PROPELLANTS EXPLOSIVES PYROTECHNICS
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2023
·Vol. 48
·期 7
·e202200317
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IF 1.8
Jian Guan,Huan Peng,Yulan Song,Bo Jin,Rufang Peng
The thermal decomposition of Hexanitrohexaazaisowurtzitane CL-20/HMX-ammonium formate functionalized graphene oxide (Am-GO) composites was studied using an isothermal decomposition dynamics research instrument to explore the effects of Am-GO on the stability of CL-20/HMX co-crystal. The gas pressure-time curve generated by thermal decomposition reaches the decomposition inflection point at a decomposition degree of 85 %. Compared with CL-20/HMX co-crystal, the decomposition extent corresponding to the inflection point of the thermal decomposition curve of the composites increases. The activation energies of the composites before and after the inflection point of the pressure-time curve were 161.3 kJ/mol and 171.0 kJ/mol, respectively. The residual substances produced by the thermal decomposition of the composites were characterized by HPLC and FTIR. Results showed that CL-20 and HMX were decomposed before the inflection point of the decomposition pressure-time curve. However, the decomposition of CL-20 was completed before the inflection point, whereas that of HMX ran through the thermal decomposition process. The calculation results of thermal decomposition kinetics show that the addition of coating material increases the activation energy of co-crystal and stabilizes CL-20/HMX co-crystal.
研究领域:
材料科学
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化学动力学
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产品关联
DOI
高影响因子
JOURNAL OF MEMBRANE SCIENCE
·
2019
·
IF 7.015
Huayong Luo,Kelin Wu,Qin Wang,Tian C. Zhang,Hanxing Lu,Hongwei Rong,Qian Fang
We explore the feasibility of utilizing electro-responsive hydrogels as novel forward osmosis (FO) draw agents for desalination. The chemically cross-linked hydrogels were synthesized via free radical copolymerization of common acrylamide (AM) with strong anionic comonomer 2-acrylamido-2-methyl- 1 -propanesulfonic acid (AMPS). The morphology, chemical structure , water-adsorbing capacity, and water state of the hydrogels were characterized by scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FTIR), a swelling test, and differential scanning calorimetry (DSC). The water-swollen hydrogels exhibited electroresponsiveness as shrinking and expanding reversibly with the on-off switching of the electric field in an electrode contact system. The magnitude of hydrogels’ deswelling increased with the increase in the degree of swelling and applied voltages. This dehydration phenomenon was induced by the decrease in hydration power of microcounter ions due to the interaction with the electrodes by water electrolysis. The hydrogels were proved to be capable of generating a reasonable water flux of 2.76 L m −2 h −1 (LMH) from brackish water (2000 ppm NaCl solution) due to their high swelling pressure. In addition, the water flux was affected by the amount of hydrogel particles on the membrane surface. Importantly, the prepared hydrogels could effectively release around 71% of the adsorbed water at an applied voltage of 15 V for 40 min, and were able to maintain their water flux and water recovery performances up to three times regeneration. Results indicate that the electric field is an attractive alternative stimulus for extracting desirable water from the hydrogel draw agent in the FO desalination process.
研究领域:
环境科学
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材料科学
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产品关联
DOI
高影响因子
NEW JOURNAL OF CHEMISTRY
·
2023
·Vol. 47
·期 26
·12101-12108
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IF 3.3
Bin Li,Wenrui Hao,Jizhen Liu,Mengjing Zhou,Xiaojia Xu,Aolin Wu
Deep eutectic solvent (DES) was synthesized from choline chloride (ChCl) and acrylamide (AM), and P(AM-co-MA) hydrogels were prepared by adding different contents of maleic acid (MA) to DES by frontal polymerization. Fourier infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) were used to characterize the hydrogels at the microscopic level, and the swelling properties, mechanical properties, self-healing properties and electrical properties of the copolymerized hydrogels were also investigated. The results showed that the equilibrium swelling of the hydrogels was significantly enhanced with the increase of pH due to the addition of MA. The hydrogel with the addition of MA has self-healing properties that pure PAM does not have. In terms of electrical conductivity, the increase of MA makes the internal structure of the hydrogel more loose, which is conducive to the passage of free ions. And there is a significant effect of different temperatures and different crosslinker contents on the electrical conductivity. In summary, we prepared a P(AM-co-MA) hydrogel that can produce significant property changes in response to changes in the external environment, which is expected to expand the application of hydrogels in flexible electronic materials.
研究领域:
材料科学
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化学工程
·
生物医学工程
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产品关联
DOI
高影响因子
Sensors & Diagnostics
·
2023
·Vol. 3
·期 1
·135-146
·
IF 0
Ke Gao,Yuying Du,Na Pan,Xuewei Zhou,Liping Lu,Xiayan Wang
Cadmium (Cd) can cause cell oxidative stress and cytotoxicity. Few studies have focused on inhibitory effects on Cd2+-induced oxidative stress and related cytotoxicity. Scanning electrochemical microscopy (SECM) is a highly sensitive and non-invasive electrochemical analytical method. However, no information exists on inhibitory effects on Cd2+-induced cell oxidative stress using SECM technology. Herein, we studied the effects of ascorbic acid (AsA), zinc chloride (ZnCl2), and calcium chelator 1,2-bis (2-aminophenoxy) ethane-N,N,N′,N′-tetraacetic acid tetraethoxy methyl ester (BAPTA-AM) on cell oxidative stress with SECM. Subsequently, we studied the inhibitory effects of AsA, ZnCl2, and BAPTA-AM on Cd2+-induced cell oxidative stress. Consequently, 50 μmol L−1 AsA, 5 μmol L−1 ZnCl2, and 5 μmol L−1 BAPTA-AM did not produce reactive oxygen species (ROS) and had little effect on cell viability. However, they could significantly reduce Cd2+-induced excessive ROS and alleviate apoptosis (P < 0.01). Additionally, AsA had the strongest inhibitory effects on Cd2+-induced oxidative stress, followed by BAPTA-AM and ZnCl2. The inhibitory effects of AsA, ZnCl2, and BAPTA-AM on Cd2+-induced cytotoxicity might result from directly scavenging ROS and inhibiting oxidative stress-mediated signal transduction, enhancing antioxidant activities and maintaining cell membrane stabilities, and chelating excess calcium2+ (Ca2+) to hinder its subsequent signal transduction, respectively. Scavenging excessive ROS and inhibiting cellular oxidative stress-mediated signal transduction might be the most effective way to alleviate Cd2+-induced cytotoxicity. Our study provides empirical evidence on the inhibitory effects of AsA, ZnCl2, and BAPTA-AM as specialized inhibitors against Cd2+-induced cellular oxidative stress and cytotoxicity, providing precious ideas for detoxifying toxic environmental metal pollutants.
研究领域:
生物化学
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毒理学
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环境科学
✓ 已验证
DOI
MACROMOLECULAR CHEMISTRY AND PHYSICS
·
2024
·Vol. 225
·期 21
·2400141
·
IF 2.5
Lan Li,Yanjun Ren,Rugang Yao,Hong Yang
To solve the downhole problems correlated with clay hydration swelling and dispersion under high-temperature conditions, a 1-aminoethyl-3-vinylimidazolium bromide ([NVim]Br) and a [NVim]Br/acrylamide copolymer (poly([NVim]Br-co-AM)) are synthesized and used as inhibitors. The molecular structures of [NVim]Br and poly([NVim]Br-co-AM) are characterized by FT-IR and 1 H-NMR. The inhibition properties of [NVim]Br and poly([NVim]Br-co-AM) are evaluated by free swelling and dispersion tests, linear swelling, hot roll recovery experiments and thermogravimetric analyses.The inhibition mechanisms were revealed by X-ray diffraction, zeta potential, wettability analysis and ESEM observation. The results showed that both [NVim]Br and poly([NVim]Br-co-AM) has significantly superior inhibition performance compared with the common inhibitors KCl, polyether amine D230 and polyquaternium-7. Both [NVim]Br and poly([NVim]Br-co-AM) can resist 250 °C. [NVim]Br performed excellently in inihibiting both crystalline and osmotic swelling, which depended on the strong electrostatic adsorption and hydrogen bonds of imidazole cations and primary amine in [NVim] + . Poly([NVim]Br-co-AM) exerted excellent inhibition by minimizing osmotic swelling, reducing hydrophilicity and increasing clay bonding. The results are important for understanding the rational design of novel efficient inhibitors for drilling high-temperature shale formation.
研究领域:
化学工程
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2021
·Vol. 138
·期 25
·50601
·
IF 3.125
Wenlong Qin,Ruixuan Li,Hanxi Li,Guanfeng Jiang,Guowei Qin,Yang Wang,Jiang Yang
A Fe 3 O 4 nonaparticles coated with acrylamide/2-acrylamido-2-methyl-1-propanesulfonic acid copolymer(Fe 3 O 4 -Polymer NPs) was synthesized by emulsion polymerization. The structure of Fe 3 O 4 -Polymer NPs was then characterized by infrared spectroscopy, thermo-gravimetric analysis, and scanning electron microscopy. Meanwhile, the rheological properties of Fe 3 O 4 -Polymer NPs solution were systematically studied. The results showed that when dosage of hydrophobic Fe 3 O 4 -Oleic NPs is 10%, the synthesized Fe 3 O 4 -Polymer NPs was with the best viscosity enhancement performance, and the maximum saturation magnetization could reach to 20.0 emu/g. The apparent viscosity value of 5000 mg/L magnetic nano-composite solution was 154.6 mPa·s at 30°C. It shows strong viscosity enhancement ability and good temperature performance. Hence, it has great application potential in well stimulation of medium and high temperature oil and gas reservoirs.
研究领域:
材料科学
·
石油工程
✓ 已验证
DOI
高影响因子
APPLIED SURFACE SCIENCE
·
2024
·
IF 6.3
Bao Ren,Mingkang Xu,Jiaqiang Zhu,Zichang Xia,Chunfu Liu,Fanfei Min
The hydration characteristics of fine particles significantly influence the settling and dewatering of tailings. However, the current limited understanding of the micro-mechanisms governing the interactions between hydrophobic flocculants and fine particles hinders the optimization of tailings treatment technical. Through a combination of MD simulations, flocculation settling, and adsorption capacity analysis, the hydrophobic adsorption mechanism of P(AM-MAPTAC-TEMAc6) at the kaolinite/water interface was elucidated. Results suggested that hydrogen bonding and non-bond interactions synergistically drive the adsorption of P(AM-MAPTAC-TEMAc6) onto the kaolinite surface. As the mass concentration of P(AM-MAPTAC-TEMAc6) increased, the hydrophobic and associative interactions between the molecular chains enhanced the adsorption amount on kaolinite particles, leading to a notable decrease in the solution residual amount and the supernatant turbidity. P(AM-MAPTAC-TEMAc6) improved the dewatering performance of concentrated tailings by reducing the hydration film density on kaolinite surfaces, thus decreasing the compression layer thickness. The fluorocarbon side chains of P(AM-MAPTAC-TEMAc6) enhance the hydrophobic adsorption capacity of cationic side chains in the surface water region. Simultaneously, the associative interactions of the molecular chains in the bulk water region promote enhanced diffusion and migration, thereby strengthening the bridging mechanism between P(AM-MAPTAC-TEMAc6) and kaolinite particles, ultimately improving the settling and dewatering efficiency of the suspensions.
研究领域:
环境科学
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材料科学
✓ 已验证
DOI
高影响因子
SCIENCE OF THE TOTAL ENVIRONMENT
·
2021
·
IF 7.963
Ruijing Xu,Wenjie Zou,Ting Wang,Jun Huang,Zhijun Zhang,Chengyan Xu
Flocculation has been widely employed in treatment of mineral tailings and water management. In this study, a chitosan- graft -poly(acrylamide-dimethyl diallyl ammonium chloride) (Chi-g-P(AM-DMDAAC)) was synthesized in-house. The adsorption and interaction mechanisms of Chi-g-P(AM-DMDAAC) and an anionic polyacrylamide (APAM) in a two-step flocculation process of kaolinite were explored using settlement tests, zeta potential measurement, quartz crystal micro-balance with dissipation (QCM-D) and atomic force microscopy (AFM) technique. The type of primary flocculant was critical for the two-step flocculation process. The treatment of the kaolinite suspension using 1 mg/L of Chi-g-P(AM-DMDAAC) followed by adding 2 mg/L of APAM displayed more efficient flocculation performance. QCM-D results showed that three dissipative layers were assembled on model kaolinite surface after sequentially injecting 3.5 mg/L of Chi-g-P(AM-DMDAAC), 0.05 wt% kaolinite suspension and 2.5 mg/L of APAM. The above total adsorption amount (Δ f of −64.9 Hz) was much higher than that of using the two flocculants in reverse order (Δ f of −23.1 Hz). This result indicated that the adsorption layer of the positively charged Chi-g-P(AM-DMDAAC) on kaolinite surface provided active adsorption sites for APAM. Further AFM measurement confirmed that the average adhesion between the silicon tip adsorbed Chi-g-P(AM-DMDAAC) and model kaolinite surface in 2.5 mg/L APAM solution increased from 0.25 ± 0.1 nN to 4.2 ± 0.3 nN with the effective interaction range of 700 nm, which was stronger than that measured between a bare silicon tip and silica substrate in single-component-flocculant solutions. The highly efficient two-step flocculation process could be ascribed to the strong electrostatic attraction between the kaolinite and the oppositely charged Chi-g-P(AM-DMDAAC) and APAM. Findings in this study will benefit the development of environmentally friendly flocculant for mineral tailings and water treatment .
研究领域:
环境科学
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材料科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
COLLOIDS AND SURFACES A-PHYSICOCHEMICAL AND ENGINEERING ASPECTS
·
2024
·
IF 4.9
Lin Li,Hui Liu,Ran Wang,Qing Li,Lexin Zhang,Zhiwei Liu,Tifeng Jiao
To reduce mortality rate caused by life-threatening bacterial infections, advanced antibacterial materials have attracted widespread attention from researchers worldwide. In this study, the antibacterial P(AA-AM)/CA/GA nanofiber membranes with pH-responsive properties were successfully prepared by facile electrospinning technology. A series of characterizations of the obtained nanofiber membranes showed the addition of P(AA-AM) improves the surface wettability of the as-spun fibers in comparison to those of CA and CA/GA nanofiber membranes. High-temperature treatment was found to enhance the mechanical properties of the P(AA-AM)/CA/GA membranes due to the crosslinking reactions. The prepared P(AA-AM)/CA/GA nanofiber membrane exhibits a pH-responsive effect which is evident by the change in GA’s release rate in solutions with different pH values. The cellulose acetate (CA) spinning nanofiber structure formed by P(AA-AM) coated GA also extended the release process of GA and improved the antibacterial timeliness of nanofiber membranes. The antibacterial experiments on E. coli and S. aureus showed that the electrospun nanofiber membranes containing GA had potent antibacterial properties , which were further enhanced by increasing the GA content in the P(AA-AM)/CA/GA blends. This study provides an insight into the design and preparation of pH-sensitive antibacterial materials using facile electrospinning technology.
研究领域:
材料科学
·
生物学
·
医学
✓ 已验证
产品关联
DOI
高影响因子
Petroleum Science
·
2019
·Vol. 17
·期 1
·242-254
·
IF 1.846
Yan-feng Ji,Xu-long Cao,Yang-wen Zhu,Hui Xu,Xiu-zhi Sun,Hai-tao Li
Super high molecular weight copolymers of AM/NaA/AMPS were prepared by oxidation–reduction [OR-P(AM/NaA/AMPS)] and controlled radical polymerization [CR-P(AM/NaA/AMPS)]. The resulting copolymers were fully characterized, and the reaction conditions for their preparation were optimized. OR-P(AM/NaA/AMPS), CR-P(AM/NaA/AMPS), and conventional partially hydrolyzed polyacrylamide (HPAM) in brine solution were comprehensively characterized by thermogravimetric analysis, scanning electron microscopy, atomic force microscopy, and dynamic light scattering. OR-P(AM/NaA/AMPS) and CR-P(AM/NaA/AMPS) containing AMPS monomer showed better salt resistance, temperature tolerance, and viscosification property than the conventional HPAM polymer, making them more promising for enhanced oil recovery. Through comprehensive comparison and analysis, it was found that OR-P(AM/NaA/AMPS) was more conducive for high-temperature condition due to the existence of xanthone in OR-P(AM/NaA/AMPS). On the other hand, CR-P(AM/NaA/AMPS) was more suitable for high-mineral atmosphere, which could be attributed to its higher intrinsic viscosity.
研究领域:
化学工程
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材料科学
·
石油工程
✓ 已验证
DOI
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
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2022
·
IF 6.633
Yi Zong,Pan Xu,Haoyu Yue,Xinxue Li
To improve the stability of the polymers applied to profile control in high-temperature and high-salinity reservoirs, a water-soluble graft-copolymer HPMC-g-poly(AM/AA/APEG2400) was synthesized from hydroxypropylmethylcellulose (HPMC), acrylamide (AM), acrylic acid (AA), and allyl polyoxyethylene ether (APEG2400) via free-radical copolymerization using potassium persulfate (KPS) as the initiator. The molecular weight (M w ) of HPMC-g-poly(AM/AA/APEG2400) was controlled by the addition of the chain-transfer agent, sodium formate (SF), to the polymerization medium and was measured by capillary viscometry. Fourier transform infrared spectroscopy (FTIR), X-ray diffractometry (XRD), proton nuclear magnetic resonance ( 1 H NMR), and scanning electron microscopy (SEM) were performed to characterize the graft-copolymer. The rheological properties of the graft-copolymer were investigated at different salinities and temperatures. The graft-copolymer solution showed better salt resistance, temperature tolerance, and long-term thermal stability than partially hydrolyzed polyacrylamide (HPAM). In addition, hydrogels were prepared using the graft-copolymer with varying M w (346 × 10 4 –1319 × 10 4 ), a crosslinker (hexamethylenetetramine–resorcinol, (HMTA–RC)), and additives (citric acid, (CA), and ammonium phosphate monobasic, (MAP)), and the hydrogels exhibited adequate strength and tunable gelation time. The hydrogels prepared using the graft-copolymer with high M w possessed excellent long-term stabilities with negligible syneresis at 45 °C after 130 d, for the same conditions, the syneresis of conventional hydrogels prepared by HPAM reached approximately 90%.
研究领域:
聚合物化学
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材料科学
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石油工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF DISPERSION SCIENCE AND TECHNOLOGY
·
2021
·
IF 2.262
Li Chao,Haiwang Wang,Xinfang Wei,Jinlong Li,Cheng Ji,Xiwei Qi
At present, the polymer flocculation technology has been widely used in the treatment of oil sand tailings. However, the current composite flocculant still has the problems of low flocculation efficiency and serious secondary pollution after using. In this article, cationic composite flocculant SiO2-TiO2-P(AM-DMC) with self-degrading characteristics was prepared by the surface photoinitiated polymerization technique. Above all, in order to study the synthesis process of SiO2-TiO2-P(AM-DMC), cationic composite flocculant was characterized by FTIR, TG, TEM, XPS, etc. Furthermore, the central composite design (CCD) and response surface methodology (RSM) were used to optimize the preparation parameters of the cationic composite flocculant. And the optimization results of preparation parameters of cationic composite flocculant showed that the optimal preparation parameters of SiO2-TiO2-P(AM-DMC) were as follows: mDMC: mAM = 5, monomer concentration was 35% and reaction time was 100 min. Ultimately, the flocculation parameters of SiO2-TiO2-P(AM-DMC) were optimized by CCD and RSM. Moreover, the optimization results of flocculation parameters of cationic composite flocculant showed that the optimal flocculation parameters of SiO2-TiO2-P(AM-DMC) were as follows: pH = 5, flocculant dosage was 30 ppm, kaolin concentration was 1.36%. In summary, this work had greatly enriched the knowledge of oil sand tailings treatment, and had the extremely important reference significance for realizing the parameter regulation of high-efficiency flocculation of oil sand tailings.
研究领域:
环境科学
·
材料科学
·
化学工程
✓ 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）