CARBOHYDRATE POLYMERS
·
2022
·
IF 10.723
Haoyue Ning,Lixin Lu,Jing Xu,Lijing Lu,Liao Pan,Zidong Lin
The purpose of this study was to compare the effects of different concentrations of the amine-functionalized isoreticular metal-organic framework-3 loaded with carvacrol (IRMOF-3/CA) on the properties of sodium alginate (SA) composite films, thus determining the optimal addition amount and further preparing bioactive packaging film with antibacterial and antioxidant activities. The morphology, structure, physical properties, antioxidant and antibacterial activities of the films were characterized and analyzed. The results showed that the thermal stability and light barrier property of the films were improved by the addition of IRMOF-3/CA. When the additional concentration was 0.4 wt%, the tensile, water vapor barrier and hydrophobic properties of the films were increased by 30.13%, 9.06% and 46.43% respectively compared with those of pure SA film. Moreover, the film added with IRMOF-3/CA had sustained antioxidant and antibacterial activities , and had an apparent fresh-keeping effect on pork, suggesting its application potential in food packaging.
研究领域:
食品科学
·
材料科学
·
生物化学
✓ 已验证
DOI
高影响因子
EUROPEAN JOURNAL OF PHARMACOLOGY
·
2016
·
IF 2.73
Ming Zong,Dan-Dan Fan,Shan Lin,Yan-Ping Song,Ze-Yu Wang,Xiao-Liang Ma,Wei-Hua Qiu,Yu-Hua Bai,Lei Li,Sen Li
Aspirin has been used in the treatment and chemoprevention of many malignant cancers. The mechanism of its anti-cancer activity mainly involves the inhibition of cyclooxygenase-2 (COX-2). However, the application of aspirin is limited by the serious gastric mucosal damage that accompanies its usage. We have previously reported the preparation of a novel aspirin derivative that we named Ca-Asp, and showed that it causes less damage to gastric mucosa of rat and inhibits the expression of COX-2 to higher degree than Asp. However, the anti-cancer effect and mechanism of Ca-Asp was not demonstrated. In this study, the anti-cancer effect of Ca-Asp was investigated and compared with those of Asp and Hydroxyapatite (Hap) at the cell level. The results showed that treatment of SGC-7901 cells (human gastric cancer cell line) with 200–400 μg/ml Ca-Asp resulted in significant reduction in cell viability , compared to treatment with either Asp or Hap, and at a higher concentration (500 μg/ml). Subsequent investigation into the possible underlying mechanism showed that Ca-Asp induced apoptosis and caused cell cycle arrest at the G1 phase . Ca-Asp also up-regulated the levels of caspase-3 and p53, but down regulated the level of cyclin D1 , NF-κB, COX-2 and PGE 2 . Furthermore, simultaneous treatment of SGC-7901 cells with Ca-Asp and exogenous PGE 2 reduced the anti-proliferative effect of Ca-Asp on the cells. Taken together, the results suggested that Ca-Asp might act as a potential anti-cancer drug, and that its suppression of PGE 2 production might constitute an important part of its anti-cancer activity.
研究领域:
肿瘤学
·
药理学
·
分子生物学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
INORGANIC CHEMISTRY
·
2023
·
IF 4.6
Man Tian,Qin Cao,Huina Wei,Keke Hou,Xiaoxu Duan,Wenzhuo Chen,Jungu Xu
Developing oxide ion conductors with new structural families is important for many energy conversion and storage techniques. Herein, a series of Ca-doped Yb3Ga5O12 garnet-type materials are prepared through a traditional solid-state reaction method, with their oxide ion conduction properties being reported for the first time. The results revealed that Ca substitution for Yb would significantly improve the conductivity of Yb3Ga5O12 from 3.57 × 10–7 S/cm at 900 °C under air to 1.66 × 10–4 S/cm, with an oxide ion transporting number of ∼0.52. The oxygen vacancy defect formation energy (∼0.127 eV) and the local structure around an oxygen vacancy were studied by atomic-level static lattice simulations based on the interatomic potential method. The oxide ion conducting mechanism was studied by the bond-valence-based method, which revealed three-dimensional pathways for oxide ion migration in both the parent and Ca-doped structures. The simulated activation energy of oxide ion migration decreased slightly from ∼0.358 eV in the parent structure to 0.346 eV in the doped one. These discoveries in the Ca-doped Yb3Ga5O12 will stimulate extensive exploitation and fundamental research on garnet-type materials.
研究领域:
材料科学
·
固体离子学
·
能源材料
·
计算材料科学
✓ 已验证
DOI
高影响因子
MATERIALS SCIENCE FORUM
·
2021
·
IF 0
Sha Chen,Jing Hua Gong,Jing Hong Ma
Helix is a sophisticated structure in nature and has many unique functions which makes it possible to store more information and energy, even receive more sensitive signals. Besides, as an effective method for preparing hydrogel fibers, microfluidic spinning has achieved unprecedented development in the past decade. However, hydrogel fiber with helical structure has began to be studied only in recent years. In this paper, the helical hydrogel fibers were prepared by the microfluidic spinning method. The microfluidic chip was assembled by PDMS connector, collection tube, inner and outer channels. Sodium alginate (SA) and calcium chloride were used as the core fluid and sheath fluid, respectively. By designing and adjusting the length of the chip, changing the concentration of SA and the ratio of two flow rates (inner flow rate/outer flow rate), a continuous and uniform helical hydrogel fiber was prepared. The relationships between the diameter of the fiber, the pitch of the helix and the concentration of SA, the ratio of two flow rates were discussed. The results showed that the diameter of the fiber was mainly affected by the core fluid. Within a certain range, as the concentration of SA increased, the diameter of the fiber increased. Besides, the pitch of the helix was greatly affected by the flow rate of sheath fluid. As the velocity of the sheath fluid increased, the pitch of the fiber increased. Such helical fiber could be used in micro sensors when added some conductive materials or crosslinked with some temperature responsive polymers such as N-isopropylacrylamide.
研究领域:
材料科学
·
生物医学工程
✓ 已验证
DOI
JOURNAL OF CATALYSIS
·
2016
·
IF 7.354
Fangfang Wu,Gang Liu,Xiaoxiang Xu
LaTiO 2 N has been considered a promising candidate for efficient photocatalytic water splitting. However, its photocatalytic activity is often hampered by the presence of structural defects and poor charge mobility. In this work, we introduced Ca into the crystal structure of LaTiO 2 N via a simple co-precipitation method and investigated the photocatalytic and photoelectrochemical properties for the full range solid solution La 1− x Ca x TiO 2+ y N 1−y (0 ⩽ x , y ⩽ 1). Our results show that incorporating Ca into LaTiO 2 N induces a strong structural shrinkage as well as a space group change from I mma to P nma around a middle doping point ( x = 0.5). The presence of Ca effectively boosts the photocatalytic oxygen production and aids photocurrent extraction for LaTiO 2 N. The best photocatalytic activity was achieved for sample La 0.3 Ca 0.7 TiO 2.7 N 0.3 with oxygen production rate ∼66.96 μmol/h under visible light illumination ( λ ⩾ 420 nm), corresponding to apparent quantum efficiency ∼3.13%. XPS analysis revealed a substantial reduction in surface Ti 3+ species and a removal of A-site cation segregation for samples containing Ca. Further photoelectrochemical analysis highlights the critical role of Ca in enhancing the charge mobility of LaTiO 2 N. The better photocatalytic performance of Ca-modified LaTiO 2 N can be understood as a result of defect removal, high charge mobility, and improved surface charge migration pathways that considerably prolong the lifetimes of photogenerated charges.
研究领域:
材料科学
·
化学工程
·
能源科学
✓ 已验证
产品关联
DOI
高影响因子
Frontiers in Bioengineering and Biotechnology
·
2020
·
IF 3.644
Shao Fei,Yu Lei,Zhang Yang,An Chuanfeng,Zhang Haoyue,Zhang Yujie,Xiong Yi,Wang Huanan
Microfluidics-based alginate microgels have shown great potential to encapsulate cells in a high-throughput and controllable manner. However, cell viability and biological functions are substantially compromised due to the harsh conditions for gelation, which remains a major challenge for cell encapsulation. Herein, we presented an efficient and biocompatible method by on-chip triggered gelation to generate microfluidic alginate microgels for single-cell encapsulation. Two calcium complexes of calcium–ethylenediaminetetraacetic acid (Ca-EDTA) and calcium–nitrilotriacetic (Ca-NTA) as crosslinkers for triggered gelation of alginate were compared and investigated for feasible application. By triggered release of Ca2+ ions from the calcium complex via adding acetic acid in the oil phase, the alginate precursor in the aqueous droplets can be crosslinked to form alginate microgels. Although using Ca-EDTA and Ca-NTA both achieved on-chip gelation, Ca-NTA led to significantly higher cell viability since the dissociation of Ca2+ ions from Ca-NTA can be obtained using less concentration of acid compared to Ca-EDTA. We further demonstrated the functionality of encapsulated mesenchymal stem cells (MSCs) in alginate microgels prepared using Ca-NTA, as evidenced by the osteogenesis of encapsulated MSCs upon inductive culture. In summary, our study provided a biocompatible strategy to prepare alginate microgels for single-cell encapsulation which can be further used for applications in tissue engineering and cell therapies.
研究领域:
生物技术
·
组织工程
·
细胞生物学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Building Engineering
·
2024
·
IF 6.7
Baomin Wang,Weigao Ding,Chengcheng Fan,Fei Liu,Wenxin Lu,Haoxiang Yang
C-S-H gel is a complex cementitious system, and the properties present significant difference with various Ca/Si ratios. The immobilization mechanism of three heavy metals in C-S-H gel at various Ca/Si ratios was investigated in this work from the prospect of the physical adsorption and chemical immobilization. Results showed that higher Ca/Si ratios can result in an increase in silicon chain polymerization, and lower BET specific area, and C-S-H gel with various Ca/Si ratios showed the excellent immobilization for heavy metals. Pb(II) and Zn(II) can form hydroxyl complex polyhedra in C-S-H under strongly alkaline environments, and increase the silicon chain polymerization degree similar to the doping of C-S-H gel by Al. However, Cd(II) was immobilized in the C-S-H gel with the formation of a solid solution under the action of ion exchange with Ca(II), rather than in the form of hydroxyl complex polyhedral and cadmium hydroxide coprecipitates. The highest adsorption capacity of Pb(II) was realized in C-S-H gel with a Ca/Si molar ratio of 0.9, reaching 95.6006 mg/g. Pb(II) was mainly immobilized in C-S-H gel via physical and chemical adsorption, and the effect of chemical adsorption tended to be significant as the Ca/Si molar ratio increased. And the formation of Pb 8 Ca(Si 2 O 7 ) 3 can be detected in C-S-H gel with a higher Ca/Si molar ratio.
研究领域:
材料科学
·
环境科学
✓ 已验证
DOI
高影响因子
JOURNAL OF THE ENERGY INSTITUTE
·
2021
·
IF 6.186
Youjian Zhu,Yun Liu,Liang Wang,Wei Yang,Haiping Yang,Long Jiang,Zhenyi Du,Jingai Shao,Hanping Chen
Combustion of agricultural residues for heat and electricity production is an efficient way to reduce amount of such waste source and emissions due to inappropriate treatment of them. However, unlike other biomass materials, agricultural residues often have high content of ash and certain ash forming elements with low meting temperatures, resulting in sintering and slagging during combustion processes . It complicates combustion of agricultural residues and restricts further utilization of this renewable energy source . In this work, sintering of a typical agricultural biomass cornstalk and effect of two phosphate additives, Ca(H 2 PO 4 ) 2 ·H 2 O and NH 4 H 2 PO 4 , were investigated by a combination of various techniques. Results indicated that the addition of Ca(H 2 PO 4 ) 2 ·H 2 O increased the initial melting temperature of cornstalk ash by 64–209 °C. The ash sintering behavior was greatly improved as a result of formation of high melting temperature K–Ca phosphates, Ca 9 MgK(PO 4 ) 7 and Ca 2 KP 3 O 10 upon addition of the Ca(H 2 PO 4 ) 2 ·H 2 O. It is accompanied with reduced generation of low melting temperature K-rich silicates and the formation of large ash aggregates. Addition of NH 4 H 2 PO 4 increased the initial ash melting temperature by 28–116 °C, but it had slight influence on the cornstalk ash sintering characteristics. The analysis revealed that, although the addition of NH 4 H 2 PO 4 resulted in the formation of high melting temperature K 2 CaP 2 O 7 , certain amount of K phosphates and silicates eutectics were still formed, initiating and promoting sintering of ash from mixture of cornstalk and NH 4 H 2 PO 4 . Reactions between Ca(H 2 PO 4 ) 2 ·H 2 O and potassium salts under different conditions were also studied. It was found that reactions between Ca(H 2 PO 4 ) 2 ·H 2 O and potassium salts might already start as the temperature higher than 300 °C. K 2 CaP 2 O 7 , Ca 2 P 2 O 7 , Ca(PO 3 ) 2 and KCa(PO 3 ) 3 were identified as main products from these reactions and amounts of them considerably depends on the heat treatment temperatures and mixing ratios between Ca(H 2 PO 4 ) 2 ·H 2 O and potassium salts. Compared to KCl, K 2 CO 3 had a higher reactivity toward the Ca(H 2 PO 4 ) 2 ·H 2 O under same study conditions. The current work shows the addition of Ca(H 2 PO 4 ) 2 ·H 2 O is a promising approach to alleviate the ash sintering issues and assure efficient and smooth combustion of cornstalk.
研究领域:
能源与环境科学
·
生物质能研究
✓ 已验证
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2025
·
IF 6.3
Yongjun Wei,Feiping Lu,Xinqi Ai,Ju Lei,Yong Bai,Ziang Wei,Ziyin Chen
During the solution-based fabrication of perovskite solar cells (PSCs), the rapid and uncontrollable process of crystal nucleation and growth leads to the formation of numerous defects at the surface and grain boundaries, resulting in severe non-radiative recombination, which negatively affects the optoelectronic performance of the device. In this work, two passivation molecules, 2-(3-Pyridyl)-1H-benzimidazole (PBI) and 2-(3-Pyridyl)-1H-benzimidazole-6-carboxylic acid (PBI-CA), were introduced onto the surface of the perovskite film via a post-treatment method. PBI contains two basic functional groups, -C-N and -C N, where the nitrogen atom possesses a lone electron pair. PBI-CA has the same functional groups but also includes a carboxylic acid (-COOH) functional group, which contains both a carbonyl and a hydroxyl group, also having non-bonding electron pairs. The lone electron pairs in these functional groups exhibit Lewis base characteristics, which can coordinate with the uncoordinated Pb 2 + ions in the perovskite film, thereby passivating the ion defects caused by Pb 2+ . Compared to PBI alone, PBI-CA has an additional carboxylic acid group, providing more Lewis base sites, making it more effective in coordinating with Pb 2+ and passivating defects. We investigated the passivation mechanism of these two passivators through first-principles calculations and demonstrated their positive impact on PSCs through experiments and characterizations. The introduction of PBI and PBI-CA increased the size of the perovskite crystals, improved the power conversion efficiency (PCE), and enhanced device stability. The results showed that in a perovskite system with a bandgap of 1.6 eV, the PCE of the PBI-CA-modified device reached 21 %, higher than that of the PBI-modified device (20.3 %) and the baseline device (18.6 %), with significantly improved device stability. These Lewis base-containing molecules can be widely used to fabricate high-performance PSC devices.
研究领域:
材料科学
·
能源科学
✓ 已验证
产品关联
DOI
高影响因子
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
·
2023
·Vol. 25
·期 35
·23761-23769
·
IF 3.3
Juanqin Xue,Peng Wang,Wen Cheng,Long Shi,Qiang Bi
TiO2/BiOI/CA electrodes with improved conductivity, reduced photoelectron–hole recombination rates, and increased reaction sites based on p–n type heterojunctions were constructed on carbon aerogels (CA) as photoelectrode substrates. Characterization based on ultraviolet-visible diffuse reflectance spectroscopy, photocurrent measurements, and impedance analysis showed that the TiO2/BiOI/CA photoelectrode with a Ti/Bi mole ratio of 0.4 exhibited the best visible light absorption, lowest photogenerated electron–hole pair recombination rate, and strongest photocatalytic degradation, with 90.4% degradation of phenol under 120 min of light. Moreover, the stability of this electrode remained at a high level. This was mainly because the energy levels of TiO2 and BiOI matched each other and the p–n heterojunction formed adjusted the energy band structure of the composite material, widened the electron transfer path, formed an internal electric field between the phase interfaces, had a higher electron transfer rate, and reduced the photogenerated electron–hole recombination rate. Since ˙OH and ˙O2− are the main active substances in the degradation of phenol, the TiO2/BiOI/CA photoelectrodes had higher degradation efficiency than BiOI/CA electrodes. This study provides a unique concept for the treatment of organic pollutant wastewater and electrode design for photoelectrocatalysis.
研究领域:
材料科学
·
环境科学
·
光催化
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CERAMICS INTERNATIONAL
·
2021
·Vol. 47
·期 24
·34568-34574
·
IF 4.527
Wenlong Huang,Ying Li,Haiqiang Lu,Yushi Ding,Yandong Liu
Doped CaZrO 3 proton conductors are promising materials for electrochemical hydrogen sensors, which have already been used in commercialized hydrogen sensors for aluminum melts. Hafnium and Zirconium possess similar properties but their influences on conductive properties of CaZrO 3 proton conductors have not been well investigated. In this study, CaZr 0.9 Sc 0.1 O 2.95 and CaHf 0.9 Sc 0.1 O 2.95 were prepared by solid-state reaction, and their conductivities and transport properties were systematically investigated by defect equilibria model. Total conductivities of CaZr 0.9 Sc 0.1 O 2.95 and CaHf 0.9 Sc 0.1 O 2.95 reached 4.70 × 10 −5 −1.69 × 10 −3 S·cm −1 and 4.83 × 10 −6 −9.71 × 10 −4 S·cm −1 under humid air and 400 °C−800 °C. Their total standard molar hydration enthalpies were estimated to −59.1 kJ/mol and −56.9 kJ/mol, respectively. Conductivities of grain interiors were higher than those of total conductivities, and activation energies of protons were lower than oxide vacancies and holes. Transport numbers showed protonic conduction of Ca(Zr/Hf) 0.9 Sc 0.1 O 2.95 to always dominate under humid air at 400 °C−700 °C. Protonic transport numbers of CaZr 0.9 Sc 0.1 O 2.95 and CaHf 0.9 Sc 0.1 O 2.95 were estimated to 0.41 and 0.44 at 800 °C, respectively. Meanwhile, protonic transport number of grain interiors was higher than that of total sample. Therefore, grain interior could block the transfer of oxide vacancies and holes. In sum, these findings look promising for application on electrochemical hydrogen sensors.
研究领域:
材料科学
·
电化学
·
固体离子学
·
传感器技术
✓ 已验证
DOI
高影响因子
FOOD CHEMISTRY
·
2022
·
IF 9.231
Kai Si,Tingting Gong,Suyun Ding,Huiping Liu,Shuyuan Shi,Jianqiu Tu,Linxian Zhu,Li Song,Lushan Song,Xiaowei Zhang
Phosvitin has excellent calcium binding capacity, related to its phosphopeptides. The phosphopeptides may be used as functional ingredients for improving calcium bioavailability, but the calcium-binding mechanism is unclear. In this study, a novel phosvitin phosphorylated pentapeptide (Glu-Asp-Asp-pSer-pSer, EDDpSpS) was selected to prepare an EDDpSpS calcium complex (EDDpSpS-Ca), and the calcium-binding mechanism and bioavailability investigated. The calcium-binding capacity of EDDpSpS was up to 468 ± 152.80 mg/g. Calcium ions prompted the folding of the EDDpSpS structure to form spherical nanoparticles. The calcium binding sites of EDDpSpS involved peptide bonds, carboxyl, amino, and phosphate groups. Molecular forces involved in these interactions were electrostatic in nature. Moreover, EDDpSpS-Ca had excellent bioavailability when compared to CaCO 3 , calcium lactate, and d -calcium gluconate. This study revealed the calcium-binding mechanism of phosvitin phosphopeptide, and suggested that EDDpSpS-Ca has the potential to be a novel, efficient, and promising calcium supplement.
研究领域:
营养学
·
生物化学
✓ 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）