查找使用阿拉丁产品的科研文献

Development of high refractive and high water content polythiourethane/AA hydrogels for potential artificial cornea implants

Youlan Zeng,Lu Fan,Min Deng,Peng Sun,Boxiao Zhang,Quanyuan Zhang,Ling Li,Zushun Xu

Synthesis and evaluation of an environment-friendly terpolymer CaCO3 scale inhibitor for oilfield produced water with better salt and temperature resistance

Kaixiang Cui,Chuanxian Li,Bo Yao,Fei Yang,Guangyu Sun

The CaCO 3 deposits exist widely in the petroleum industry, causing severe damage to the equipment and production. In this article, a novel environment-friendly terpolymer scale inhibitor Poly (maleic anhydride - acrylic acid -2- acrylamide -2- methyl propanesulfonic acid) (P(MA-AA-AMPS))-containing carboxylic acid group, sulfonic acid group, and amide group was synthesized. The structure and molecular weight were characterized by FTIR, 1 H-NMR, and GPC. The static scale inhibition experiment was conducted to study the influence of factors such as the dosage, monomer ratio, temperature, pH, Ca 2+ concentration, and concentration on the scale inhibition performance of CaCO 3 . The results show that when the monomer ratio is 2.0:1.0:0.5 and the dosage is 20 mg L −1 , the maximum scale inhibition efficiency is 95.52%. Even when Ca 2+ concentration exceeds 1200 mg L −1 and temperature reaches 90 °C, the scale inhibition efficiency is still larger than 80%. The results of SEM and XRD show that P(MA-AA-AMPS) interferes with the growth of CaCO 3 crystal by adsorption, dispersion, and chelation. The effect leads to changes in the morphology of CaCO 3 crystals, the size of which drops from 20–30 μm to 2–5 μm. The P(MA-AA-AMPS) can transform CaCO 3 from stable calcite crystals to unstable aragonite and vaterite. Finally, the formation of CaCO 3 scale is well inhibited. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137 , 48460.

AA/MA/AMA copolymer and chitosan as self-gelling powders for rapid hemostasis and robust tissue adhesion

Wan Peng,Yefeng Jiang,Yang Zhang,Youjin Lai,Yiming Zhu,Huixia Wang,Zilin Kan,Pingsheng Liu

Bleeding control by traditional hemostatic materials poses a risk of continuing oozing bleeding, while existing self-gelling hemostatic powders still face challenges in simultaneously achieving robust wound sealing and effectively accelerating blood coagulation. Herein, we reported acrylic acid/methacrylic acid/2-aminoethyl methacrylate copolymer (PAMA) and chitosan (CS) as a new type of self-gelling composite powder (PAMA-CS) for acute bleeding wound sealing with reduced blood leakage. Upon rapid blood absorption, PAMA-CS powders could quickly form an adhesive hydrogel that strongly binds to bleeding tissues, exhibiting high burst pressure tolerance (up to 452.6 mmHg) for wound sealing to prevent bleeding. The incorporation of chitosan endowed significantly enhanced liquid uptake ability and accelerated blood coagulation (clot index of 77.92 % within 30 s) to the PAMA-CS powder. Based on the synergistic effect of tight adhesive sealing and accelerating intrinsic blood coagulation, PAMA-CS powders could achieve effective hemostasis within 20 s for acute bleeding liver and stomach on rats, outperforming commercial hemostatic chitosan powders. Combined with rapid hemostasis, tight & stable wound sealing, and favorable biodegradation, PAMA-CS powders may serve as a promising hemostatic candidate for emergency bleeding control and wound closure.

AA grafted PVA/CMC interpenetrating network gel polymer electrolyte for quasi-solid-state zinc ion hybrid supercapacitor

Yongtao Tan,Mei Xi,Yuan Zhang,Zhengda Qiao

Polymer gel electrolyte is a topic for a storage energy device. This work focuses on the double interpenetrating network polymer of polyvinyl alcohol/carboxymethyl cellulose (PVA/CMC) to graft acrylic acid (AA) and combine ZnCl 2 to form multi-polymer network gel electrolyte for zinc ion supercapacitors. The assembled zinc ion supercapacitors of commercial activated carbon (YP50)//Zn with multi-polymer network gel electrolyte exhibit higher specific capacitance of 272 F g −1 at a current density of 0.25 A g −1 than the device with polyvinyl alcohol/polyacrylic acid (PVA/PAA) or PVA electrolyte. In addition, the zinc ion supercapacitor can achieve a maximum energy density of 151.2 Wh kg −1 , higher than traditional electrical double layer supercapacitor YP50//YP50 device. Further, the device can work under different temperatures from −20∼60 °C, which can meet the requirements of some outdoor activities for energy storage devices.

Biocontrol potential of the active substance isolated from the endophytic fungus Aa-Lcht against apple Valsa canker

Yanting He,Hua Wang,Weimin Ma,Chengyu Gao,Runze Tian,Xiaozhou Su,Hao Feng,Lili Huang

Apple Valsa canker (AVC), primarily caused by the pathogenic fungus Valsa mali , is a devastating disease of apple. The development and application of high efficiency and low toxicity fungicides are of great significance for disease control. Natural active substances serve as a vital foundation for the development of novel green fungicides. In previous studies, the endophytic fungus Aa-Lcht was confirmed to contain specific inhibitory effect against V. mali . This study confirmed that Aa-Lcht fermentation broth (FB)’s suppression of V. mali growth and conidial germination, exhibiting AVC prevention. Through extraction, isolation, and purification, one active substance with high inhibitory effect on V. mali was obtained and identified as altenusin. Its concentration value for 50 % of maximal effect (EC 50 values) against V. mali mycelium growth was 3.118 μg/mL. Before V. mali infection, the lesion length of apple twigs and lesion area of fruits pretreated with altenusin decreased by 47.27 % and 80.52 %, respectively. Further research revealed that the hyphae of V. mali treated with altenusin exhibited irregular thickening of cell walls, severe vacuolation within the cells, and protoplasmic exudation. Meanwhile, transcriptome analysis indicated that altenusin primarily inhibited V. mali by interfering with the normal hyphal cell metabolism, substance degradation, peptidase activity, and proteolysis functions. Additionally, altenusin could also significantly up-regulate the expression of immunity resistance-related genes MdCYP81F2 , MdPR2 , MdPR4 , and MdPR5 in apple. Summarizing the above, the altenusin provides valuable insights for the development of novel green fungicides for controlling AVC disease, contributing to the safe and healthy development of apple production.

Dual-Responsive Graphene Oxide/Poly(NIPAM-co-AA) Hydrogel as an Adsorbent for Rhodamine B and Imidacloprid

Guohong Yao,Sisi Li,Jun Xu,Hui Liu

A dual-responsive hydrogel based on graphene oxide (GO) was prepared by in situ radical copolymerization of N-isopropyl acrylamide (NIPAM) as a temperature-sensitive component and acrylic acid (AA) as a pH-sensitive unit. The resulting hydrogels (GO/poly(NIPAM-co-AA) (PNA) were systematically characterized by Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, Raman spectroscopy, thermogravimetric analysis, differential scanning calorimetry, and scanning electron microscopy. With the change of AA content, the lower critical solution temperature of hydrogels changed from 26.91 to 24.38 °C. The swelling ratio under alkaline condition was higher than that under acidic condition. The adsorption of rhodamine B (RB) followed Langmuir isotherm model and pseudo-second-order model, and nearly 93% of RB could be released within 10 h at pH 4.01 and 60 °C. With imidacloprid as the model drug, the higher cumulative release rate of the GO/PNA hydrogel was obviously observed at pH = 4.01 than at pH = 9.18. On the basis of their good adsorption–desorption, loading-releasing, and regeneration ability, the GO/PNA hydrogel as a multifunctional adsorbent might have broad application prospects in environmental protection and biomedical engineering.

Synthesis and characterization of SSS/HAM/AA terpolymer as a fluid loss additive for oil well cement

Jing Wu,Ming Li,Aili Zhang

A terpolymer comprising of sodium styrene sulfonate (SSS), n -methylol acrylamide (HAM), and acrylic acid (AA) was synthesized by aqueous free radical copolymerization and evaluated as fluid loss additive (FLA) in oil well cement. In this article, HAM is first introduced in the preparation of FLA as an environment-friendly monomer, which effectively improves the adhesion and fluid loss control of the terpolymer. The experimental synthesis conditions were optimized by orthogonal experiments. The molecule weight of the terpolymer was determined by gel permeation chromatography. The molecule structure of the synthesized terpolymer was verified by X-ray photoelectron spectroscopy and Fourier transformer infrared spectrum. The thermal stability of the synthesized terpolymer was tested by thermogravimetry (TG). The structure of the terpolymer aqueous solution was observed by scanning electron microscope. The results show that SSS/HAM/AA has an excellent thermal resistant. The thermal degradation is not obvious before 295.2 °C. Furthermore, the microstructure of SSS/HAM/AA in water conducive to good fluid loss control ability. When the dosage of SSS/HAM/AA is up to 2.0% in fresh water cement slurry, the filtration loss [FL (HTHP) ] can be controlled within 50 mL at 90–150 °C. SSS/HAM/AA has an excellent property of reducing filtration loss. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135 , 46266.

Improving the mechanical performance of P(N-hydroxymethyl acrylamide/acrylic acid/2-acrylamido-2-methylpropanesulfonic acid) hydrogel via hydrophobic modified nanosilica

Pan Xu,Yi Zong,Zhijie Shang,Meiling Yao,Pingde Liu,Xinxue Li

Hydrogels with high mechanical strength are essential for its most industrial applications. In this work, the hydrophobic SiO 2 nanoparticles (M-SiO 2 NPs) modified with octadecyltrimethoxysilane were used as physical crosslinker to toughen the mechanical properties of hydrogels. The solution of monomers containing M-SiO 2 NPs, N-hydroxymethyl acrylamide (NHAM), acrylic acid (AA), 2-acrylamido-2-methylpropanesulfonic acid (AMPS), was polymerized to prepare a P(NHAM/AA/AMPS)-based composite hydrogel without any chemical cross-linker. The composition and microstructure of the hydrogel were carefully studied with Fourier transform infrared spectroscopy and scanning electron microscopy. The mechanical properties of the hydrogel were investigated through compressive and tensile tests. Dynamic swelling tests were carried out at different pH values (1.0–12.0) and salinity (2000–20,000 mg/L) to study the acid resistance, alkali resistance, and salt resistance of the hydrogel. The obtained results showed that the hydrogel exhibited excellent mechanical performance, which was attributed to the unique 3D network formed by the hydrogen bond between M-SiO 2 NPs and polymer as well as the hydrophobic association effect between the hydrophobic chains of M-SiO 2 NPs. Furthermore, the hydrophobic association effect was enhanced when contacting with salt, acid, and alkali solutions, thus endowing the hydrogel with intensified salt resistance and wider acid–base adaptability range.

A dual-targeting drug co-delivery system for tumor chemo- and gene combined therapy

Fangrong Zhang,Min Li,Yujie Su,Jianping Zhou,Wei Wang

Regulation of gene expression using p53 is a promising strategy for treatment of numerous cancers, and chemotherapeutic drug dichloroacetate (DCA) induces apoptosis and growth inhibition in tumor, without apparent toxicity in normal tissues. Combining DCA and p53 gene could be an effective way to treat tumors. The progress towards broad applications of DCA/p53 combination requires the development of safe and efficient vectors that target to specific cells. In this study, we developed a DSPE-PEG-AA (1,2-distearoryl- sn -glycero-3-phosphoethanolamine-N-[methoxy(polyethyleneglycol-2000)] ammonium salt-anisamide) modified reconstituted high-density lipoprotein-based DCA/p53-loaded nanoparticles (DSPE-PEG-AA/rHDL/DCA-PEI/p53 complexes), which was fabricated as a drug/gene dual-targeting co-delivery system for potential cancer therapy. Here, DCA-PEI was utilized to effectively condense the p53 plasmid, to incorporate the plasmid into rHDL and to act as an antitumor drug to inhibit tumor cell growth. The DSPE-PEG-AA/rHDL/DCA-PEI/p53 complexes exhibited desirable and homogenous particle size, neutral surface charge and low cytotoxicity for normal cells in vitro . The results of confocal laser scanning microscopy (CLSM) and flow cytometry confirmed that the scavenger receptor class B type I (SR-BI) and sigma receptor mediated dual-targeting function of the complexes inducing efficient cytoplasmic drug delivery and gene transfection in human lung adenocarcinoma cell line A549. And in vivo investigation on nude mice bearing A549 tumor xenografts revealed that DSPE-PEG-AA/rHDL/DCA-PEI/p53 complexes possessed specific tumor targeting and strong antitumor activity. The work described here demonstrated that the DSPE-PEG-AA/rHDL/DCA-PEI/p53 complexes might offer a promising tool for effective cancer therapy.

PH-Responsive PDMS-AA-UA-SiO2@MS Sponge With Switchable Wettability for Efficient and Recyclable Oil-Water Separation

Xinmei Yan,Junjie He,Ying Yang,Hao Jiang,Haipeng Zou,Zichen Zhang,Guanghao Chen,Yan Jiang,Hongwen Zhang

Oily wastewater poses significant threats to environmental ecosystems and human health, and the inherent complexity of oil–water mixtures underscores the urgent need for advanced, intelligent separation materials. In this study, we report the development of a pH-responsive sponge with reversible wettability switching, designed for efficient and adaptive oil–water separation. Acrylic acid-terminated polydimethylsiloxane (PDMS-AA) was synthesized via sodium ethoxide-initiated ring-opening polymerization of octamethylcyclotetrasiloxane (D 4 ), followed by end-capping with acrylic acid. Subsequently, a bifunctional copolymer (PDMS-AA-UA) was prepared through free-radical copolymerization of PDMS-AA and 10-undecenoic acid (UA), which was then grafted onto hydrophilic SiO 2 nanoparticles to form a micro-/nano-structured composite coating. The resulting sponge exhibits reversible, pH-driven wettability transitions. Under acidic (pH 1) and neutral (pH 7) conditions, the surface displays superhydrophobicity with a water contact angle (WCA) of approximately 160°, enabling selective oil absorption. Upon exposure to alkaline conditions (pH 14), deprotonation of carboxyl groups renders the surface hydrophilic, facilitating rapid release of absorbed oil and demonstrating controllable desorption behavior. This switchable wettability enables on-demand separation of various oil–water mixtures.

Phosphotungstic Acid Modulated PNIPAM/P(AA-co-AM) Bilayer Hydrogels With Programmable Thermo-Responsive Kinetics and Enhanced Toughness

Hui Liu,Hongli Jia,Xiaojin Yan,Rouling Chen,Yingying Wang,Kun Chen

en This link goes to a English section zh This link goes to a Chinese section Thermo-responsive hydrogels based on poly(N-isopropylacrylamide) (PNIPAM) are promising candidates for soft actuation, yet their practical applications are often constrained by sluggish thermo-responsive kinetics and insufficient mechanical robustness. Herein, phosphotungstic acid (PTA), a tungsten-containing polyoxometalate, was incorporated to regulate the phase transition behavior and modulate a PNIPAM/P(AA- co -AM) bilayer hydrogel, in which the thermo-responsive PNIPAM layer serves as the actuator whereas the non-thermo-responsive P(AA- co -AM) layer provides mechanical support. By increasing the PTA content up to 4 wt%, the thermally induced deformation time of the PNIPAM layer was prolonged from 30 to 120 s, whereas the recovery time at low temperature was shortened from 120 to 60 min, thereby enabling programmable thermo-responsive kinetics. The thermal transition of the PTA-PNIPAM layer was effectively regulated by PTA, with the lower critical solution temperature (LCST) gradually increasing and tunable up to 42°C, accompanied by an improved thermal stability manifested by reduced mass loss at 150°C. Mechanical characterization demonstrated that the P(AA- co -AM) layer modulated the tensile properties of hydrogel networks, and the bilayer configuration significantly outperformed the pristine PNIPAM hydrogel. Benefiting from the synergistic effects of kinetic regulation and mechanical modulation, the bilayer hydrogel further exhibited multi-substrate adhesion and reversible deformation, enabling an underwater gripping demonstration. This work highlights a polyoxometalate-enabled strategy for simultaneously controlling thermo-responsive kinetics and toughening PNIPAM-based hydrogels, thereby advancing functional soft materials for actuation-related applications. 摘要 en This link goes to a English section zh This link goes to a Chinese section 聚(N-异丙基丙烯酰胺)(PNIPAM)的温敏水凝胶是软体动力领域的有力候选材料,但其迟缓的热响应动力学和有限的机械鲁棒性往往限制了其实际应用。在此,我们在PNIPAM/P(AA- co -AM)双层水凝胶中引入了磷钨酸(PTA),以调控其相变行为并增强材料性能。在该双层结构中,温敏性PNIPAM层作为动力层,而非温敏性P(AA- co -AM)层则提供机械支撑。通过将PTA的含量提高至4 wt%,PNIPAM层的热诱导变形时间从30秒延长至120秒,而在低温下的恢复时间则从120分钟缩短至60分钟,从而实现了可编程的热响应动力学。PTA有效调控了PTA-PNIPAM层的热转变行为,使其低临界溶解温度(LCST)逐渐升高且最高可调至42°C。同时,材料的热稳定性也得到提升,150°C时的质量损失明显减少。力学表征表明,P(AA- co -AM)层调节了水凝胶网络的拉伸性能,且该双层结构的性能显著优于原始PNIPAM水凝胶。得益于动力学调控与机械增韧的协同效应,该双层水凝胶进一步展现出多基底黏附性和可逆变形能力,并成功实现了水下抓取演示。本工作提出了一种基于多金属氧酸盐的水凝胶改性策略,可同时控制PNIPAM基水凝胶的热响应动力学并增强其韧性,从而推动了功能性软材料在相关应用中的发展。

High performance hydrogel sensor based on rGO integrated P(AA-HEMA) and starch for motion and temperature monitoring

Fang Wang,Jiajun Wang,Wen Li,Yimao Wu,Jiaqi Liu

Smart hydrogel materials demonstrated promising application prospects in flexible electronic devices, human-machine interaction systems, and soft robotics owing to their exceptional electrical conductivity. However, significant technical challenges remained to be addressed for developing multifunctional hydrogel systems integrating both sensing and actuation capabilities. In this study, polydopamine (PDA) was employed to conduct in-situ reduction of graphene oxide (GO) under alkaline conditions, yielding reduced graphene oxide (rGO) with superior electrical conductivity and high photothermal conversion efficiency. The resulting nanomaterial was subsequently combined with natural polysaccharide starch to fabricate a poly (acrylic acid-2-hydroxyethyl methacrylate)/starch/reduced graphene oxide (P(AA-HEMA)/St/rGO) hydrogel composite. This hydrogel system exhibited not only exceptional mechanical properties (176 kPa tensile stress and 1258 % strain) and durability, but also demonstrated high conductivity (3.64 S/m) and sensitive sensing characteristics (achieving a gauge factor of 5.15 at 1300 % strain). The developed hydrogel sensor accurately detected various physiological signals including fist clenching, pulse vibration, and vocalization. Furthermore, by leveraging its excellent photothermal response properties, a three-dimensional array sensor configuration was established, enabling real-time monitoring of ambient temperature variations. Through ingenious material design and structural optimization, this research successfully developed a multifunctional smart hydrogel, providing a novel material solution for biomedical applications and flexible electronic devices.