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1.
Carbohydr Polym ; 335: 122067, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38616090

RESUMO

Inspired by creatures, abundant stimulus-responsive hydrogel actuators with diverse functionalities have been manufactured for applications in soft robotics. However, constructing a shape memory and self-sensing bilayer hydrogel actuator with high mechanical strength and strong interfacial bonding still remains a challenge. Herein, a novel bilayer hydrogel with a stimulus-responsive TEMPO-oxidized cellulose nanofibers/poly(N-isopropylacrylamide) (TOCN/PNIPAM) layer and a non-responsive TOCN/polyacrylamide (TOCN/PAM) layer is proposed as a thermosensitive actuator. TOCNs as a nano-reinforced phase provide a high mechanical strength and endow the hydrogel actuator with a strong interfacial bonding. Due to the incorporation of TOCNs, the TOCN/PNIPAM hydrogel exhibits a high compressive strength (~89.2 kPa), elongation at break (~170.7 %) and tensile strength (~24.0 kPa). The prepared PNIPAM/TOCN/PAM hydrogel actuator performs the roles of an encapsulation, jack, temperature-controlled fluid valve and temperature-control manipulator. The incorporation of Fe3+ further endows the bilayer hydrogel actuator with a synergistic performance of shape memory and temperature-driven, which can be used as a temperature-responsive switch to detect ambient temperature. The PNIPAM/TOCN/PAM-Fe3+ conductive hydrogel can be assembled into a flexible sensor and generate sensing signals when driven by temperature changes to achieve real-time feedback. This research may lead to new insights into the design and manufacturing of intelligent flexible soft robots.

2.
Sci Total Environ ; 925: 171756, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38494013

RESUMO

The degradation of biodegradable plastics (BPs) in natural environments is constrained, and the mechanisms underlying their photoaging in aquatic settings remain inadequately understood. In view of this, this study systematically investigated the photoaging process of biodegradable Poly (butyleneadipate-co-terephthalate) microplastics (PBAT-MPs), which are more widely used. The investigation was carried out in the presence of common inorganic anions (Br-, Cl- and NO3-). The results of EPR, FTIR and FESEM tests, along with pseudo-first-order kinetics analyses, showed that the presence of NO3- promoted the photoaging of PBAT-MPs, while the presence of Br- and Cl- inhibited the photoaging of PBAT-MPs. In addition, the results of the Two-Dimensional Correlation Spectroscopy (2D-COS) analysis determined the order of the changes in the functional groups, revealing that the Norrish I and Norrish II reaction mechanisms are presented by PBAT-MPs during the aging process, and the process is closely related to the ion concentration and UV irradiation time. This study provides valuable insights for understanding the phototransformation process of BPs in natural aqueous environments.

3.
Carbohydr Polym ; 333: 121947, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38494214

RESUMO

The rapid development of hydrogels has garnered significant attention in health monitoring and human motion sensing. However, the synthesis of multifunctional conductive hydrogels with excellent strain/pressure sensing and photoresponsiveness remains a challenge. Herein, the conductive hydrogels (BPTP) with excellent mechanical properties, fatigue resistance and photoresponsive behavior composed of polyacrylamide (PAM) matrix, 2,2,6,6-tetramethylpiperidin-1-yloxy-oxidized cellulose nanofibers (TOCNs) reinforcement and polydopamine-modified black phosphorus (BP@PDA) photosensitizer are prepared through a facile free-radical polymerization approach. The PDA adhered to the BP surface by π-π stacking promotes the optical properties of BP while also preventing BP oxidation from water. Through hydrogen bonding interactions, TOCNs improve the homogeneous dispersion of BP@PDA nanosheets and the mechanical toughness of BPTP. Benefiting from the synergistic effect of PDA and TOCNs, the conductive BPTP integrates superior mechanical performances, excellent photoelectric response and photothermal conversion capability. The BPTP-based sensor with high cycling stability demonstrates superior strain sensitivity (GF = 6.0) and pressure sensing capability (S = 0.13 kPa-1) to monitor various human activities. Therefore, this work delivers an alternative construction strategy for generating high-performance conductive hydrogels as multifunctional wearable sensors.


Assuntos
Celulose Oxidada , Dispositivos Eletrônicos Vestíveis , Humanos , Condutividade Elétrica , Hidrogéis , Ligação de Hidrogênio
4.
Carbohydr Polym ; 299: 120119, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36876770

RESUMO

Membranes for water remediation require structural stability, efficient operation, and durability. In this work, we used cellulose nanocrystals (CNC) to reinforce hierarchical nanofibrous membranes based on polyacrylonitrile (PAN). Hydrolysis of the electrospun nanofibers (H-PAN) enabled hydrogen bonding with CNC and provided reactive sites for grafting cationic polyethyleneimine (PEI). In a further modification, anionic silica particles (SiO2) were adsorbed on the fiber surfaces, obtaining CNC/H-PAN/PEI/SiO2 hybrid membranes, which developed swelling resistance (swelling ratio of 6.7 compared to 25.4 measured for a CNC/PAN membrane). Hence, the introduced hydrophilic membranes contain highly interconnected channels, they are non-swellable and exhibit mechanical and structural integrity. By contrast with untreated PAN membranes, those obtained after modification displayed high structural integrity and allowed regeneration and cyclic operation. Finally, wettability and oil-in-water emulsion separation tests demonstrated remarkable oil rejection and separation efficiency in aqueous media.

5.
Carbohydr Polym ; 296: 119891, 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-36087966

RESUMO

Stretchable electroluminescent (EL) devices show great potential for wearable displays. However, the integration of stretchability, flexibility, temperature-tolerance, waterproofness and biocompatibility into a single EL device remains a challenge. Herein, we report a facile full solution-process method for a novel EL device consisting of a dielectric luminescent layer sandwiched between two silver nanowires-cellulose nanocrystals with II crystalline allomorphs/polydopamine-polydimethylsiloxane (CNC II-AgNWs/PDA-PDMS) electrodes. CNC II is used as a green dispersant, film-forming agent and antioxidant to improve the optical, electrical, mechanical and antioxidant properties of the electrodes. The electrodes exhibit a smooth surface, low sheet resistance (~11 Ω sq-1), high transparency (~79.2 %), ideal stretchability (~100 % strain) and excellent inoxidizability. The assembled EL devices with outstanding tensile stability and fatigue resistance demonstrate excellent luminance, flexibility and stretchability underwater and at extreme temperatures, as well as intrinsic biocompatibility. Our multifunctional EL devices with outstanding integrated properties provide new insights for the next-generation flexible electronics.


Assuntos
Nanofios , Antioxidantes , Eletrodos , Eletrônica , Nanofios/química , Prata
6.
ACS Appl Mater Interfaces ; 14(30): 35040-35052, 2022 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-35861436

RESUMO

Nanocellulose-mediated MXene composites have attracted widespread attention in the fields of sustainable energy, wearable sensors, and electromagnetic interference (EMI) shielding. However, the effects of different nanocelluloses on the multifunctional properties of nanocellulose/Ti3C2Tx composites still need further exploration. Herein, we use three types of nanocelluloses, including bacterial cellulose (BC), cellulose nanocrystals (CNCs), and 2,2,6,6-tetramethylpiperidin-1-yloxy (TEMPO)-oxidized cellulose nanofibers (TOCNs), as intercalation to link Ti3C2Tx nanosheets via a self-assembly process, improving the dispersibility, film-forming ability, mechanical properties, and multifunctional performances of nanocelluloses/Ti3C2Tx hybrids through electrostatic forces and hydrogen bonding. The optimized ultrathin (∼40 µm) TOCN/Ti3C2Tx film integrates excellent tensile strength (∼98.89 MPa), long-term stability (during deformation and water erosion), favorable photoelectric response (photosensitivity up to 2620%), and temperature response (reaching 163 °C in only 12 s). Laser-cutting patterned TOCN/Ti3C2Tx films are assembled into flexible multifunctional electronics, exhibiting splendid photoresponse performances and tunable electromagnetic energy shielding capability (>96.4%) related to the variation of water content at the film-gel electrolyte interface. Multifunctional patterned devices based on TOCN/Ti3C2Tx composite films provide a novel pathway to rationally design wearable EMI devices with photoelectric response and photothermal conversion.

7.
ACS Appl Mater Interfaces ; 14(21): 24708-24719, 2022 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-35594189

RESUMO

A nanofiltration (NF) membrane containing a NaOH-treated electrospun polyacrylonitrile (HPAN) substrate, an interfacial polymerization (IP) polyamide (PA) layer, a chitosan (CS) coating layer, and an Ag/AgBr/AgVO3 photocatalyst loading layer was prepared. The structural evolution of the membranes was investigated, and their performance was estimated in accordance with the water flux and rejection rate. A probable mechanism for the photocatalytic activity of Ag/AgBr/AgVO3 was proposed. The loading of the Ag/AgBr/AgVO3 heterojunction on the HPAN/PA/CS NF membrane endowed the membrane with excellent self-cleaning properties owing to the photolytic degradation of the dye. The filtration and degradation processes of the Ag/AgBr/AgVO3-loaded membrane constantly promoted each other, and the treatment efficiency achieved with the integrated (filtration + degradation) process was superior to those obtained with the filtration and degradation processes alone. The Ag/AgBr/AgVO3-NF membrane exhibited excellent recyclability and stability when subjected to five integrated filtration-degradation processes. In addition, the Ag/AgBr/AgVO3-NF membrane exhibited an elastic modulus of 65.75 MPa and a toughness of 38.9 kJ/m3 along with a good disinfection effect on Escherichia coli in visible light. The as-prepared photocatalyst-loaded NF membrane with excellent antifouling performance, antimicrobial activity, high strength, and recyclability showed potential for continuous water purification operation.

8.
Carbohydr Polym ; 282: 119049, 2022 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-35123732

RESUMO

The cellulose nanocrystals (CNC) has attracted widespread attention in reinforced materials. However, the application of CNC in electrospinning has been limited due to its self-polymerization. Herein, a cobweb-like nanofibrous membrane was fabricated by electrospinning the polyacrylonitrile (PAN) and sulfydryl-functionalized CNC (SC). The SC content could reach to 48 wt% after the thiolation modification. The membrane with ultrafine fibers and interlaced nets possessed outstanding porosity (91.7%) and underwater superoleophobicity. An ultrahigh permeation flux of 1244 L·m-2·h-1 with a separation efficiency of >99.9% was achieved driven by gravity. The mechanical properties also enhanced significantly with the increase of SC. When the addition amount of SC was 48 wt%, the maximum tensile stress was 2.9 MPa, which was 3.4 times than that of the PAN membrane. The antifouling performance and chemical stability endowed the SC(48)/PAN membrane with intriguing reusability, thus making it exhibit enormous potential in oil/water separation.

9.
ACS Appl Mater Interfaces ; 13(49): 59142-59153, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34851617

RESUMO

With the rapid development of soft electronics, flexible and stretchable strain sensors are highly desirable. However, coupling of high sensitivity and stretchability in a single strain sensor remains a challenge. Herein, a kind of conductive elastomer is constructed with poly(dimethylsiloxane) (PDMS) and silylated cellulose nanocrystal (SCNC)/carbon nanotube (CNT) nanohybrids through a facile one-pot solution-casting method. The hydrophobic SCNCs can effectively facilitate the dispersion of CNTs in PDMS and synergistically improve the interfacial compatibility between CNTs and the PDMS matrix, resulting in favorable stress and electron transfer in the polymer network. Due to the outstanding electrical conductivity of CNTs and the excellent dispersity and high mechanical performance of SCNCs, combined with the good compatibility between SCNC-mediated carbon nanotubes (SCNC-CNTs) and PDMS, the resulting composite elastomer (SCNC-CNT/PDMS) shows high electrical conductivity (∼2.77 S m-1), tensile strength (∼5.72 MPa), and fatigue resistance properties. The strain sensor assembled by SCNC-CNT/PDMS demonstrates a high strain range above 100%, appealing strain sensitivity with a gauge factor of 37.11 at 50-100% strain, and long-term stability and durability, which is capable of monitoring both real-time human motions and acoustic vibrations. This work paves a new way for the design and controllable preparation of flexible and stretchable conductive elastomers, demonstrating promising applications in wearable devices and intelligent electronics.

10.
ACS Appl Mater Interfaces ; 13(42): 50281-50297, 2021 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-34637615

RESUMO

Flexible sensors have attracted great research interest due to their applications in artificial intelligence, wearable electronics, and personal health management. However, due to the inherent brittleness of common hydrogels, preparing a hydrogel-based sensor integrated with excellent flexibility, self-recovery, and antifatigue properties still remains a challenge to date. In this study, a type of physically and chemically dual-cross-linked conductive hydrogels based on 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO)-oxidized cellulose nanofiber (TOCN)-carrying carbon nanotubes (CNTs) and polyacrylamide (PAAM) matrix via a facial one-pot free-radical polymerization is developed for multifunctional wearable sensing application. Inside the hierarchical gel network, TOCNs not only serve as the nanoreinforcement with a toughening effect but also efficiently assist the homogeneous distribution of CNTs in the hydrogel matrix. The optimized TOCN-CNT/PAAM hydrogel integrates high compressive (∼2.55 MPa at 60% strain) and tensile (∼0.15 MPa) strength, excellent intrinsic self-recovery property (recovery efficiency >92%), and antifatigue capacity under both cyclic stretching and pressing. The multifunctional sensors assembled by the hydrogel exhibit both high strain sensitivity (gauge factor ≈11.8 at 100-200% strain) and good pressure sensing ability over a large pressure range (0-140 kPa), which can effectively detect the subtle and large-scale human motions through repeatable and stable electrical signals even after 100 loading-unloading cycles. The comprehensive performance of the TOCN-CNT/PAAM hydrogel-based sensor is superior to those of most gel-based sensors previously reported, indicating its potential applications in multifunctional sensing devices for healthcare systems and human motion monitoring.


Assuntos
Materiais Biocompatíveis/química , Celulose/química , Hidrogéis/química , Nanotubos de Carbono/química , Dispositivos Eletrônicos Vestíveis , Resinas Acrílicas/química , Materiais Biocompatíveis/síntese química , Condutividade Elétrica , Humanos , Teste de Materiais
11.
Bioorg Chem ; 114: 105103, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34174630

RESUMO

Fluorescence probe combines with fluorescence imaging technology has become the most powerful analytical method with their great advantages of high sensitivity and selectivity and real-time monitoring. Ni2+ is widely distributed in food, environment and living animals, thereof, it is of great significance for detection Ni2+ with high selectivity. Herein, a simple strategy is proposed to design and synthesiz a small molecule fluorescent probe Y1 by using "one-pot" method. The spectroscopic behaviors including UV-Vis absorption and fluorescence emission spectrum have been used to verify the feasibility of probe towards Ni2+ in water/EtOH (v/v = 2:8) mixtures under neutral condition. As expected, Y1 offers high selectivity and sensitivity for detection Ni2+ in aqueous solution with a good linear relationship and low detection limit within Ni2+ concentration variation from 0 to 13 µM (DOL = 0.0038 µM, R2 = 0.9983). It is remarkable that Y1 can be applied for real-time visualization Ni2+ change in sprouted potato and zebrafish with great photo-stability, highlighting that the practicability and feasibility of Y1 to detect and monitor Ni2+ in the field of food industry and biomedical field.


Assuntos
Colorimetria , Corantes Fluorescentes/química , Níquel/análise , Solanum tuberosum/química , Animais , Espectrometria de Fluorescência , Espectrofotometria Ultravioleta , Raios Ultravioleta , Peixe-Zebra
12.
J Colloid Interface Sci ; 597: 171-181, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33866209

RESUMO

HYPOTHESIS: Hydrogel-based sensors have attracted considerable attention due to potential opportunities in human health monitoring when both mechanical flexibility and sensing ability are required. Therefore, the integration of excellent mechanical properties, electrical conductivity and self-healing properties into hydrogels may improve the application range and durability of hydrogel-based sensors. EXPERIMENTS: A novel composite hydrogel composed of polyaniline (PANI), polyacrylic acid (PAA) and 2,2,6,6-tetramethylpiperidin-1-yl)oxyl (TEMPO)-oxidized cellulose nanofibrils (TOCNFs) was designed. The viscoelastic, mechanical, conductive, self-healing and sensing properties of hydrogels were studied. FINDINGS: The TOCNF/PANI/PAA hydrogel exhibits a fracture strain of 982%, tensile strength of 74.98 kPa and electrical conductivity of 3.95 S m-1, as well as good mechanical and electrical self-healing properties within 6 h at ambient temperature without applying any stimuli. Furthermore, owing to the high sensitivity of the TOCNF/PANI/PAA-0.6 hydrogel-based strain sensor (gauge factor, GF = 8.0), the sensor can accurately and rapidly detect large-scale motion and subtle localized activity. The proposed composite hydrogel is as a promising material for use as soft wearable sensors for health monitoring and smart robotics applications.

13.
Int J Biol Macromol ; 172: 330-340, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33453256

RESUMO

Novel nanocomposite hydrogels were successfully prepared by blending and crosslinking sodium alginate (SA), poly(vinyl alcohol) (PVA) and cellulose nanofibers (CNFs) in the presence of a fertilizer formulation containing nitrogen (N), phosphorus (P) and potassium (K). The hydrogels had a macroporous flexible core and a microporous semi- interpenetrating polymer network (IPN) shell. The crystalline nature of the NPK chemicals was retained in the hydrogel nanocomposite network. Furthermore, the SA/CNF/PVA-based hydrogels showed a higher water-retention capacity in both deionized water and mixed soil. The swelling behavior in various physiological pH, salt and alkali solutions exhibited good sensitivity. The NPK release from SA/CNF/NPK and SA/CNF/PVA/NPK hydrogels was controlled by Fickian diffusion in both water and soil based on the Korsmeyer-Peppas release kinetics model (n < 0.5). Therefore, the prepared hydrogels have the potential for applications in drought-prone and/or fertilizer-loss regions for future development of precision agriculture and horticulture.


Assuntos
Alginatos/química , Preparações de Ação Retardada/química , Nanofibras/química , Nitrogênio/química , Fósforo/química , Álcool de Polivinil/química , Potássio/química , Agricultura/métodos , Cristalização , Liberação Controlada de Fármacos , Fertilizantes/análise , Humanos , Concentração de Íons de Hidrogênio , Cinética , Nanofibras/ultraestrutura , Porosidade , Água/química
14.
J Hazard Mater ; 401: 123798, 2021 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-33113738

RESUMO

Novel portable, high-precision, and reusable fluorescent polyvinyl alcohol (PVA)-borax hydrogel sensors were prepared to detect Cu2+ in aqueous environment. A TEMPO-oxidized cellulose nanofibers/salicylaldehyde thiosemicarbazone (TOCN/ST) complex was further incorporated into the PVA-borax matrix. The in situ polymerization of TOCN/ST complex enhanced the mechanical properties of the hydrogels and improved the accuracy of detection. The resultant hydrogels were thermo reversible, and it converted to the liquid state during heating, which could greatly reduce the deviations caused in the detection of solid sensors. After cooling, the hydrogel could transform into the solid condition, which was easily portable. The sensor induced a significant luminescence quenching to the Cu2+ at 485 nm, with a detection limit of 0.086 µM. In the presence of ethylenediaminetetraacetic acid disodium, Cu2+ were tightly seized, causing the liberation of TOCN/ST complex and thus, a reversible "ON-OFF-ON" fluorescence behavior was displayed. The fluorescence intensity was maintained at 82 % after 10 uses, and the mechanical strength was maintained at 85 % after 3 uses. The anti-bacterial activity test also confirmed the TOCN/ST complex was extremely potent in suppressing the growth and reproduction of Escherichia coli. The proposed hydrogel provides a new insight into the detection of Cu2+ in aqueous environments.


Assuntos
Celulose , Álcool de Polivinil , Aldeídos , Hidrogéis , Luminescência , Tiossemicarbazonas
15.
Carbohydr Polym ; 250: 116905, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-33049881

RESUMO

Stretchable, self-healing and conductive hydrogels have attracted much attention for wearable strain sensors, which are highly required in health monitoring, human-machine interaction and robotics. However, the integration of high stretchability, self-healing capacity and enhanced mechanical performance into one single conductive hydrogel is still challenging. In this work, a type of stretchable, self-healing and conductive composite hydrogels are fabricated by uniformly dispersing TEMPO-oxidized cellulose nanofibers (TOCNFs)-graphene (GN) nanocomposites into polyacrylic acid (PAA) hydrogel through an in-situ free radical polymerization. The resulting hydrogels demonstrate a stretchability (∼850 %), viscoelasticity (storage modulus of 32 kPa), mechanical strength (compression strength of 2.54 MPa, tensile strength of 0.32 MPa), electrical conductivity (∼ 2.5 S m-1) and healing efficiency of 96.7 % within 12 h. The hydrogel-based strain sensor shows a high sensitivity with a gauge factor of 5.8, showing great potential in the field of self-healing wearable electronics.


Assuntos
Condutividade Elétrica , Grafite/química , Hidrogéis/química , Monitorização Fisiológica/instrumentação , Movimento , Nanocompostos/química , Dispositivos Eletrônicos Vestíveis , Materiais Biocompatíveis/química , Humanos , Monitorização Fisiológica/métodos
16.
Nanomaterials (Basel) ; 10(1)2020 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-31935929

RESUMO

Recently, with the development of personal wearable electronic devices, the demand for portable power is miniaturization and flexibility. Electro-conductive hydrogels (ECHs) are considered to have great application prospects in portable energy-storage devices. However, the synergistic properties of self-healability, viscoelasticity, and ideal electrochemistry are key problems. Herein, a novel ECH was synthesized by combining polyvinyl alcohol-borax (PVA) hydrogel matrix and 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO)-cellulose nanofibers (TOCNFs), carbon nanotubes (CNTs), and polyaniline (PANI). Among them, CNTs provided excellent electrical conductivity; TOCNFs acted as a dispersant to help CNTs form a stable suspension; PANI enhanced electrochemical performance by forming a "core-shell" structural composite. The freeze-standing composite hydrogel with a hierarchical 3D-network structure possessed the compression stress (~152 kPa) and storage modulus (~18.2 kPa). The composite hydrogel also possessed low density (~1.2 g cm-3), high water-content (~95%), excellent flexibility, self-healing capability, electrical conductivity (15.3 S m-1), and specific capacitance of 226.8 F g-1 at 0.4 A g-1. The fabricated solid-state all-in-one supercapacitor device remained capacitance retention (~90%) after 10 cutting/healing cycles and capacitance retention (~85%) after 1000 bending cycles. The novel ECH had potential applications in advanced personalized wearable electronic devices.

17.
J Colloid Interface Sci ; 564: 99-112, 2020 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-31911232

RESUMO

A novel photocatalytic hydrogel was prepared by loading TiO2 nanoparticles (TiO2 NPs) onto the surface of 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO)-oxidized chitin nanofibers (TOCNs), which were further incorporated into the polyacrylamide (PAM) matrix. The resultant hydrogel exhibited a macro-porous structure with a low density (~1.45 g/cm3) and high water content (~80%). The well-dispersed TiO2 NPs not only acted as a crosslinking agent for bridging the three-dimensional porous network structure, but also endowed the hydrogel with good catalytic activity. After the introduction of TiO2 accounting for 10 wt% of the hydrogel mass, the hydrogels showed compressive strength of 1.46 MPa at 70% strain, tensile stress of 316 kPa, tensile strain of 310%, toughness of 47.25 kJ/m3 and fatigue resistance. Compared with neat TOCN-PAM hydrogel, the uniaxial compressive and tensile strengths of the TiO2-TOCN-PAM10 hydrogel increased 6.35-fold and 3.70-fold, respectively. Furthermore, the removal of methyl orange (MO) was attributed to the synergistic effect of the adsorption and photocatalytic degradation of the hydrogels. The hydrogels adsorbed up to 8.5% of MO after 150 min of adsorption and a photocatalytic degradation rate of 97.3% achieved after 90 min of UV irradiation at pH = 2. Especially, the TiO2-TOCN-PAM10 hydrogel exhibited excellent recycling performance: its MO removal efficiency was around 96% even after 10 reuse cycles. The as-prepared hydrogels, with characteristics of excellent stretchability, photocatalytic activity and recyclability, are expected to be used in alleviating organic pollutants in practical wastewater treatments.

18.
Strabismus ; 28(1): 29-33, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31847669

RESUMO

Purpose: Monocular transposition of the inferior oblique muscle belly (IOMBT) effectively weakened mild to moderate inferior oblique overaction and corrected small primary position hypertropia. Now we aim to evaluate the efficacy of inferior oblique muscle belly transposition (IOMBT) in treating V pattern strabismus with upshoot in adduction.Methods: This is a retrospective review of 13 patients with V pattern who underwent IOMBT procedure from January 2017 to December 2018. The inclusion criteria were: the amount of V pattern from 15 to 25 pd; the degree of upshoot in adduction from +1 to +3; no or trace vertical deviation in primary gaze position. Bilateral IOMBT was performed to reduce the V pattern. Horizontal rectus muscle surgery was performed at the same stage to correct the horizontal deviation. The angle of deviation in upgaze and downgaze was measured pre- and postoperatively. The degree of elevation in adduction was graded. The amount of V pattern was the difference in horizontal angle between up- and downgaze. The change in the amount of V pattern was assessed postoperatively.Results: All 13 patients had complete resolution of the V pattern. The amount of V pattern changed from 18.92 ± 4.310 prism diopters to 3.462 ± 1.854 prism diopters postoperatively. The mean grade of upshoot in adduction changed from 1.92 to 0.12 postoperatively. No depression in adduction or consecutive A pattern were found after surgery.Conclusions: IOMBT can successfully eliminate the V pattern in patients with mild V pattern esotropia or exotropia with mild to moderate upshoot in adduction. This procedure appears to be a useful addition to our inferior oblique surgical armamentarium.


Assuntos
Músculos Oculomotores/transplante , Procedimentos Cirúrgicos Oftalmológicos/métodos , Estrabismo/cirurgia , Adolescente , Adulto , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Período Pós-Operatório , Estudos Retrospectivos , Estrabismo/fisiopatologia , Resultado do Tratamento , Visão Binocular/fisiologia
19.
Strabismus ; 28(1): 25-28, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31775558

RESUMO

Purpose: To evaluate the efficacy of single or combined superior oblique tendon (SO) advancement for selected cases of unilateral superior oblique palsy (SOP).Methods: The medical records of 14 patients who underwent single or combined superior oblique tendon advancement in one institution from May 2017 to October 2018 were reviewed. All subjects with a diagnosis of unilateral SOP who underwent single or combined SO tendon advancement surgery were included. The goal of the surgery was to correct the hypertropia and head tilt. The single or combined SO tendon advancement surgery was selected based on the amount of hypertropia or head tilt and the Knapp classification of the SOP. The information recorded included pre- and postoperative deviation angle and ocular motility findings. The degree of upshoot in adduction was graded pre- and postoperatively.Results: Fourteen patients between the age of 3 and 52 years with unilateral superior oblique palsy were selected to undergo SO tendon advancement. Single SO tendon advancement was carried out in eight acquired Knapp class II or residual SOP patients. SO tendon advancement combined with contralateral inferior rectus recession was carried out in two acquired Knapp class II patients. SO tendon advancement combined with ipsilateral inferior oblique myectomy was carried out in four congenital Knapp class III patients. The changes in pre- and postoperative hypertropia at primary gaze in single SO tendon advancement patients were from 6.25 ± 2.12 prism diopters to 0.86 ± 1.46 prism diopters. The changes in degree of upshoot in adduction were from +1.86 to +0.21. Conclusions: SO tendon advancement worked well as single or combined muscle procedure to treat unilateral superior oblique palsy.


Assuntos
Músculos Oculomotores/cirurgia , Estrabismo/cirurgia , Tendões/cirurgia , Doenças do Nervo Troclear/cirurgia , Adolescente , Adulto , Criança , Pré-Escolar , Progressão da Doença , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Oftalmológicos/métodos , Período Pós-Operatório , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
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