elemental analysis demonstrated that HAP was uniformly deposited within and on the surface of bamboo cells with the assistance of CaAlg. The residue yield of the treated bamboo increased by 49.8% and 40.7% under air and nitrogen atmospheres, respectively. The limiting oxygen index increased from 23.4% to 26.6%. Furthermore, compared to the untreated bamboo, the treated bamboo exhibited reductions of 45.2%, 25.8%, 25.6%, and 30.7% in peak heat release rate, total heat release, peak smoke production, and total smoke release, respectively. The layer of CaAlg and HAP particles cross-link within the bamboo cells, forming a dense protective barrier that prevented the entry of heat, flammable gases, and the release of toxic smoke. The mechanical properties of the bamboo were not reduced by this gentle treatment. The mineralized bamboo fabricated using this method showed potential as a sustainable building material due to its improved flame retardancy and mechanical properties.
研究领域:
材料科学
·
生物质工程
✓ 已验证
产品关联
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2019
·
IF 3.375
Yongcun Song,Nan Wang,Li-ye Yang,Yang−guang Wang,Di Yu,Xiao-kun Ouyang
Metal–organic frameworks (MOFs) have received special attention from scientists owing to their excellent adsorption performance. However, the difficulty in separating MOFs from adsorbed metals following use has limited their application. A zeolitic imidazole-based MOF with broad applicability for sorption of Pb(II) is examined. In this work, a novel adsorbent employing ZIF-8/calcium alginate microparticles was prepared using sodium alginate and ZIF-8. This adsorbent was characterized using scanning electron microscopy, Fourier-transform infrared spectroscopy, X-ray diffraction analysis, and X-ray photoelectron spectroscopy. The performance of the ZIF-8@CA microparticles in adsorbing Pb(II) from a Pb(II) solution was investigated, and the impacts of the initial Pb(II) concentration, reaction time, pH, and reaction temperature on the reaction process were investigated. The results showed that ZIF-8@CA microparticles exhibited a maximum adsorption capacity of 1321.21 mg/g at pH 5 after 120 min, and the adsorption process was found to fit the Langmuir isotherm model (R2 = 0.9856) and the pseudo-second-order kinetic model (R2 = 0.9999). These results showed that the adsorption of Pb(II) was an endothermic process. The regeneration experiment with ZIF-8@CA revealed that the removal efficiency of Pb(II) was greater than 80% even after five cycles.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
FOOD CHEMISTRY
·
2024
·
IF 8.5
Yumeng Shi,Jiayi Tang,Wenyu Yan,Yan Liu,Yuchun Liu,Huan Chen,Cheng Yang,Chunhuan Liu,Rong Liang
Oleogels have been explored as a new lipid-based delivery system, however, their insolubility and unsuitable shape severely limit their application in food systems. Herein, core-shell oleogel capsules with high monodispersity (coefficient variation (CV) < 5%)) were prepared via gravity-assisted co-flowing microfluidic device and simply air-drying. The oleogel capsules with oleogel core and ultrathin calcium-alginate shell were prepared. Oleogel capsules maintained their original shape at pH = 2.0 but swelled rapidly at pH = 6.8 and 7.4. The swelling ratio of shell can be adjusted by inner fluid flow rate ( Q in ). Notably, the core with beeswax (BW) crystal network, effectively improved the stability performances and also could provide thermal response. Finally, the oleogel capsules demonstrated excellent sustained release and UV protection of lipophilic bioactives. This work sheds light on development of novel oleogel capsules, making them ideal candidates for smart food encapsulation applications.
研究领域:
食品科学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
·
2021
·
IF 7.312
Yue Zhang,Kongyin Zhao,Zhenhao Yang,Zhijian Zhang,Zhilong Guo,Rongrong Chu,Wei Zhang,Wenxiong Shi,Jiacheng Li,Ziyi Li,Haiyi Liu,Anhou Xu,Xi Chen
Calcium alginate (CaAlg) hydrogel has good anti-pollution performance. However, the self-supporting CaAlg hydrogel filtration membrane is difficult to be batch prepared due to its poor mechanical properties. In this paper, polyester (PET) non-woven fabric, polypropylene (PP) non-woven fabric and polyhydroxybutyrate (PHB) nanofibers were used as support layer to prepare CaAlg composite membranes. A series of studies proved that CaAlg-PET membrane showed higher stability and flux, which revealed that PET non-woven fabric was the best carrier among the three fiber carriers to enhance the various properties of hydrogel. Methyl blue (MB) and sodium chloride (NaCl) were used as the representatives of molecules and ions, respectively. The effects of concentration, operating pressure and temperature on the separation performance of MB/NaCl by CaAlg-PET membrane were investigated. The flux of CaAlg-PET membrane was 19.3 L·m −2 ·h −1 ·bar −1 , and the membrane showed a high selectivity of 183.4 to MB/NaCl mixture (99.5% rejection of MB and 8.3% rejection of NaCl). Moreover, Barium ion was used to cross-link sodium alginate to prepare barium alginate (BaAlg) hydrogel coated composite membrane (BaAlg-PET) using PET fiber as the carrier. The BaAlg-PET membrane exhibited higher strength, stability, flux and better separation performance than CaAlg-PET membrane. BaAlg-PET membrane exhibited a high flux of above 35.5 L·m −2 ·h −1 ·bar −1 , and the molecular ion selectivity was 306.3 (99.7% rejection of MB and 8.1% rejection of NaCl). Membrane pore structure and pore size distribution of BaAlg hydrogel membrane were generated by molecular dynamic (MD) simulations. In sum, this work provided a green, economical and expandable new idea and membrane material for the separation of molecules and ions.
研究领域:
材料科学
·
环境科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY
·
2017
·
IF 3.743
Xiaofeng Yi,Jiarui He,Yingyuan Guo,Zhenhua Han,Meixia Yang,Jiali Jin,Junjie Gu,Minrui Ou,Xiaoping Xu
The aim of this work was to study the removal of Cu (II) and U (VI) ions from aqueous solutions by encapsulating magnetic Fe 3 O 4 nanoparticles into calcium alginate coated chitosan hydrochloride (CCM) hydrogel beads. ATR-FTIR and XRD analysis data indicated that the CCM composites were successfully prepared. SEM images and EDX spectra showed that Cu 2+ and UO 2 2+ ions were adhered onto sorbents . Adsorption properties for removal of both copper and uranium ions under various experimental conditions were investigated. Kinetic data and sorption equilibrium isotherms were also conducted in batch process . The sorption kinetic analysis revealed that sorption of Cu (II) and U (VI) followed the pseudo-second-order model well and exhibited 3-stage intraparticle diffusion model during the whole sorption process. Equilibrium data were best described by Langmuir model, and the CCM composite hydrogel beads showed the estimated maximum adsorption capacity 143.276 mg/g and 392.692 mg/g for Cu (II) and U (VI), respectively. The CCM adsorbent exhibited excellent reusability for five cycles use without significant changes in the adsorption capacity and structural stability. The results demonstrated that CCM can be an effective and promising sorbent for Cu (II) and U (VI) ions in wastewater.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Applied Nano Materials
·
2024
·
IF 5.3
Haitao Zhang,Jiajie Cai,Jieying Su,Meiting Zhu,Yuanyuan Gong,Bin Xu
A synthesis strategy of calcium alginate/silver nanosheet microencapsulated phase change material (Alg/Ag-MEPCM) with controlled morphology was proposed, which is assisted with calcium carbonate microencapsulated phase change material (CaCO3-MEPCM) as a template. After successively adsorbing alginate and Ag+ on the template surface, the addition of l-ascorbic acid dissolved CaCO3 in the template to synthesize calcium alginate, while Ag+ was reduced to silver nanosheets by controlling the concentrations of the alginate and Ag+. The Alg/Ag-MEPCM exhibited a satisfactory latent heat storage capacity of 99.51 J/g, which enabled the PVA hydrogels containing Alg/Ag-MEPCM to have favorable temperature regulation ability. Moreover, the abundant silver nanosheets in Alg/Ag-MEPCM provided the PVA hydrogel containing Alg/Ag-MEPCM with a favorable antimicrobial capacity. Thus, the Alg/Ag-MEPCM prepared in this work has a promising application in the fields of thermal energy storage, thermoregulation, and antimicrobials, specifically as wound dressings and food packaging.
研究领域:
材料科学
·
生物医学工程
·
热能存储
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF SOL-GEL SCIENCE AND TECHNOLOGY
·
2019
·Vol. 91
·期 2
·353-363
·
IF 1.986
Sun Xiaoxiao,Hu Dalin,Yang Li–Ye,Wang Nan,Wang Yang-Guang,Ouyang Xiao–kun
Abstract As a typical metal–organic framework material, UiO-66 has good potential for removing pharmaceuticals and personal care products from water. However, the application of this powdery adsorbent has been limited by the difficult recovery from the liquid. To overcome this weakness, we prepared composite beads constituted by sodium alginate and UiO-66 by solidification in CaCl 2 solution. The material was characterized by SEM, FTIR, XRD, BET, and TGA methods. These composite beads were applied to remove a common antibiotic Levofloxacin (LOFX) from water, and the experimental parameters (i.e., initial LOFX concentration, adsorption time, pH, and adsorbent dose) were optimized. The adsorption data could be satisfactorily fitted to the Langmuir isotherm model ( R 2 = 0.9871) and the pseudo-second-order kinetic model ( R 2 = 0.9990). The regeneration experiment of the composite beads revealed that the adsorption efficiency of levofloxacin was higher than 70% even after 5 cycles.
Scheme 1 Synthesis route of UiO-66/CA
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
CELLULOSE
·
2021
·Vol. 28
·期 13
·8751-8769
·
IF 5.044
Liu Jinru,Yu Zhicai,He Hualing,Wang Yushu,Zhao Yuhang
Abstract Design and development of fire-resistant composite materials with improved flame retardancy are critically needed for firefighters in fire protection fields. Herein, a novel fire-resistant composite hydrogel (FRCH) was fabricated based on calcium alginate (CA), poly (vinyl alcohol) (PVA) and expandable graphite (EG). The obtained FRCH material displayed prominent flame retardancy due to a large amount of heat was removed as contained water evaporation. Meanwhile, the EG in hydrogel occurred expansion to prevent heat transfer when exposed to fire. Results indicated that peak heat release rate and total release rate of FRCH decreased from 264.9 to 67.2 W/g and 15.4 to 12.1 KJ/g, respectively. The thermal kinetic behavior of FRCH was investigated by using Flynn-Wall-Ozawa (FWO) and Kissinger-Akahira-Sunose (KAS) models. TPP test further confirmed that introduction of EG in hydrogel prolonged the second-degree skin burn time for 2.73 s compared to without EG component. Besides, benefiting from the expansion behavior of EG when being burned, EG formed a conductive pathway and resulting in LED light up. This work provided an effective way to prepare flame retardant composite material with an early fire warning detection function, which may meet the requirements in firefighting fields. Graphic abstract
研究领域:
材料科学
·
燃烧学
·
复合材料工程
✓ 已验证
产品关联
DOI
高影响因子
Journal of Environmental Chemical Engineering
·
2022
·
IF 7.968
Fei Yu,Junyao Pan,Yiyao Li,Yidi Yang,Zhi Zhang,Jiayang Nie,Jie Ma
Due to the high dependence on tetracycline in the daily production and life of human beings, its abuse problem is serious, which affects the safety of the ecological environment. How to effectively remove residual tetracycline in the environment is an urgent problem to be solved. In this study, HKUST-1 was successfully composited with rice husk and wheat straw biochar by hydrothermal method, and then combined with κ-carrageenan and calcium alginate by cross-linking replacement method to prepare a novel modified biochar composite gel. Through a series of static adsorption experiments, the adsorption of TC on the two modified biochar composite gels reached equilibrium within 24 h and was dominated by chemical adsorption , and the maximum adsorption capacities for TC could reach 313.00 and 396.09 mg·g −1 , respectively. The adsorption mechanism of TC on the modified biochar composite gels is mainly hydrogen bonding, electrostatic attraction, metal-organic complexation and π-π interaction. At the same time, the dynamic adsorption process was simulated through a fixed-bed column experiment, and the results showed that the modified biochar composite gels as a new type of adsorption material can be effectively applied to the removal of organic pollutants in actual sewage, providing basic support for future practical application research.
研究领域:
环境科学
·
材料科学
✓ 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）