Journal of Nano Research
·
2022
·
IF 1.78
Rusul Mohammed Abdallah,Raad M.S. Al-Haddad
There are many methods for synthesizing magnetite nanoparticles. Most methods take a long time, and the result is undesirable. In this paper a green method was used to synthesize nanoparticles because it takes a short time and is both straightforward and eco-friendly. It is done by adding : =1:2 molar ratio solution with different amounts of extract and different amounts of NaOH solution for 20 min at different temperatures, in hotplate stirrers, to control their relative size. UV-Vis spectroscopy, vibrating sample magnetometer technique (VSM), transmission electron microscopy (TEM), and X-ray diffraction (XRD) were used to characterize the magnetite nanoparticles. The result confirms that the changes in amounts of NaOH and extract led to a change in the pH of a solution and that the increase in amounts of the extract caused the low addition of NaOH. These changes influenced the process of synthesis and characterization. The Uv-vis analysis confirms that the surface plasmon resonance had a highly visible brad peak in the 290–460 nm range, as well as a peak shift to shorter wavelengths (blue shift) with a pH change and a peak shift to longer wavelengths (red shift) with a temperature change. TEM imaging confirms that all the synthesized had a spherical shape with size changed according to a parameter change of within 40–9 nm. Magnetic analysis showed the magnetite nanoparticles synthesized have smaller sizes and are superparamagnetic with the influence of particle size on the magnetic properties, including Hc, Ms, and Mr.
研究领域:
材料科学
·
纳米技术
·
化学
·
物理学
✓ 已验证
DOI
高影响因子
CHEMOSPHERE
·
2019
·
IF 5.108
Qi Zhang,Lei Wang,Baiyang Chen,Yi Chen,Jun Ma
Understanding ultraviolet photolysis induced by low pressure mercury lamp that emits both 254 nm ultraviolet (UV 254 ) and 185 nm vacuum UV (VUV 185 ) is currently challenging due to the copresence of multiple direct and indirect photochemical processes involving a series of highly-reactive radicals. Herein we examined the formation and transformation of H 2 O 2 in water, which is both a precursor and a product of radicals, under various pH and dissolved oxygen (DO) conditions. The trends show that H 2 O 2 increased rapidly at early stage and then remained steady in DO-rich water or declined somewhat in DO-poor water, ultimately leading to higher steady-state H 2 O 2 in DO-rich water. The maximum H 2 O 2 contents nonetheless were similar among waters with different DO, suggesting that H 2 O 2 in this system was mostly generated by hydroxyl radical ( OH) recombination, which is an oxygen-independent H 2 O 2 formation pathway, rather than by reduced oxygen via hydrogen atom (H ) or hydrated electron (e aq − ), which is an oxygen-dependent pathway. Increasing pH (from 6.3 to 10.0) or bicarbonate dosage dramatically decreased H 2 O 2 formation too. Mathematically, the fates of H 2 O 2 as a function of pH, DO, and time were well modeled (R 2 ≥ 0.92), in which the rates of H 2 O 2 formation and destruction were greater in DO-poor water than those in DO-rich water. In addition, we found that the steady-state concentrations of OH used for degradation of p-chlorobenzoic acid, an OH probe, correlated well with the OH levels used for H 2 O 2 formation (R 2 = 0.98). These results hence may help better understand the UV/VUV process via H 2 O 2 evolutions.
研究领域:
环境科学
·
化学
✓ 已验证
DOI
PubMed
高影响因子
Journal of Materials Chemistry C
·
2025
·
IF 5.1
Zhengyang Gao,Shi Li,Yong Qi,Xianfei Cao,Wenbin Niu,Suli Wu,Shufen Zhang
Photonic crystal microbeads with symmetrical structures exhibit non-iridescent colors, making them valuable as stable and vibrant colorants. However, their brightness is limited by small refractive index contrast. Enhancing this contrast is key to achieving more vivid structural colors. Herein, CeO 2 @SiO 2 photonic crystal microbeads (10-30 μm) with a high refractive index were successfully fabricated by the microfluidic method. By tuning the diameter of CeO 2 @SiO 2 colloidal particles from 160 nm to 265 nm, blue, green, and orange-red microbeads pigments were successfully fabricated, exhibiting vivid structural colors across a wide viewing angle range of 0° to 75°.Interestingly, films composed of these microbeads pigments and polymers showed bright, angle-independent colors and strong UV absorption. These CeO 2 @SiO 2 microbeads can not only be used as pigments for bright, omnidirectional structural colors but also have potential applications in various fields that require UV-shielding, such as color lenses, decorative coatings, and cosmetics.
研究领域:
材料科学
·
光学材料
·
纳米技术
·
颜料技术
·
光子晶体
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY A-CHEMISTRY
·
2017
·
IF 2.625
Jianmin Chen,Qiaoyuan Fang,Shiqi Liu,Guozhong Yang,Yunhua Gao
In order to design more stable formulations for glabridin and to assess the degradation of glabridin as a pollutant in the environment, the photodegradation of glabridin by UV irradiation was investigated. The influences of initial concentrations, solvents, pH values, H 2 O 2 , metal ions and UV absorbers on the photolysis of glabridin were all taken into account. It was found that the photodegradation rate constant increased when decreasing the initial glabridin concentrations, and the degradation of glabridin followed pseudo first-order reaction kinetics. Glabridin in pure methanol exhibited the highest stability with lowest rate constant of 0.357 ± 0.054 h −1 , compared to other saturated monohydric alcohols, and degradation seemed to be affected by the polarity of the solvent. From the experiments to test the effect of pH values on the photolysis of glabridin, we found that glabridin was unstable in both acidic and alkaline solutions. In the UV/H 2 O 2 process, the photodegradation increased with increasing the initial H 2 O 2 concentration. Addition of metal ions such as Fe 2+ , Fe 3+ and Cu 2+ to the glabridin solutions also induced faster degradation compared to negative control, and the degradation processes were dependent on the UV irradiation. In order to stabilize glabridin in the UV process, UV absorbers were added to the solutions. The results suggested that cinnamate and phenyl salicylate could protect glabridin against UV irradiation effectively. More interestingly, we demonstrated that photodegradation products of glabridin would be a valuable source for discovering new tyrosinase inhibitors with higher activity and better stability.
研究领域:
环境科学
·
药理学
·
化学
✓ 已验证
DOI
高影响因子
WATER RESEARCH
·
2022
·
IF 13.4
Huimei Pan,Yuanxi Huang,Juan Li,Boqiang Li,Yang Yang,Baiyang Chen,Rongshu Zhu
Haloacetaldehydes (HALs) are the third largest disinfection by-product (DBP) ubiquitously detected in finished drinking water and have relatively higher toxicity than currently regulated DBPs. To efficiently alleviate them, this study investigated a green, chemical-free technology by using ultraviolet/vacuum ultraviolet (UV/VUV) on degrading three refractory chlorinated HALs (Cl-HALs). The results indicate that the rates of Cl-HALs decomposition in tap water irradiated by UV/VUV were 23–70 times higher than those irradiated by UV, proving that VUV instead of UV played the key role in degrading Cl-HALs. Increasing Cl-HALs dosage, pH, and dissolved oxygen (DO) all decreased the Cl-HALs degradations significantly, and the rates in tap water were apparently lower than those in ultrapure water. Unlike previous studies, this study proved that both oxidation and reduction were present during the VUV process. Photooxidation via oxidative radicals like •OH mineralized Cl-HALs, leading to substantial drops of total organic carbon ; photoreduction via reductive radicals like •H dehalogenated Cl-HALs, resulting in formation of considerable intermediate organics (e.g., formic acid and acetic acid). No matter what pathway, the mass balances of chlorine were always maintained, meaning that dehalogenation occurred instantaneously rather than sequentially. Although the overall photodegradation rates dropped with rising pH and DO, photoreduction was increased with rising pH while photooxidation was elevated with rising DO. The results hence provide insights to better understand the VUV technology in controlling micropollutants in water.
研究领域:
环境科学
·
水处理技术
✓ 已验证
DOI
PubMed
高影响因子
International Journal of Environmental Research and Public Health
·
2018
·Vol. 15
·期 7
·1520
·
IF 2.145
Zhuqiu Sun,In-Sun Kang,Qianyuan Wu,Jinying Xi,Hongying Hu
Ultraviolet (UV) photodegradation is increasingly applied to control volatile organic compounds (VOCs) due to its degradation capabilities for recalcitrant compounds. However, sometimes the UV photodegradation products are also toxic and can affect human health. Here, 10 VOCs at 150~200 ppm in air were treated using a laboratory-scale UV reactor with 185/254 nm irradiation, and the biotoxicity of their off-gas was studied by investigating their off-gas absorption solutions. The CO2increase and VOC decrease were 39~128 ppm and 0~42 ppm, respectively, indicating that the VOCs and their products were mineralized in off-gas absorption solutions. The total organic carbon (TOC) of the absorption solutions are 4~20 mg∙L−1. Luminescent bacteria andDaphnia magnawere used to detect the acute toxicity, and anumuassay was used to determine the genotoxic potential. Trichloroethylene showed a highest toxicity to luminescent bacteria, while chlorobenzene had the lowest toxicity. Water-soluble UV photodegradation products for styrene are very toxic toDaphnia magna. In theumuassay, the genotoxicities of off-gas absorption solutions of trichloroethylene, methylbenzene, ethyl acetate, butyl alcohol, and styrene were 51.26, 77.80, 86.89, 97.20, and 273.62 mg (4-NQO)·L−1respectively. In addition, the analysis of the genotoxicity/TOC and intermediates products indicated that the off-gas absorption solutions of styrene, trichloroethylene, and butyl alcohol contain many highly toxic substances.Keywords:VOCs;UV photodegradation;biotoxicity;luminescent bacteria;Daphnia magna
研究领域:
环境科学
·
毒理学
✓ 已验证
DOI
PubMed
高影响因子
POLYMER SCIENCE SERIES B
·
2022
·Vol. 64
·期 5
·644-650
·
IF 1.023
Zheng X. C.,Wu C. L.,Xiong J.,Lei H.
Abstract Poly( N -isopropylacrylamide) was grafted onto the surface of polypropylene by a two-step surface photo-grafting method using benzophenone as a photosensitizer to impart surface temperature sensitivity to polypropylene. The structure of graft-copolymer was characterized by infrared spectroscopy and scanning electron microscopy. Its temperature sensitivity was investigated by modulated differential scanning calorimetry and surface water contact angle determination. The effects of initiator concentration, photoreduction time, monomer concentration and light exposure time on grafting rate are discussed. The results showed that graft-copolymer is temperature-sensitive hydrophilic/hydrophobic, and its low critical solubility temperature is around 33°C. The grafting rate could be increased by increasing the initiator concentration, monomer concentration, extending the photoreduction time and irradiation time; and the grafting rate could be controlled by adjusting these four factors.
研究领域:
材料科学
·
高分子化学
✓ 已验证
DOI
高影响因子
Frontiers in Materials
·
2022
·
IF 3.985
Xiong Zhengrong,Zhang Hang,Zhou Yan,Yang Yuming
Polycarbonate-based polyurethanes (PCU) are frequently used in airship envelope materials because of its outstanding mechanical performances and aging resistance. However, the surface of PCU is likely damaged during processing and operating and the emerged minuscule cracks will lead to deterioration of perfomances for airship’s envelope materials. Herein, self-healing PCU/polypyrrole nanoparticles (PPy) composites were prepared by solution blending and quick healing of specific area for PCU was realized due to the high photo-thermal conversion merit of PPy. The results show that, the mechanical properties of PCU/PPy composites can be restored to more than 80% and the gas barrier properties can also be basically repaired when irradiating the destroyed surface using near-infrared light for only 60s. In addition, the ultraviolet visible (UV-vis) shielding performance of the PCU/PPy composites was enhanced significantly and the UV-vis transmittance was less than 14% and 2% with 0.25wt% and 0.5wt% PPy, respectively. Meanwhile when 0.25wt% PPy was added, the tensile strength increased from 17.9MPa to 21.7 MPa and the elongation at break increased from 647% to 829%. Besides, the thermal decomposition temperature at 5wt% loss increased from 277.8°C to 300.7°C and 304.88°C with 0.25 wt% and 0.5 wt% PPy, respectively. The prepared composites show promising application in aerospace domain.
研究领域:
材料科学
·
航空航天工程
✓ 已验证
DOI
高影响因子
BIOORGANIC CHEMISTRY
·
2020
·
IF 4.831
Jiaguo Li,Dian Xiao,Fei Xie,Wei Li,Lei Zhao,Wei Sun,Xiaohong Yang,Xinbo Zhou
Antibody-drug conjugates (ADCs) are being developed worldwide with the potential to revolutionize current cancer treatment strategies. However, off-target toxicity caused by the instability of linkers remains one of the main issues to be resolved. Developing a novel photocontrol-ADC with good stability and photocontrolled release seemed to be an attractive and practical solution. In this study, we designed, for the first time, a novel ultraviolet (UV) light-controlled ADC by carefully integrating the UV-cleavable o -nitro-benzyl structure into the linker. Our preliminary work indicated that the ADC exhibited good stability and photocontrollability while maintaining a targeting effect similar to that of the naked antibody. Upon irradiation with UV light, the ADC rapidly released free cytotoxins and exerted significant cytotoxicity toward drug-resistant tumor cells. Compared to those of the unirradiated cells, the EC 50 values of ADCs increased by up to 50-fold. Furthermore, our research confirmed that the degradation products of unirradiated ADC, Cys- 1a, were relatively less toxic, thus potentially reducing the off-target toxicity caused by nonspecific uptake of ADCs. The novel design strategy of UV light-controlled ADCs may provide new perspectives for future research on ADCs and promote the development of photocontrol systems.
研究领域:
癌症治疗
·
药学
·
分子生物学
·
化学工程
✓ 已验证
DOI
PubMed
高影响因子
Environmental Science-Water Research & Technology
·
2021
·Vol. 7
·期 3
·630-637
·
IF 4.251
Shixiang Wang,Zhuo Chen,Zhenran Wang,Yongsheng Fu,Yiqing Liu
UV/Fe2+/peracetic acid (PAA) as an efficient and novel advanced oxidation system was reported to produce reactive species (i.e., hydroxyl radicals (˙OH) and organic radicals) for triclosan (TCS) degradation, which is a representative of pharmaceutical and personal care products (PPCPs). The effects of initial pH, PAA dosage and common water matrix on TCS degradation were investigated. The results indicated that 1 μmol L−1 TCS was completely removed within 10 min at an optimum initial pH of 3.5, Fe2+ dosage of 10 μmol L−1, PAA dosage of 1 mmol L−1 and temperature of 25 °C. The presence of HCO3− and natural organic matter (NOM) showed obviously negative effect on TCS degradation, while NO3− strongly promoted the destruction of TCS. According to the detected nine reaction products, the probable degradation pathways of TCS by UV/Fe2+/PAA were proposed including ether bond cleavage, hydroxylation, dechlorination, dechlorination–hydroxylation and dehydrogenation.
研究领域:
环境科学
·
化学工程
✓ 已验证
DOI
高影响因子
SENSORS AND ACTUATORS B-CHEMICAL
·
2020
·
IF 7.1
Xu Ni,Jing Luo,Ren Liu,Xiaoya Liu
In this work, a one-step approach through UV-curing technology was developed to fabricate polyelectrolyte-based humidity-sensing coatings. The humidity-sensing coatings were prepared by the photo-polymerization of three monomers via UV irradiation: quaternary ammonium salt of 2-(dimethylamino)ethyl methacrylate (DEB) served as humidity-sensing monomer, methyl methacrylate (MMA) tailored the hydrophilicity/hydrophobicity of the coating, and 1,6-hexanediol diacrylate (HDDA) enhanced the stability and repeatability via crosslinking. The influence of the introduction of MMA and HDDA in the coating on the humidity-sensing performance was studied. The introduction of hydrophobic monomer and crosslinking agent could not only enhance the response and decrease the hysteresis of the sensing coating, but also improve the stability and repeatability of the coating at high relative humidity. Under optimized conditions, the prepared humidity-sensing coating showed a wide detection range (22 %–91 %RH), small hysteresis (2 %RH), and short response time (5 s) and recovery time (76 s). The bending test of the humidity-sensing coating showed that the sensing coating has good flexibility. The whole process is rather simple (one step), highly efficient (accomplished in several minutes), scalable, and environmental-friendly, which provides a promising strategy in fabricating flexible humidity-sensing devices.
研究领域:
材料科学
·
传感器技术
✓ 已验证
DOI
高影响因子
CHEMOSPHERE
·
2018
·
IF 4.427
Xinran Zhang,Jun He,Shuqi Xiao,Xin Yang
Microcystin-LR (MC-LR), a toxin produced by cyanobacteria, is very toxic and poses a threat to public health when entering water treatment works. In this study, UV/chlorine process, as an advanced oxidation process (AOP), has been demonstrated for effective elimination of MC-LR levels and associated toxicity. At a chlorine dose of 3.0 mg L −1 and UV fluence of 125 mJ cm −2 , MC-LR (initial concentration 1.0 μM) was reduced by 92.5%, which was much higher than 20.3% removal under UV irradiation alone and 65.1% removal during dark chlorination. Enhanced degradation was attributed by hydroxyl radicals (HO ) and reactive chlorine species (RCS), mainly Cl 2 - and ClO . Increasing chlorine doses or lowering pH favored MC-LR removal. Increased bicarbonate and natural organic matter concentrations inhibited MC-LR removal, but bromide ions enhanced MC-LR removal instead. MC-LR elimination rates in natural waters were roughly two times smaller than those in ultrapure water. The reactive radicals promoted hydroxylation of both diene of Adda moiety and double bond of Mdha moiety in MC-LR. UV exposure enhanced the dechlorination of chloro-MC-LR via the cleavage of C Cl bond. The toxicity was evaluated by a protein phosphatase (PP2A) inhibition assay. At a chlorine dose of 3.0 mg L −1 and UV fluence of 125 mJ cm −2 , the toxicity of the treated water was reduced by 75.0%, which was also higher than 25.7% and 46.7% removal under UV irradiation alone and during dark chlorination, respectively. These results highlight UV/chlorine is an efficient AOP for MC-LR degradation and detoxification.
研究领域:
环境科学
·
水处理工程
·
毒理学
✓ 已验证
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）