ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY
·
2019
·
IF 4.527
Xiaoyong Huang,Zhaoyang Yan,Kui Zhu,Shuangyang Ding
Ionizable strategies are routinely used to enhance the solubility and dissolution rates of various pharmaceuticals. These chemicals may directly affect aquatic environment once discharged from factories, hospitals or livestock farms. Here, we assessed the potential side effect of tetracyclines (TCs) on the development of zebrafish embryos. Tetracycline hydrochloride decreased water pH from 6.4 to 4.4 at 30 mg/L. Acidified water exceeded the tolerance of zebrafish embryos in pure water during the early ten hours post fertilization (hpf). Interestingly, we found that Ca 2+ in the embryo medium could increase the tolerance of embryos to acidified water. Furthermore, we found that the protection of Ca 2+ was not due to the formation of TCs-Ca 2+ complexes under acidic condition, based on spectral analysis. Meanwhile we showed that exogenous addition of Ca 2+ could inhibit the accumulation of Ca 2+ from the cytoplasm to the surface of embryos. These results may shed light on the strategies for protecting aquatic animals from acidic environments.
研究领域:
水生毒理学
·
环境科学
·
药理学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF DISPERSION SCIENCE AND TECHNOLOGY
·
2016
·
IF 1.112
Liqiang Zhu,Chuanzhuang Zhao,Dirong Gong
As an ionic cross-linker that can change the size of poly(N-isopropylacrylamide-co-acrylic acid) microgel, Ca2+ is applied as a trigger to demulsify microgel-stabilized oil/water Pickering emulsions. The influence of Ca2+ induced intra-particle ionic cross-linking and inter-particle aggregation on the stability of microgel-stablized “Pickering” emulsion is described. At low and mediate concentration of Ca2+, ionic cross-linking can change the internal elasticity of the microgel, and cause the coarsening of the oil droplets. At high concentration of Ca2+, microgels flocculate due to the salt out effect and the emulsion is destabilized. This work provide a facile method to control the stability of the Pickering emulsions at ambient condition.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
Royal Society Open Science
·
2018
·Vol. 5
·期 8
·
IF 2.504
Liuyi Ren,Hang Qiu,Wenqing Qin,Ming Zhang,Yubiao Li,Penggang Wei
The existence of metal ions should not be ignored in both hydrometallurgy and flotation. In this study, the effects of Ca2+, Mg2+ and Fe3+ on the flotation performance of cassiterite using octanohydroxamic acid (OHA) as the collector were investigated by micro-flotation tests, X-ray photoelectron spectroscopy (XPS), Fourier transform infrared (FTIR) spectroscopy, contact angle, zeta (ζ) potential measurements and atomic force microscopy (AFM) imaging. The results of the flotation and contact angle experiments showed that the addition of Ca2+, Mg2+ and Fe3+ significantly decreased both the recovery and contact angle of cassiterite with pH ranged from 6.0 to 12.0 in the presence of OHA collector. ζ-Potential measurements, solution chemistry analysis and FTIR measurements indicated that the flotation recovery of the cassiterite declined due to the CaOH+, MgOH+ and Fe(OH)3 sites on the cassiterite surface. XPS results indicated that the chemisorption of OHA and calcium ions on the cassiterite surface finally changed its chemical properties. The AFM images also revealed that new species Fe(OH)3 of Fe3+ formed and adsorbed on the cassiterite surface at pH 9.0. The adsorption of Fe(OH)3 reduced the adsorption of OHA on the cassiterite surface, thus the hydrophobicity of cassiterite was deteriorated.
研究领域:
矿物加工工程
·
表面化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
OPTICAL MATERIALS
·
2023
·
IF 3.9
Wei Liu,Shiqing Xu,Lei Lei
Lanthanide doped Sc 2 (MoO 4 ) 3 upconversion (UC) crystals showed distinct negative thermal quenching effect, which show promising applications in the temperature sensing field. However, it is still valuable to develop novel routes to enhance the room temperature UC intensity. Herein, the UC intensity of the Yb/Er (Ho) doped Sc 2 Mo 3 O 12 crystals were significantly enhanced by doping Ca 2+ ions. The incorporation of Ca 2+ ions can break the crystal symmetry around the activators and then promote the 4f-4f transitions followed by the enhanced UC. Especially, the UC intensity of the Sc 2 Mo 3 O 12 :20Yb/1Ho/20Ca was about 100 times than that of Sc 2 Mo 3 O 12 :20Yb/1Ho phosphors. Furthermore, the thermally couple levels based temperature sensing performance was improved after doping Ca 2+ ions. Our results may promote the exploration of novel scheelite structural compounds with superior UC properties.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL RESEARCH IN CHINESE UNIVERSITIES
·
2014
·Vol. 30
·期 3
·362-367
·
IF 1.119
Cao Li,Jia Chunman,Zhang Qi,Chen Da,Zhang Chunyan,Qian Yaao
A fluorescent probe with a coumarin moiety bound to rhodamine 6G hydrazide( 1 ) was synthesized. Its sensing behavior toward various metal ions was investigated with fluorescence methods. Compound 1 displays different fluorescence emission responses to Al 3+ and Ca 2+ at the same excitation wavelength in the visible light region, while no changes occur after the addition of other metal ions. The binding ratios of the complexs of 1 -Al 3+ and 1 -Ca 2+ are both 2:1 according to the Job plot and high resolution mass spectrometer(HRMS) experiments. Moreover, emission spectrum of 1 -Ca 2+ complex and absorption spectrum of the rhodamine dyes overlap largely. When Al 3+ was added to the 1 -Ca 2+ system, calcium in complex 1 -Ca 2+ can be displaced by Al 3+ , resulting in the output of another ratiometric sensing signal, which demonstrates that the 1 -Ca 2+ complex can be served as a new and effective fluorescence resonance energy transfer(FRET) donor for rhodamine derivatives.
研究领域:
化学传感器
·
荧光共振能量转移
✓ 已验证
产品关联
DOI
高影响因子
ENZYME AND MICROBIAL TECHNOLOGY
·
2019
·
IF 3.553
Yue Zhang,Wenhui Sun,Nora Mohamed Elfeky,Yuepeng Wang,Dongying Zhao,Hao Zhou,Jingyun Wang,Yongming Bao
Lipase ZC12, a cold-adapted lipase derived from Psychrobacter sp. ZY124, can be effectively activated by Ca 2+ . Inspired by this significant property, we developed a novel immobilized lipase ZC12/Ca 3 (PO 4 ) 2 hybrid nanoflowers (LHNs). The LHNs have been characterized as a regular hierarchical flowerlike structure nanoflowers by scanning electron microscopy (SEM). Compared with free lipase ZC12, the LHNs exerted enhanced enzymatic activity of 206% and 2.31-fold in k cat / K m value, especially high specific activity at low temperature. After 7 successive cycles, the LHNs could still maintain its initial activity, demonstrating superior durability than the free lipase ZC12. Meanwhile, its stability basically kept unchanged in a wide range of temperature and pH. Finally, fructose laurate was transformed by the LHNs with 57.39% conversion rate which is twice as much as the free lipase. To sum up, these results validated that LHNs could emerge as an efficient immobilized lipase and possess the promising potential for practical applications.
研究领域:
生物化学
·
酶工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
MODERN PHYSICS LETTERS B
·
2024
·
IF 1.8
Jiaqi Li,Jianyu Li,Bin Xu,Zhiyi Ren,Shixiao Yan,Di Zhang,Meng Wang,Xiaoliang Sun,Chi Liu,Jing Feng
This work aims to investigate the influence of Ca 2 + doping on the infrared emission properties of DyTa 3 O 9 ceramics. DyTa 3 O 9 is considered a promising high-temperature thermal protection material due to its low thermal conductivity and good high-temperature stability. However, there is currently no research on the infrared radiation performance of such materials. We synthesized DyTa 3 O 9 ceramics with different Ca 2 + doping concentrations using the solid-phase reaction method and systematically investigated the effect of doping concentration on the infrared emissivity of DyTa 3 O 9 ceramics. When Ca 2 + is doped into the DyTa 3 O 9 lattice, the original Dy elements are replaced by Ca, resulting in an increase in lattice constants and enhanced lattice distortion. The doping of Ca 2 + introduces impurity energy levels, making it possible for some low-energy electron transitions, achieving an enhancement in infrared absorption and emission capabilities. When the Ca 2 + doping concentration reaches 7.5% mol, the average infrared emissivity in the 3–5 μ m and 8–12 μ m ranges are 0.85 and 0.92, respectively, representing a 19.7% and 21% increase compared to DyTa 3 O 9 . This novel high-infrared-emissivity ceramic holds great potential for applications in high-temperature energy conservation and aerospace thermal protection.
研究领域:
材料科学
·
陶瓷材料
·
光学材料
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2024
·
IF 5.1
Xiuyun Zhang,Mingnan Shangguan,Laijun Liu,Shenfeng Long,Tingting Wei,Guisheng Zhu,Yunyun Zhao,Huarui Xu
According to the literature reports, synthesis of Ba 1- x Ca x TiO 3 (BCT) ceramics with good microstructure and satisfactory dielectric property is still a challenge. So, a facile tartaric coprecipitation method in the study is proposed to prepare BCT fine powders with homogeneous morphology, high crystallinity and tetragonality. The effect of Ca 2+ doped concentration on microstructure and dielectric property was studied. Results showed that, the characteristics of the raw BCT powders greatly affected the microstructure and site occupancy of Ca 2+ in BT ceramics, which subsequently played a crucial rule on the dielectric performance. Owing to the good properties of the raw BCT powders, the as-obtained ceramics demonstrated good microstructure with uniform grain size of ∼1 μm, defined grain boundaries and densely packed without any cracks or pores. In addition, they also demonstrated much improved dielectric properties with good ε r , low tan δ , definite increase of Tc , suggesting they are compatible in application of MLCC with high performance.
研究领域:
材料科学
·
电子工程
✓ 已验证
DOI
高影响因子
Food Biophysics
·
2015
·Vol. 10
·期 4
·447-455
·
IF 1.63
Cao Liwei,Su Sisi,Regenstein Joe M.,Xiong Shanbai,Liu Ru
The role of Ca 2+ in gelation of myosin extracted from silver carp ( Hypophthalmichthys molitrix ) was investigated. Compared with the control, myosin with CaCl 2 showed higher turbidity and larger particle size, indicating that CaCl 2 contributed to myosin aggregation. Addition of CaCl 2 decreased the myosin thermostability and promoted the unfolding of myosin α-helical structure during heating. Moreover, CaCl 2 could increase surface hydrophobicity at low temperatures (20–40 °C) and promoted hydrophobic interactions. Meanwhile, it decreased the temperature of disulfide bond formation by about 10 °C. Addition of 10–40 mM CaCl 2 favored activation of the Ca 2+ -ATPase activity at 20 to 30 °C, but not obvious with elevated temperatures. Ca 2+ -ATPase activity of myosin was undetectable when heated above 60 °C because of severe structural damage of myosin heads. G’ at both the first and second peaks increased with increasing CaCl 2 concentration. Therefore, CaCl 2 was beneficial for gelation of myosin by inducing the unfolding of myosin and enhancing disulfide bonds along with hydrophobic interactions between neighboring myosin molecules.
研究领域:
食品科学
·
生物化学
·
蛋白质化学
✓ 已验证
DOI
高影响因子
APPLIED MICROBIOLOGY AND BIOTECHNOLOGY
·
2020
·Vol. 104
·期 16
·7079-7091
·
IF 3.53
Wang Shengli,Han Jing,Xia Jiale,Hu Yanru,Shi Liang,Ren Ang,Zhu Jing,Zhao Mingwen
Abstract Identifying new and economical means to utilize diverse lignocellulosic biomass is an urgent task. Ganoderma lucidum is a well-known edible and medicinal basidiomycete with an excellent ability to degrade a wide range of cellulosic biomass, and its nutrient use efficiency is closely related to the activity of extracellular cellulase. Intracellular nicotinamide adenine dinucleotide (NAD + ) biosynthesis is controlled in response to nutritional status, and NAD + is an essential metabolite involved in diverse cellular processes. Nicotinamide mononucleotide adenylyltransferase (NMNAT) is a common enzyme in three NAD + synthesis pathways. In this study, a homologous gene of nmnat was cloned from G. lucidum and two G. lucidum overexpression strains, OE::nmnat4 and OE::nmnat19, were constructed using an Agrobacterium tumefaciens -mediated transformation method. The G. lucidum nmnat overexpression strains showed obviously increased colony growth on different carbon sources, and intracellular Ca 2+ concentrations in the G. lucidum OE::nmnat4 and OE::nmnat19 strains were increased by 2.04- and 2.30-fold, respectively, compared with those in the wild-type (WT) strains. In the G. lucidum OE::nmnat4 and OE::nmnat19 strains, endo- β -glucanase (CMCase) activity increased by approximately 2.8- and 3-fold, while β -glucosidase ( p NPGase) activity increased by approximately 1.9- and 2.1-fold, respectively, compared with the activity in the WT strains. Furthermore, overexpression of NAD + synthesis pathways was found to elicit cellulase production by increasing the intracellular Ca 2+ concentration. In summary, this study is the first to demonstrate that increased intracellular NAD + contents through overexpression of the nmnat gene of NAD + synthesis pathways may increase cellulase production by increasing intracellular Ca 2+ concentrations in G. lucidum . Key points
The concentration of NAD
+
influences cellulase production in G. lucidum.
The concentration of NAD
+
influences the intracellular Ca
2+
concentration in G. lucidum.
The concentration of NAD
+
influences cellulase production by eliciting a change in intracellular Ca
2+
in G. lucidum.
研究领域:
微生物学
·
生物技术
·
酶学
✓ 已验证
DOI
PubMed
高影响因子
MINERALS ENGINEERING
·
2024
·
IF 4.9
Yiwen Hu,Jieliang Wang,Zhao Cao,Xu Wu,Wenda Lu,Weiwei Wang,Wenli Liu
Bastnaesite is an important strategic resource. Since the calcium-bearing gangue minerals in the pulp can dissolve and release Ca 2+ ions, Ca 2+ ions and sodium silicate have a co-depression effect on bastnaesite flotation, which will affect the separation and purification of bastnaesite. In this study, the mechanism of eliminating the co-depression effect using ethylene diamine tetraacetic acid (EDTA) was studied by micro-flotation, bench-scale flotation, zeta potential, X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM)–energy spectrometry (EDS), contact angle and DFT calculations measurements. Micro-flotation results show that the addition of EDTA can effectively eliminated the co-depresses effect of Ca 2+ ions and sodium silicate. Bench-scale flotation tests showed that a high-quality rare earth (REE) ore concentrate with higher grade and recovery (62.35 % and 62.08 %, respectively) could be enriched by adding EDTA. Zeta potential results show that the combination of Ca 2+ ions and EDTA than with Ca 2+ ions alone, the surface potential of bastnaesite was significantly negative. XPS shows that EDTA prevented Ca-SiO 3 precipitation between Ca 2+ ions and sodium silicate by complexing Ca 2+ ions, which hindered the adsorption of sodium silicate to bastnaesite. SEM-EDS show that the addition of EDTA between Ca 2+ ions and sodium silicate, Ca 2+ ions had desorbed from the bastnaesite surface. Density functional theory (DFT) calculation showed that the adsorption energy of EDTA and Ca 2+ ions was much smaller than that of sodium silicate and Ca 2+ ions and Ca 2+ ions and mineral surface.
研究领域:
矿物学
·
浮选化学
✓ 已验证
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2019
·
IF 8.456
Yiqiong Liu,Yi Han,Haiqing Dong,Xunbin Wei,Donglu Shi,Yongyong Li
Engineering of cell surfaces holds promise in manipulating cellular activities in a physicochemical route as a complement to the biological approach. Mediated by Ca2+, a quick and convenient yet cytocompatible method is used to achieve surface engineering, by which polydopamine nanostructures can be in situ grown onto dendritic cell (DC) surfaces within 10 min. Ca2+, as the physical bridge between the negative cell surface and polydopamine, avoids the direct chemical polymerization of polydopamine onto the cell surface, critically important to maintain the cell viability. As a proof of concept in potential applications, this cell surface engineering shows a good control toward DC maturation. Upon surface polydopamine engineering, bone-marrow-derived DC exhibits a unique bidirectional control of maturation. The polydopamine structure enables effective suppression of DC activation by acting as an efficient scavenger of reactive oxygen species, a key signal during maturation. Conversely, an 808 nm laser irradiation can remotely relieve the suppressed state and effectively activate DC maturation by the photoheat effect of polydopamine (39 °C). The work provides an easily implemented, straightforward approach to achieve cell surface engineering, through which the DC maturation can be controlled.
研究领域:
生物医学工程
·
细胞生物学
·
材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）