SEPARATION AND PURIFICATION TECHNOLOGY
·
2023
·
IF 8.6
Jiayu Du,Decai Liu,Zhiyong Zhang,Huiying Ai,Ming-Lai Fu,Wenjie Sun,Baoling Yuan
The widespread use of chlorine during disinfection has led to the problems of disinfection by-products (DBPs). Recently, the combination of ultraviolet (UV, 254 nm) and vacuum ultraviolet (VUV, 185 nm) with chlorine has been considered a promising strategy to mitigate the formation of DBPs. This study systematically evaluated the efficacy of six different disinfection methods in abating humic acid (HA), a common precursor of DBPs (UV-Chlorine, VUV/UV-Chlorine, Chlorine-UV, Chlorine-VUV/UV, UV/Chlorine, and VUV/UV/Chlorine). Under 40 mJ/cm 2 UV fluence and 3 mg/L chlorine dose, the synergistic processes yielded DBP levels below 20 μg/L, whereas sequential disinfection resulted in DBP levels exceeding 100 μg/L. Additionally, there was no significant difference in the formation of DBPs between the two methods of chlorination followed by irradiation. However, for irradiation followed by chlorination, the addition of VUV led to an increase of 50 μg/L in trihalomethanes (THMs). As the irradiation time increased, the inclusion of VUV demonstrated enhanced control of DBP levels in the sequential disinfection process. Moreover, compared to UV/Chlorine, at 13 mg/L chlorine dose in VUV/UV/Chlorine process, the inclusion of VUV expedited the appearance of peak DBPs by two minutes and reduced the peak value by 25.6 %, but the DBP yield was 12.9 times higher than that at a chlorine dose of 3 mg/L. This study, comparing six combination disinfection methods, will provide deeper insights into precursor abatement and DBP control during drinking water disinfection.
研究领域:
环境科学
·
公共卫生
✓ 已验证
产品关联
DOI
高影响因子
ENVIRONMENTAL RESEARCH
·
2021
·
IF 6.498
Juan Li,Qi Zhang,Baiyang Chen,Lei Wang,Rongshu Zhu,Jie Yang
Understanding the formation and transformation of radicals generated by a low pressure mercury lamp emitting both 254 nm ultraviolet (UV 254 ) and 185 nm vacuum UV (VUV 185 ) is currently challenging due to the complexity of concurrent redox reactions occurring in this complex system. Because hydrogen peroxide (H 2 O 2 ) is a common product of both oxidizing and reducing radicals generated during the VUV irradiation process, monitoring the variations in H 2 O 2 levels can help us better understand the presence and relative dominance of different radicals. In this study, we systematically evaluated the effects of several selected anions on the formation of H 2 O 2 under a variety of pH and dissolved oxygen (DO) conditions. Results show that although addition of these anions inhibited the formation of H 2 O 2 , their H 2 O 2 -inhibition mechanisms are markedly different. At low concentrations (≤1.0 mg/L), chloride reduced the generation of H 2 O 2 primarily by consuming hydroxyl radicals (•OH); however, in high concentrations (11.0 mg/L), its light-screening effect was dominant. In comparison, the presence of bromide (≤1.0 mg/L) inhibited H 2 O 2 formation mainly by reacting rapidly with both •OH and H 2 O 2 . Carbonate and phosphorous species exerted influence mainly by consuming •OH. Along with irradiation, increasing pH significantly decreased H 2 O 2 levels, confirming that H 2 O 2 was formed mainly by •OH. In contrast, raising DO did not raise H 2 O 2 maximum yields, confirming that reducing radicals like aqueous electrons (e - aq ) and hydrogen atoms (•H) are not the key precursors of H 2 O 2 in this process. Mathematically, the evolutions of H 2 O 2 can be reliably modeled (R 2 ≥ 0.80) using a kinetics model incorporating H 2 O 2 formation and decomposition kinetics. The results of this study may contribute to better understanding the use of VUV technology in water/wastewater treatment.
研究领域:
环境科学
·
水处理技术
✓ 已验证
DOI
PubMed
高影响因子
MACROMOLECULAR CHEMISTRY AND PHYSICS
·
2025
·
IF 2.7
Danni Zhu,Zhe Li,Yuqing Wang,Wuxiang Chen,Nanshan Wu,Miaoming Huang,Hao Liu,Suqin He,Wanlin Xu,Wentao Liu
Polyurethane (PU) is widely used in production and daily life due to its excellent mechanical properties and strong plasticity. Long-term ultraviolet (UV) irradiation will cause PU aging and shorten its service life. However, preparing UV-resistant PU, which is colorless, transparent, and non-migratory, remains a challenge. This work introduced the reactive benzotriazole UV absorber (R455) into the PU molecular chain to prepare colorless and transparent intrinsic UV-resistant samples (PCU) by polymerization, using polycarbonate diol as soft segment, dicyclohexylmethane diisocyanate as hard segment, and 1,6-hexanediol as chain extender. The results show that the light transmittance of the UV-resistant PCU sample is about 90% in the visible light range. Moreover, the UV-resistant PCU shows excellent mechanical properties with elongation at break respectively higher than 580% and tensile strength transcending 50 MPa. After UV irradiation for 192 h, the tensile strength as well as the elongation at break of the PCU sample without R455 of the original values are respectively reduced to simply 60.8% and 62.7%. Whereas the introduction of R455 gives the PCU sample excellent UV resistance, the PCU sample with 1.5% R455 is respectively about 99.0% and 92.8%. These samples can be used in various fields with both UV resistance and optical requirements.
研究领域:
材料科学
·
高分子科学
·
涂层技术
·
光学材料
·
机械工程
✓ 已验证
产品关联
DOI
高影响因子
FIBERS AND POLYMERS
·
2017
·Vol. 17
·期 3
·396-401
·
IF 1.113
Zhang Haidong,Huang Yi,Wang Chenglong,Wang Lili,Shao Jianzhong
To decrease the pollution discharge and energy consumption resulting from textile finishing using the conventional pad-dry-cure process, a blue light-curable digital finishing for textile was innovatively proposed. Based on the mechanism of blue light curing technique, a combination of the blue light curing process and anti-UV finishing was established in this study. A blue light-curable anti-UV finishing solution containing oligomers, monomers, photoinitiators, and anti-UV agents was padded onto the surface of the cotton fabrics, and then cured to form a tough film under blue light irradiation. The ultraviolet protection factor (UPF) value of the finished cotton fabrics was 50, the top level of international standards, demonstrating excellent UV resistance. The finished cotton fabrics also showed good rubbing and washing durability, and acceptable handle. The integration of an anti-UV finishing with the blue light curing technique presents some unique advantages in terms of environmental protection and application potential.
研究领域:
纺织科学
·
环境科学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Environmental Sciences
·
2022
·
IF 6.796
Jie Xu,Yang Guo,Qian Yang,Xueling Bai,Runhua Lu,Menghui Liu,Zichen Kuang,Luo Zhang,Jing Li
Ultraviolet/persulfate (UV/PS) and Ultraviolet/hydrogen peroxide (UV/H 2 O 2 ) have attracted much attention in recent years as advanced oxidation processes for water treatment. However, it is not all clear how these two methods affect the formation of cyanogen chloride (CNCl) in the subsequent water chlorination process. In this study, it was found that both UV/H 2 O 2 and UV/PS pre-oxidation promoted the formation of CNCl in six actual water samples collected from urban rivers. Glycine, uric acid, arginine and histidine were investigated as the model compounds to explore the effects of different methods on the production of CNCl. The results showed that compared with chlorination alone, pre-oxidation by UV/H 2 O 2 and UV/PS can reduce the production of CNCl for glycine and uric acid by up to 95% during post-chlorination process. However, they can greatly promote the formation of CNCl for arginine and histidine by up to 120-fold. In a more detailed investigation, pre-oxidation of histidine formed highly reactive intermediates to chlorine, leading to increased CNCl formation and chlorine consumption. The results showed that the precursors of CNCl was altered after pre-oxidation, and need to be re-evaluated.
研究领域:
环境科学
·
水污染控制工程
✓ 已验证
DOI
PubMed
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
JOURNAL OF SOLID STATE CHEMISTRY
·
2024
·
IF 3.2
Wencheng Lu,Yaoguo Shen,Qiong Wu
The SO 4 tetrahedral group exhibits a low degree of polarization anisotropy, leading to a minimal level of birefringence of sulfates. Our report introduces a novel sulfate compound, RbY(SO 4 ) 2 ·4H 2 O, which exhibits exceptional birefringence in deep ultraviolet sulfates. This crystal possesses dimensions of 6 mm × 4 mm × 1 mm and was synthesized using a straightforward technique involving the evaporation of an aqueous solution. The structure of this substance is characterized by a unique arrangement of SO 4 tetrahedra YO 9 polyhedra, and H 2 O molecules. Each SO 4 moiety contribution two oxygen atoms to share edges with a neighboring YO 9 polyhedron, resulting in significant deformation of these groups. The unique arrangement of edge-sharing arrangement in RbY(SO 4 ) 2 ·4H 2 O results in a birefringence of about 0.045@546 nm. This sets a new record for sulfates in the deep ultraviolet range that have similar non-π-conjugated anionic groups. We elucidate UV–Vis–NIR diffuse-reflection, IR spectra, transmission spectra, and conduct theoretical calculations. These fascinating discoveries will improve our understanding of sulfates and provide valuable insights for studying deep-UV sulfates with strong birefringence.
研究领域:
材料科学
·
晶体学
✓ 已验证
产品关联
DOI
高影响因子
Materials
·
2024
·Vol. 17
·期 3
·671
·
IF 3.1
Yongneng Xiao,Shaoyi Hou,Zhenhuai Yang,Xingxing Huang,Yuanjun Guo,Siyu Ji,Xiaochan Huang,Fengshuang Wang,Qiang Hu,Xiaodong Guo
Tb3+-activated LTA zeolite-derived boro-aluminosilicate glass samples with a composition of xTb2O3-68(Na2O-Al2O3-SiO2)–32B2O3(x = 0.2, 1.0 and 10 extra wt%) were prepared using the melt-quenching method. The emission spectra recorded upon ultraviolet (UV) excitation with two different wavelengths of 193 and 378 nm showed blue light (5D3to7FJ=6,5,4and5D4to7F6transitions of Tb3+) and green light (5D4to7F5transition of Tb3+) emissions with comparable intensities up to a Tb3+concentration of 10 extra wt%. Of note, the mean decay times of the green luminescence of the glass samples were relatively fast (<20 μs). The synthesized glass has potential in applications concerning UV imaging, UV detection, and plasma display panels.
研究领域:
材料科学
·
光学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Science China-Chemistry
·
2021
·Vol. 64
·期 7
·1184-1191
·
IF 9.445
Gao Mengen,Wu Hongping,Yu Hongwei,Hu Zhanggui,Wang Jiyang,Wu Yicheng
Deep-ultraviolet (UV) nonlinear optical (NLO) crystals with excellent performances are of great importance in laser science and technology. However, to design and synthesize an ideal deep-UV NLO material with a balance between second harmonic generation (SHG) response and UV cut-off edge is still a huge challenge. Herein, a new oxy-borate BaYOBO 3 (BaYBO) was designed and synthesized by substituting Be 2+ with Y 3+ from Sr 2 Be 2 B 2 O 7 . The BaYBO features a stable three-dimensional framework and satisfies the property balance between a large SHG response (~2.6×KH 2 PO 4 (KDP)) and a short UV cut-off edge (<190 nm) as a promising deep-UV NLO candidate. The study of structure-property relationship indicates that the large SHG response of BaYBO is mainly attributed to the coplanar arrangement and large number density of BO 3 triangles. These results demonstrate that substituting Be 2+ with Y 3+ cations is also a feasible strategy for developing new deep-UV NLO crystals.
研究领域:
材料科学
·
光学
✓ 已验证
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2024
·
IF 2.7
Shujuan Yu,Xiang Deng,Cailong Deng,Jing Xia,Qilong Li
In this paper, a novel broad-spectrum chitosan polymer carbon dots-based UV absorber ((CS-PCDs)-g-UV-0) was obtained by grafting UV-0 onto chitosan-based polymer carbon dots (CS-PCDs) through a simple green microwave method to achieve the macromolecular quantification of UV-0 UV absorbers. The products were characterized by means of IR spectroscopy, NMR carbon spectroscopy, UV absorption spectroscopy, TGA, and XPS. Finally, the UV absorber was applied to natural rubber (NR), and its anti-UV aging properties were systematically investigated by conducting UV-accelerated aging experiments on the carbonyl index, weight loss rate, contact angle, and SEM morphology of the NR materials added with (CS-PCDs)-g-UV-0 before and after aging. The results showed that after 28 days of aging of NR added with 2% (CS-PCDs)-g-UV-0, the increase in carbonyl index was considerably less significant than that of pure NR samples, as was the change in contact angle. According to the observations made by SEM, the addition of this (CS-PCDs)-g-UV-0 caused a significant delay in the occurrence of cracking on the surface of the material. In summary, a novel UV absorber is proposed in the present study to enhance the performance of NR in UV aging resistance.
研究领域:
材料科学
·
高分子化学
✓ 已验证
产品关联
DOI
高影响因子
Inorganic Chemistry Frontiers
·
2022
·Vol. 9
·期 10
·2298-2304
·
IF 7.779
Jiongquan Chen,Wenqi Jin,Yanhui Zhang,Yun Yang,Zhihua Yang,Shilie Pan
A new alkaline-earth and rare-earth borate fluoride, Ba10LuB18O32F13, the first example of borate in the Lu–B–O–F system, has been successfully synthesized in a high-temperature vacuum system. It crystallizes in the orthorhombic system, with the Fmm2 space group and the parameters a = 16.5749(6) Å, b = 16.7644(9) Å, c = 13.6222(6) Å, and Z = 4. It represents a new fundamental building block (FBB), [B9O22], with the notation 9:[2(4:2Δ + 2T) + T], in which two [BO3] triangles and two [BO4] tetrahedra are enclosed into a [B4O10] ring and every two [B4O10] rings are bridged by a [BO4] tetrahedron. The [B9O22] FBBs are further condensed into a 3D network with two types of channels that accommodate Ba2+ and Lu2+ cations. The UV cut-off edge is below 190 nm, indicating the application potential of Ba10LuB18O32F13 in the DUV region. Additionally, to further explore the structural novelty of Ba10LuB18O32F13, a comparison with all anhydrous borates with 18 boron atoms in their chemical formula was carried out. The fascinating results indicate that [B9O22] has been discovered for the first time, enriching borate fluoride structure chemistry.
研究领域:
材料科学
·
晶体学
✓ 已验证
产品关联
DOI
高影响因子
POLYMER DEGRADATION AND STABILITY
·
2025
·
IF 7.4
Xinqi Di,Xinyu Chen,Yujie Kang,Jing Yang,Yangming Zou,Jiang Jing,Jun Sun,Hongfei Li,Xiaoyu Gu,Sheng Zhang
The applications of polypropylene (PP) are severely limited by its flammability and poor resistance to UV aging. Melamine hydrogen bromide (MHB) and aluminum hypophosphite (AHP) are widely used as synergistic flame retardants. Hindered amine light stabilizers (HALS) are typically used as anti-UV agents for polyolefins. However, the direct combination of acidic MHB and basic HALS induces antagonistic interactions, leading to a deterioration in material performance. In this work, antagonism is mitigated by coating MHB with polysiloxane (Si-MHB). Moreover, the polysiloxane layer can improve the compatibility between the flame retardant and PP, thereby enhancing flame retardancy and mechanical properties. PP composites containing Si-MHB, AHP, and HALS derivative were prepared. After 60 h of UV exposure, the surface of PP/Si-MHB/AHP/HALS119 remained relatively smooth with some shallow cracks. The water contact angle was maintained at 92°, and the carbonyl index decreased to 10.45, pointing out that the degree of photodegradation was significantly lower than that observed in the control samples. Besides, the limiting oxygen index (LOI) of PP/Si-MHB/AHP/HALS119 reached up to 26.5 %. After 60 h of UV irradiation, LOI decreased to 24.8 % and still maintained UL-94 V-0 rating, the tensile strength and impact strength decreased by 7 % and 10.2 %, which was a significantly lower reduction compared to the control samples. The above results demonstrate that the coating polysiloxane can effectively mitigate the antagonistic interactions between MHB and HALS119, effectively enhancing the UV aging resistance, flame retardancy, and mechanical properties of PP composites.
研究领域:
材料科学
·
高分子化学
✓ 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）