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2.
Zhongguo Zhong Yao Za Zhi ; 46(22): 5825-5831, 2021 Nov.
Artigo em Chinês | MEDLINE | ID: mdl-34951171

RESUMO

This study evaluated the effects of epimedium polysaccharide(EPS) on the solubility of icariin and baohuoside Ⅰ so as to preliminary explore its solubilization function and the underlying mechanism. The solubility of these two insoluble flavonoids in water and polysaccharide solutions was compared by high performance liquid chromatography, and the mechanism was investigated by diffe-rential scanning calorimetry(DSC) and critical micelle concentration determination. The results indicated that their solubilization in crude EPS solutions was concentration-dependent. The solubility of icariin and baohuoside Ⅰ in 20 mg·mL~(-1) EPS-1-1 was 9.05 times and 5.76 times that in water, respectively; while their solubility in 20 mg·mL~(-1) EPS-2-1 was 10.55 and 8.39 times that in water, respectively. The change of the DSC thermograms suggested the formation of new complexes from icariin and baohuoside Ⅰ with polysaccharides. The critical micelle concentrations proved the micellar properties of both EPS-1-1 and EPS-2-1. In short, EPS can significantly increase the solubility of icariin and baohuoside Ⅰ, the mechanism of which may be related to the formation of micellar complexes between EPS and insoluble flavonoids.


Assuntos
Epimedium , Flavonoides , Polissacarídeos , Solubilidade
3.
Transl Vis Sci Technol ; 10(13): 30, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34817575

RESUMO

Purpose: To investigate the effects of indocyanine green (ICG) solution on the viability and cytolysis of human lens epithelial cells ex vivo. Methods: A total of 200 pieces of anterior capsules were obtained during cataract surgery, and 110 pieces of the anterior capsules were randomly divided into five groups and treated by immersion in different concentrations of ICG solution. The remaining 90 anterior capsules were also divided into five groups and treated with a combination of drug immersion and washing in balanced salt solution. Electron microscopy and trypan blue and eosin stains were used to analyze the cells. Percentage of dead, shedding, or living lens epithelial cells was estimated and used to demonstrate effects of the ICG on viability and cytolysis. Results: Compared with the control group, the percentage of dead and shedding lens epithelial cells increased while the percentage of living lens epithelial cells decreased in all the immersion groups. In the washing groups, the percentage of the living lens epithelial cells was 63.42% ± 2.49%, 54.04% ± 1.84%, 43.51% ± 2.63%, 29.21% ± 2.40%, and 15.73% ± 1.61% for the five groups and reflected a concentration-effect relationship. Electron microscopy showed that the higher the concentration of the ICG solution, the more severe the destruction of the lens epithelial cell structure. Conclusions: ICG could reduce the viability of the lens epithelial cells and promote cell cytolysis. Translational Relevance: Our study showed that ICG could directly reduce the viability of the lens epithelial cells in a concentration-dependent fashion, which can theoretically reduce the incidence of posterior capsule opacification.

4.
Inorg Chem ; 60(14): 10738-10748, 2021 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-34212711

RESUMO

The metal/carbon composites prepared by direct pyrolysis of metal-organic frameworks (MOFs) are regarded as ideal catalysts. However, conventional MOFs show a three-dimensional bulk structure. For bulk MOF-derived catalysts, most active metal sites are confined in the interior and not fully utilized. In this work, metal-organic monolayers (MOLs) are used as the starting precursors to prepare carbon-wrapped metal nanoparticles, which are further employed as catalysts for photocatalytic CO2 reduction. The as-prepared Ni-MOLs and Co-MOLs have an ultrathin thickness of ∼1 nm. It is interestingly found that their derived Ni@C and Co@C nanoparticles are highly dispersive and connected with each other like a piece of paper. As compared with bulk MOF-derived counterparts, MOL-derived catalysts increase the accessibility of active metal sites, which can accelerate electron transfer from photosensitizers to Ni@C and Co@C nanoparticles. In this way, the catalytic activity can be greatly improved. Besides, the magnetic nature of Ni@C and Co@C nanoparticles enables the easy separation and recycling of catalysts. It is expected that this work will provide instructive guidelines for the rational design of MOL-derived catalysts.

5.
J Nutr ; 151(7): 1791-1801, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-33982120

RESUMO

BACKGROUND: Selenium (Se) status is closely related to skeletal muscle physiological status. However, its influence on skeletal muscle growth has not been well studied. OBJECTIVES: This study aimed to analyze the impacts of overall Se status (deficient, adequate, and high) on skeletal muscle growth using a growing zebrafish model. METHODS: Zebrafish (1.5-mo-old) were fed graded levels of Se (deficient: 0.10 mg Se/kg; marginally deficient: 0.22 mg Se/kg; adequate: 0.34 mg Se/kg; high: 0.44, 0.57, and 0.69 mg Se/kg) as Se-enriched yeast for 30 d. Zebrafish growth, and Se accumulation, selenoenzyme activity, selenotranscriptome profiles, and oxidative status in the whole body, and selenotranscriptome profiles, histological characteristics, biochemicals, and gene and protein expression profiles related to muscle growth in the skeletal muscle were analyzed by model fitting and/or 1-factor ANOVA. RESULTS: Se status biomarkers within the whole body and skeletal muscle indicated that 0.34 mg Se/kg was adequate for growing zebrafish. For biomarkers related to skeletal muscle growth, compared with 0.34 mg Se/kg, 0.10 mg Se/kg decreased the white muscle cross-sectional area (WMCSA) and the mean diameter of white muscle fibers (MDWMF) by 14.4%-15.1%, inhibited protein kinase B-target of rapamycin complex 1 signaling by 63.7%-68.5%, and stimulated the autophagy-lysosome pathway by 1.07 times and the ubiquitin-proteasome pathway (UPP) by 96.0% (P < 0.05), whereas 0.22 mg Se/kg only decreased the WMCSA by 7.8% (P < 0.05); furthermore, 0.44 mg Se/kg had no clear effects on skeletal muscle biomarkers, whereas 0.57-0.69 mg Se/kg decreased the WMCSA and MDWMF by 6.3%-25.9% and 5.1%-21.3%, respectively, and stimulated the UPP by 2.23 times (P < 0.05). CONCLUSIONS: A level of 0.34 mg Se/kg is adequate for the growth of zebrafish skeletal muscle, whereas ≤0.10 and ≥0.57 mg Se/kg are too low or too high, respectively, for maintaining efficient protein accretion and normal hypertrophic growth.

6.
J Cataract Refract Surg ; 47(12): e66-e69, 2021 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-33929794

RESUMO

Implantation of an intraocular lens (IOL) after combined vitrectomy and cataract surgery is usually required to reduce postoperative refraction errors. However, because of the severe fibrosis of the anterior capsule and the adhesion between the anterior and posterior capsules, it is difficult to reopen the capsular bag to complete the secondary IOL implantation. In this study, a surgical approach is described for reopening the severe adhesion between capsules and removing the significant fibroproliferative membranous material by injecting ophthalmic viscosurgical device into the periphery of the capsular bag to separate the anterior and posterior capsules. The IOL was implanted into the capsular bag without any zonular rupture or posterior capsule tear. The position of the IOL was stable during postoperative follow-up up to 3 months. This procedure to open a severely fibrosis capsule was safe and effective.

7.
ACS Nano ; 15(3): 5355-5365, 2021 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-33631928

RESUMO

Cellulose fiber (CF) paper is a low-cost, sustainable, and flexible substrate, which has gained increasing interest recently. Before practical usage, the functionalization of the pristine CF paper is indispensable to meet requirements of specific applications. Different from conventional surface modification or physical mixing methods, we report in situ growth of ultralong hydroxyapatite nanowires (HAPNWs) with lengths larger than 10 µm on the CF paper. HAPNWs are radially aligned on the surface of CFs, creating a micro/nanoscale hierarchical structure. By means of the excellent ion exchange ability of HAP and the hierarchical structure, the functions of the CF paper can be easily customized. As a proof-of-concept, we demonstrate two kinds of functional CF paper: (1) the photoluminescent CF paper by doping Eu3+ and Tb3+ ions into the crystal lattice of HAPNWs and (2) the superhydrophobic CF paper by coating poly(dimethylsiloxane) on the HAPNW hierarchical structure, which can be applied for self-cleaning and oil/water separation. It is expected that an in situ growth of ultralong HAPNWs will provide an instructive guideline for designing a CF paper with specific functions.

8.
Chemistry ; 27(11): 3786-3792, 2021 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-33200430

RESUMO

Photocatalytic syngas (CO and H2 ) production with CO2 as gas source not only ameliorates greenhouse effect, but also produces valuable chemical feedstocks. However, traditional photocatalytic systems require noble metal or suffers from low yield. Here, we demonstrate that S vacancies ZnIn2 S4 (VS -ZnIn2 S4 ) nanosheets are an ideal photocatalyst to drive CO2 reduction into syngas. It is found that building S vacancies can endow ZnIn2 S4 with stronger photoabsorption, efficient electron-hole separation, and larger CO2 adsorption, finally promoting both hydrogen evolution reaction (HER) and CO2 reduction reaction (CO2 RR). The syngas yield of CO and H2 is therefore significantly increased. In contrast to pristine ZnIn2 S4 , the syngas yield over VS -ZnIn2 S4 can be improved by roughly ≈4.73 times and the CO/H2 ratio is modified from 1:4.18 to 1:1. Total amount of syngas after 12 h photocatalysis is as high as 63.20 mmol g-1 without use of any noble metals, which is even higher than those of traditional noble metal-based catalysts in the reported literatures. This work demonstrates the critical role of S vacancies in mediating catalytic activity and selectivity, and highlights the attractive ability of defective ZnIn2 S4 for light-driven syngas production.

9.
Zhen Ci Yan Jiu ; 45(6): 480-3, 2020 Jun 25.
Artigo em Chinês | MEDLINE | ID: mdl-32643885

RESUMO

OBJECTIVE: To investigate the effect of Baixiao moxibustion at meridian sinew nodal points combined with routine rehabilitation on upper limb motor function in children with spastic hemiplegic cerebral palsy. METHODS: A total of 50 children with spastic hemiplegic cerebral palsy were divided into control group and treatment group using a random number table, with 25 children in each group. The children in the control group were given routine rehabilitation training of the ipsilateral upper and lower limbs, and those in the treatment group were given Baixiao moxibustion at the meridian sinew nodal points of the ipsilateral upper limb in addition to the treatment in the control group, once a day and five times a week. Each course of treatment was 4 consecutive weeks, and both groups were treated for 3 courses. Before treatment and at weeks 4 and 12 of treatment, modified Ashworth score was used to evaluate muscle tension of the ipsilateral upper limb, and 88-item version of the Gross Motor Function Measure (GMFM-88) and Carroll upper extremities functional test (UEFT) were used to assess the motor function of the ipsilateral upper limb. RESULTS: At weeks 4 and 12 of treatment, both groups had a significant reduction in modified Ashworth score (P<0.05) and significant increases in GMFM-88 and UEFT scores (P<0.05). Both groups had significant changes in modified Ashworth score, GMFM-88 score, and UEFT score from week 4 to week 12 of treatment (P<0.05). Compared with the control group at week 12 of treatment, the treatment group had a significant reduction in modified Ashworth score (P<0.05) and significant increases in GMFM-88 and UEFT scores (P<0.05). CONCLUSION: Baixiao moxibustion at meridian sinew nodal points can significantly improve the muscle tension and motor function of the ipsilateral upper limb in children with spastic hemiplegic cerebral palsy, and the improvement becomes more apparent as the treatment lasts longer.


Assuntos
Paralisia Cerebral , Meridianos , Moxibustão , Paralisia Cerebral/terapia , Criança , Hemiplegia , Humanos , Espasticidade Muscular , Extremidade Superior
10.
Org Lett ; 22(9): 3367-3372, 2020 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-32281800

RESUMO

Exploring a collection of naturally occurring imine reductases (IREDs) identified two stereocomplementary IREDs with reducing activity toward sterically hindered 2-aryl-substituted pyrrolines. Using (R)-selective ScIR and (S)-selective SvIR, various chiral 2-aryl-substituted pyrrolidines with excellent enantioselectivity (>99% ee) were stereocomplementarily synthesized in good yield (60-80%), demonstrating the feasibility of IREDs for generating pharmaceutically relevant chiral 2-aryl-substituted pyrrolidine intermediates.


Assuntos
Iminas/metabolismo , Oxirredutases/química , Oxirredutases/metabolismo , Pirrolidinas/síntese química , Iminas/química , Cinética , Preparações Farmacêuticas/síntese química , Pirrolidinas/farmacologia , Estereoisomerismo , Streptomyces/enzimologia
11.
Zhongguo Zhen Jiu ; 40(12): 1304-8, 2020 Dec 12.
Artigo em Chinês | MEDLINE | ID: mdl-33415872

RESUMO

OBJECTIVE: To observe the effect of transcutaneous electrical acupoint stimulation (TEAS) on venous thrombosis and quality of life after lung cancer surgery, basing on the conventional nursing and early functional exercise. METHODS: A total of 120 patients diagnosed as non-small cell lung cancer (NSCLC) and received radical resection of lung cancer surgery for the first time were randomized into a conventional nursing group, a rehabilitation training group and a TEAS group, 40 cases in each group. Conventional nursing was adopted in the conventional nursing group. Conventional nursing combined with early functional exercise were adopted in the rehabilitation training group, the exercise was taken 20 min each time, once in both morning and afternoon for 5 days. On the basis of the treatment in the rehabilitation training group, TEAS was applied at Zusanli (ST 36), Xuehai (SP 10), Sanyinjiao (SP 6), etc. in the TEAS group, with disperse-dense wave in frequency of 30 Hz/100 Hz and tolerable intensity, 30 min each time, once in both morning and afternoon for 5 days. The incidence of venous thrombosis in each group was observed at the 5th day after surgery. Before surgery and at the 5th day after surgery, the Caprini thrombus risk assessment was performed, the Karnofsky performance status (KPS) scale and the functional assessment of cancer therapy-lung (FACT-L) were used to evaluate the quality of life. RESULTS: At the 5th day after surgery, no thrombosis was found in the TEAS group, the incidence of venous thrombosis in the TEAS group was lower than 15.0% (6/40) in the conventional nursing group (P<0.05). At the 5th day after surgery, the Caprini scores were increased in the 3 groups (P<0.01), while that in the TEAS group was lower than the conventional nursing group (P<0.05); the KPS scores were decreased in the 3 groups (P<0.01), while those in the TEAS group and the rehabilitation training group were higher than the conventional nursing group (P<0.01, P<0.05); the total scores and the subitem scores of FACT-L were decreased in the 3 groups (P<0.05), while the total score of FACT-L and the subitem score of lung cancer specificity in the TEAS group were higher than those in the conventional nursing group (P<0.05). CONCLUSION: On the basis of the conventional nursing and early functional exercise, TEAS can reduce the incidence of venous thrombosis, effectively prevent thrombosis and improve quality of life.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Estimulação Elétrica Nervosa Transcutânea , Trombose Venosa , Pontos de Acupuntura , Carcinoma Pulmonar de Células não Pequenas/cirurgia , Humanos , Neoplasias Pulmonares/cirurgia , Qualidade de Vida , Trombose Venosa/etiologia
12.
Ren Fail ; 41(1): 1045-1053, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31809666

RESUMO

A 43-year-old Chinese man with a silicosis history was admitted to our hospital due to bilateral lower extremity edema for 1 year, exacerbating with hematuria for 2 months. He started working as a coal miner 30 years ago, and was diagnosed as silicosis 3 months ago. Lab tests revealed hematuria 3+, proteinuria 3+, and a serum creatinine value 2.47 mg/dl on routine check. He was diagnosed with focal proliferative IgA nephropathy (IgAN) and acute tubulo-interstitial nephritis by renal biopsy. He was treated with corticosteroids and got a remission 4 months later. Immunohistochemical staining showed the deposition of macrophage receptor with collagenous structure (MARCO), nod-like receptor pyrin domain-containing-3 (NLRP3), Caspase-1, apoptosis-associated speck (ASC), interleukin (IL)-1ß, and IL-18 in both glomerular and tubulo-interstitial areas. We proposed that the silicon exposure could be related to his kidney disease in the patient and NLRP3 mediated inflammation might be involved in its pathogenesis which needs further explorations.


Assuntos
Nefropatias/etiologia , Rim/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Silicose/complicações , Adulto , Humanos , Rim/ultraestrutura , Nefropatias/metabolismo , Nefropatias/patologia , Masculino , Silicose/metabolismo
13.
Front Microbiol ; 10: 2559, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31749788

RESUMO

Burkholderia pyrrocinia JK-SH007 is a plant growth-promoting bacteria (PGPB), that can promote the growth of poplar and other trees, and, production of the plant hormone indole-3-acetic acid (IAA) is one of the reasons for this effect. Therefore, the aims of this study were to evaluate the effect of the external environment on the synthesis of IAA by B. pyrrocinia JK-SH007 and to perform a functional analysis of its IAA synthesis pathway. In this study, IAA and its synthetic intermediates indole-3-acetamide (IAM), indole-3-pyruvic acid (IPyA), tryptamine (TAM), and indole-3-acetonitrile (IAN) were detected in B. pyrrocinia JK-SH007 fermentation broth by high-performance liquid chromatography and tandem mass spectrometry (HPLC-MS/MS), and these indolic compounds were also found in the cell-free extraction of B. pyrrocinia JK-SH007, but the genomic analysis of B. pyrrocinia JK-SH007 indicated that IAA biosynthesis was mainly through the IAM and TAM pathways. The effects of L-tryptophan (L-Trp), temperature and pH on the synthesis of IAA were investigated, and the results showed that L-Trp exerted a significant effect on IAA synthesis and that 37°C and pH 7 were the optimal conditions IAA production by B. pyrrocinia JK-SH007. In addition, the protein expression of tryptophan 2-monooxygenase and indoleacetamide hydrolase, which are the key enzymes of the indole acetamide-mediated IAA synthesis pathway, was analyzed, and their activity was verified by substrate feeding experiments. The results revealed the existence of an IAA synthesis pathway mediated by IAM and indicated that this pathway plays a role in B. pyrrocinia JK-SH007. This study lays the foundation for further exploration of the specific pathway and mechanism of IAA synthesis in B. pyrrocinia JK-SH007.

14.
J Org Chem ; 84(22): 14987-14993, 2019 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-31644289

RESUMO

(R)-Amination mediated by (R)-specific ω-transaminases generally requires costly d-alanine in excess to obtain the desired chiral amines in high yield. Herein, a one-pot, trienzymatic cascade comprising an (R)-specific ω-transaminase, an amine dehydrogenase, and a formate dehydrogenase was developed for the economical and eco-friendly synthesis of (R)-chiral amines. Using inexpensive ammonium formate as the sole sacrificial agent, the established cascade system enabled efficient ω-transaminase-mediated (R)-amination of various ketones, with high conversions and excellent ee (>99%); water and CO2 were the only waste products.

15.
Chemistry ; 25(46): 10918-10925, 2019 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-31211454

RESUMO

Security inks based on photoluminescent materials are mostly investigated for security applications, such as information encryption and decryption, anti-counterfeiting, and data storage. Although they are invisible to the naked eye under ambient light, they can be detected under ultraviolet or near-infrared light. Herein, a new kind of secret paper made from network-structured ultralong hydroxyapatite nanowires and cellulose fibers has been developed. White vinegar, a common cooking ingredient, is used as an invisible security ink. Covert information on the secret paper written with white vinegar is totally invisible under natural light, but it can be decrypted and clearly read after exposure to fire; the response time to fire is short (<10 s). The ways of writing on the secret paper are diverse by using various pens loaded with white vinegar.

16.
ACS Nano ; 12(12): 12284-12295, 2018 12 26.
Artigo em Inglês | MEDLINE | ID: mdl-30475582

RESUMO

A variety of biological materials in natural organisms supply a rich source of structural design guidelines and inspirations for the construction of advanced structural materials with excellent mechanical properties. In this work, inspired by the natural nacre and human bone, a kind of flexible macroscopic ribbon fiber made from highly ordered alignment of ultralong hydroxyapatite (HAP) nanowires and sodium polyacrylate (PAAS) with a "brick-and-mortar" layered structure has been developed by a scalable and convenient wet-spinning method. The quasi-long-range orderly liquid crystal of one-dimensional ultralong hydroxyapatite nanowires is employed and spun into the continuous flexible macroscopic ribbon fiber. In this work, highly ordered ultralong HAP nanowires act as the hard "brick" and PAAS acts as the soft "mortar", and the nacre-mimetic layered architecture is obtained. The as-prepared flexible macroscopic HAP/PAAS ribbon fiber exhibits superior mechanical properties, and the maximum tensile strength and Young's modulus are as high as 203.58 ± 45.38 MPa and 24.56 ± 5.35 GPa, respectively. In addition, benefiting from the excellent flexibility and good knittability, the as-prepared macroscopic HAP/PAAS ribbon fiber can be woven into various flexible macroscopic architectures. Additionally, the as-prepared flexible macroscopic HAP/PAAS ribbon fiber can be further functionalized by incorporation of various functional components, such as magnetic and photoluminescent constituents. The as-prepared flexible macroscopic HAP/PAAS ribbon fiber has potential applications in various fields such as smart wearable devices, optical devices, magnetic devices, and biomedical engineering.

17.
Small ; 14(51): e1804321, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30417599

RESUMO

In vivo mineralization is a multistep process involving mineral-protein complexes and various metastable compounds in vertebrates. In this complex process, the minerals produced in the mitochondrial matrix play a critical role in initiating extracellular mineralization. However, the functional mechanisms of the mitochondrial minerals are still a mystery. Herein, an in vitro enzymatic reaction strategy is reported for the generation of biomimic amorphous calcium phosphate (EACP) nanominerals by an alkaline phosphatase (ALP)-catalyzed hydrolysis of adenosine triphosphate (ATP) in a weakly alkalescent aqueous condition (pH 8.0-8.5), which is partially similar to the mitochondrial environment. Significantly, the EACP nanomineral obviously promotes autophagy and osteogenic differentiation of human bone marrow-derived mesenchymal stem cells by activating an AMPK related pathway, and displays a high performance in promoting bone regeneration. These results provide in vitro evidence for the effect of ATP on the formation and stabilization of the mineral in the mineralization process, demonstrating a potential strategy for the preparation of the biomimic mineral for treating bone related diseases.


Assuntos
Biomimética/métodos , Fosfatase Alcalina/metabolismo , Autofagia/fisiologia , Fosfatos de Cálcio/química , Diferenciação Celular/fisiologia , Humanos , Concentração de Íons de Hidrogênio , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Osteogênese/fisiologia
18.
Small ; 14(50): e1803387, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30370652

RESUMO

Efficient utilization of abundant solar energy for clean water generation is considered a sustainable and environment friendly approach to mitigate the global water crisis. For this purpose, this study reports a flexible fire-resistant photothermal paper by combining carbon nanotubes (CNTs) and fire-resistant inorganic paper based on ultralong hydroxyapatite nanowires (HNs) for efficient solar energy-driven water steam generation and water purification. Benefiting from the structural characteristics of the HN/CNT photothermal paper, the black CNT surface layer exhibits a high light absorbability and photothermal conversion capability, the HN-based inorganic paper acts as a thermal insulator with a high temperature stability, low thermal conductivity, and interconnected porous structure. By combining these advantages, high water evaporation efficiencies of 83.2% at 1 kW m-2 and 92.8% at 10 kW m-2 are achieved. In addition, the HN/CNT photothermal paper has a stable water evaporation capability during recycling and long-time usage. The promising potential of the HN/CNT photothermal paper for efficient production of drinkable water from both actual seawater and simulative wastewater samples containing heavy metal ions, dyes, and bacteria is also demonstrated. The highly flexible HN/CNT photothermal paper is promising for application in highly efficient solar energy-driven seawater desalination and wastewater purification.

19.
ACS Nano ; 12(5): 4583-4593, 2018 05 22.
Artigo em Inglês | MEDLINE | ID: mdl-29709183

RESUMO

With the growing popularity of electrical communication equipment, high-performance electromagnetic interference (EMI) shielding materials are widely used to deal with radiation pollution. However, the large thickness and poor mechanical properties of many EMI shielding materials usually limit their applications. In this study, ultrathin and highly flexible Ti3C2T x (d-Ti3C2T x, MXene)/cellulose nanofiber (CNF) composite paper with a nacre-like lamellar structure is fabricated via a vacuum-filtration-induced self-assembly process. By the interaction between one-dimensional (1D) CNFs and two-dimensional (2D) d-Ti3C2T x MXene, the binary strengthening and toughening of the nacre-like d-Ti3C2T x/CNF composite paper has been successfully achieved, leading to high tensile strength (up to 135.4 MPa) and fracture strain (up to 16.7%), as well as excellent folding endurance (up to 14 260 times). Moreover, the d-Ti3C2T x/CNF composite paper exhibits high electrical conductivity (up to 739.4 S m-1) and excellent specific EMI shielding efficiency (up to 2647 dB cm2 g-1) at an ultrathin thickness (minimum thickness 47 µm). The nacre-inspired strategy in this study offers a promising approach for the design and preparation of the strong integrated and flexible MXene/CNF composite paper, which may be applied in various fields such as flexible wearable devices, weapon equipment, and robot joints.

20.
ACS Nano ; 12(4): 3159-3171, 2018 04 24.
Artigo em Inglês | MEDLINE | ID: mdl-29532660

RESUMO

Wallpaper with multiple functions, such as fire resistance and an automatic alarm in fire disasters, will be attractive for the interior decoration of houses. Herein, we report a smart fire alarm wallpaper prepared using fire-resistant inorganic paper based on ultralong hydroxyapatite nanowires (HNs) and graphene oxide (GO) thermosensitive sensors. At room temperature, the GO thermosensitive sensor is in a state of electrical insulation; however, it becomes electrically conductive at high temperatures. In a fire disaster, high temperature will rapidly remove the oxygen-containing groups of GO, leading to the transformation process of GO from an electrically insulated state into an electrically conductive one. In this way, the alarm lamp and alarm buzzer connected with the GO thermosensitive sensor will send out the alerts to people immediately for taking emergency actions. After the surface modification with polydopamine of GO (PGO), the sensitivity and flame retardancy of the GO thermosensitive sensor are further improved, resulting in a low responsive temperature (126.9 °C), fast response (2 s), and sustained working time in the flame (at least 5 min). Compared with combustible commercial wallpaper, the smart fire alarm wallpaper based on HNs and GO (or PGO) is superior owing to excellent nonflammability and high-temperature resistance of HNs, which can protect the GO (or PGO) thermosensitive sensor from the flames. The smart fire alarm wallpaper can be processed into various shapes, dyed with different colors, and printed with the commercial printer and thus has promising applications in high-safety interior decoration of houses.

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