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1.
J Hazard Mater ; 471: 134399, 2024 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-38678713

RESUMO

The metal organic framework (MOFs)-derived porous carbon materials with highly dispersed metal active sites were of the exclusive application foreground in many field, such as catalyst, electrochemistry, adsorption desulfurization and so on. However, the loss issue of metal active sites in MOFs frame was indispensable during the high temperature carbonization because of the lower boiling point of many metals, thus fundamentally affecting the atom-scale uniform distribution merit of MOFs-derived porous carbon materials. This work was to provide a novel strategy to address the loss issue of the active metal volatilization in the fabrication of MOFs-derived porous carbon materials. The ZnO nanosheets were pre-grown on the surface of diatomite by using in-situ microwave-assisted preparation, and thereafter the Zn-containing ZIF-8 particles covered the surface of ZnO nanosheets by virtue of the ZnO-induced growth. The results affirmed that the high content Zn-doped porous carbon materials were achieved and the Zn volatilization in MOFs was restrained on account of the occurrence of ZnO on diatomite (DE) surface during the carbonization. The adsorption desulfurization performance of the ZnO/Zn-embedded porous carbon materials/DE (ZnO/Zn/C@DE) was examined by the sulfur-containing compounds in simulated oil. The adsorption desulfurization performance investigation indicated that the ZnO/Zn/C@DE had the optimum adsorption capacities of 45.3 mg/g for benzothiophene and 37.4 mg/g for thiophene. Nonetheless, the competitive adsorption desulfurization finding of toluene in simulated oil showed that the adsorption capacities of ZnO/Zn/C@DE for TH and BT were dramatically descended, suggesting the presence of S-M interaction, wherein S stood for the S atom in a thiophene molecule and their analogs, and M for Zn atoms in porous carbon materials.

2.
Langmuir ; 40(1): 264-274, 2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38150405

RESUMO

The collaborative lubrication effect based on different lubricating nanostructures could not only overcome the respective drawbacks of different nanostructures as nanoadditives but also comprehensively improve friction performance. For this, we first developed a novel collaborative lubrication nanostructure based on Ag nanowires (NWs) and two-dimensional (2D) Ni-BDC nanosheets (Ag NWs/2D Ni-BDC) by the in situ chemical reduction strategy. The structural characterizations corroborated that Ag NWs with a width of approximately 20-30 nm grew on the surface of 2D Ni-BDC nanosheets, which presented the chemical interface between both. As the nanoadditive applied in oils, the tribological finding confirmed that the Ag NWs/2D Ni-BDC enabled the friction coefficient and wear scar diameter to reduce by 38 and 37% at 0.04 wt % additive content, respectively. The worn surface was characterized by a series of analytical techniques, which basically revealed the friction-reducing and antiwear mechanism based on the layered structure and self-repair effect. Consequently, the nanocomposite structure incorporating the nanowire and 2D nanosheets should be taken into account as a new potential lubricating material.

3.
Langmuir ; 39(41): 14595-14604, 2023 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-37811633

RESUMO

Herein, we successfully constructed a Cu+-doped PVA-derived mesoporous carbon@diatomite (DE) composite by virtue of N2-suffered carbonization and self-reduction at a high temperature. The structure and composition of C/Cu@DE composite adsorbents were determined by a series of characterizations. The results affirmed that Cu+ species are highly scattered in PVA-derived mesoporous carbon, which covered the DE surface. The effect of carbonization temperature on the structure and composition of the C/Cu@DE composite adsorbents were intensively investigated, indicating that the C/Cu@DE composite at an 800 °C carbonization temperature (C/Cu@DE-800 °C) showed the formation of many Cu+ species and preferable hierarchical pore properties. The adsorption experiments of benzothiophene (BT) indicated that C/Cu@DE-800 °C possessed a better adsorption capacity. The adsorption behavior of BT onto C/Cu@DE-800 °C was investigated by a variety of adsorption times, initial concentrations, and recycle times, of which the largest adsorption capacity for BT attained 34.2 mg/g. Furthermore, the adsorption kinetics, intraparticle diffusion, adsorption isotherms, and adsorption thermodynamics of BT onto C/Cu@DE-800 °C was deeply studied, which contributed to the proposed adsorption mechanism.

4.
Pain Ther ; 11(4): 1245-1266, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35969366

RESUMO

BACKGROUND: With increasing life expectancy in China, the associated burden of low back and neck pain (spinal pain) on the healthcare system increases, posing a substantial public health challenge. This study aimed to investigate trends in spinal pain incidence across China from 1990 to 2019 and to predict incidence trends between 2020 and 2030. METHODS: Data were derived from the Global Burden of Disease Study (GBD) 2019. The annual percentage change (APC) and average annual percentage change (AAPC) between 1990 and 2019 were calculated using Joinpoint regression analysis. The effects of age, period, and cohort on spinal pain were estimated by an age-period-cohort model. An autoregressive integrated moving average (ARIMA) model was used to forecast incidence trends from 2020 to 2030. RESULTS: From 1990 to 2019, the age-standardized incidence rate (ASIR) of low back pain (LBP) significantly decreased in both male and female subjects, while the ASIR of neck pain (NP) slightly increased regardless of sex. Joinpoint regression analysis showed that the incidence rates of LBP decreased in all age groups, and incidence rates of NP increased after 45 years old among men and women. The age effects showed that the relative risks (RR) of LBP incidence increased with age, and the group aged 40-49 years had the highest RR for NP incidence, regardless of sex. Period effects showed that the risk of NP continuously increased with increasing time periods, but not in LBP. The cohort effect showed a continuously decreasing trend in later birth cohorts. The prediction results of the ARIMA model show that the ASIR of NP in both male and female subjects in China shows an increasing trend in the next 10 years, and the ASIR of LBP increased in male but decreased in female subjects. CONCLUSION: Spinal pain has remained a major public health burden over the past 30 years in China and will likely increase further with population aging. Therefore, spinal pain should be a priority for future research on prevention and therapy, and is especially critical as the aging population increases in China.

5.
Ann Transl Med ; 9(18): 1421, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34733973

RESUMO

BACKGROUND: Conventional surgical treatment for metacarpal giant cell tumours (GCTs) includes lesion scraping followed by bone grafting or bone cement filling and en bloc resection followed by repair and reconstruction using a vascularised bone flap. However, these methods have inherent shortcomings, including a high postoperative recurrence rate and poor mechanical stability. 3D-printing techniques are increasingly being applied in medicine, and 3D-printed personalised prostheses have achieved good clinical effects in orthopaedic repair and reconstruction. We aimed to investigate the clinical effects of 3D-printed personalised prostheses for bone defect repair and reconstruction following resection of metacarpal GCTs. METHODS: Three patients with metacarpal GCTs were examined in a retrospective cohort study. Through preoperative planning, a 3D-printed personalised prosthesis was designed and created for bone defect repair and reconstruction after tumour resection. Prosthesis fit, limb function, pain on the affected side, and the occurrence of complications were evaluated postoperatively. RESULTS: Postoperative X-ray examination revealed a satisfactory fit of the 3D-printed prosthesis in terms of bone defect size and overall metacarpal shape, as well as good transverse and longitudinal metacarpal arches. The patients also exhibited good function in the affected limb, with good flexion and extension functions in the carpal, metacarpophalangeal, and interphalangeal joints, plus the absence of obvious pain, tumour recurrence, and complications such as pathologic fractures and prosthetic loosening. CONCLUSIONS: When using a 3D-printed personalised prosthesis for bone defect repair and reconstruction following resection of metacarpal GCTs, a good fit with the bone defect can be achieved during prosthetic installation when preoperative planning and design have been adequately performed. Therefore, three-dimensionally printed personalised prostheses can serve as an effective method for the treatment of metacarpal GCTs.

6.
J Orthop Translat ; 29: 163-169, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34277347

RESUMO

BACKGROUND: /Objective: In recent years, prostheses have been widely used for limb reconstruction after pelvic tumour resection. However, prostheses are associated with problems leading to tumour recurrence, poor implant matching, defects after tumour resection, and easy implant looseness or failure. To achieve a precise preoperative design, complete tumour resection, and better anatomical structure matching and prosthesis stability, this study used three-dimensionally (3D)-printed osteotomy guides and personalised prostheses for reconstruction after pelvic tumour resection. This study aimed to explore the early clinical efficacy of 3D printed personalised prostheses for the reconstruction of bone defects after pelvic tumour resection. METHODS: A total of 20 patients (12 males, 8 females) with pelvic tumours surgically treated at our hospital between October 2014 and October 2019 were selected. There were 10 cases each of giant cell bone tumours and osteochondrosarcomas. According to Enneking zoning, there were 11 and 9 cases with tumours located in zones I and II, respectively. All cases were equally divided into conventional and 3D printing groups. For repair and reconstruction, a nail rod system or a steel plate was used in the conventional group while individualised 3D-printed prostheses were used in the 3D printing group. The surgical incision, duration of surgery, intraoperative blood loss, and the negative rate of resection margins in postoperative tumour specimens were examined. The follow-up focused on tumour recurrence, complications, and the Musculoskeletal Tumor Society (MSTS) score. RESULTS: All cases were followed-up for 6-24 months. The average incision length, duration of surgery, amount of intraoperative blood loss, and MSTS score of the 3D printing group were 10.0 ±â€¯3.1 cm, 115.2 ±â€¯25.3 min, 213.2 ±â€¯104.6 mL, 23.8 ±â€¯1.3, respectively, and those of the conventional group were 19.8 ±â€¯8.4 cm, 156.8 ±â€¯61.4 min, 361.4 ±â€¯164.2 mL, and 18.3 ±â€¯1.4, respectively. Histological tumour specimen examination showed nine and three cases with negative resection margins in the 3D printing group and the conventional group, respectively. The abovementioned indicators were significantly different between both groups (P < 0.05). CONCLUSION: Applying 3D printed surgical guides and personalised prostheses for pelvic tumour resection, repair, and reconstruction, as well as preoperative planning and design, enables more accurate tumour resections and better prosthesis-patient matchings, possibly reducing surgical trauma, shortening the duration of surgery, and promoting the functional recovery of patients postoperatively. THE TRANSLATION POTENTIAL OF THIS ARTICLE: Contrary to existing studies on 3D printed personalised prostheses, this study reports the clinical efficacy of the aforementioned technology in treating bone defects in a series of patients who underwent pelvic tumour resection. Moreover, it presents a comprehensive comparison of this technology with conventional procedures, thus strengthening its importance in treatment regimens for reconstructing bone defects.

7.
J Plast Reconstr Aesthet Surg ; 74(9): 2005-2012, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33648867

RESUMO

BACKGROUND: Computed tomography angiography (CTA) has become a widely used imaging modality in vascular surgery. The first web arterial branches of the foot are significant for surgical planning of the donor site for thumb reconstruction. METHODS: We retrospectively analysed 30 thumb reconstructions with free second toe/great toe wrap-around flap transfer, performed between January 2016 and January 2019. The mean patient age was 30 (2-45) years. The causes of hand injury were: 20 machine strangulation injuries, 6 heavy weight smash injuries, and 4 crush injuries. Patients with iodine allergy were excluded preoperatively. We evaluated the effectiveness of CTA in visualizing first web arterial branches and compared it with intraoperative findings. Surgical plan for donor sites was prepared based on the classification of the first web arterial branches. RESULTS: The arterial branches of the patients were classified based on CTA findings as follows: (1) fork type: 24 patients (48 feet, 80%); (2) main trunk type: four patients (8 feet, 13.33%); and (3) side branch type: one patient (2 feet, 3.33%). One case of poor vascular continuity and artifacts in CTA underwent thumb reconstruction with free great toe wrap-around flap transfer. Tissue survival was achieved in all reconstructed thumbs. During the follow-up period (average, 12 months), all reconstructed thumbs exhibited good outcomes. The donor sites on the feet of all patients recovered well. CONCLUSION: CTA allows preoperative assessment of blood supply and planning of donor site. Our results can serve as a reference for surgical planning of the donor site while reducing the occurrence of adverse events.


Assuntos
Artérias/anatomia & histologia , Artérias/diagnóstico por imagem , Angiografia por Tomografia Computadorizada , Pé/irrigação sanguínea , Procedimentos de Cirurgia Plástica/métodos , Retalhos Cirúrgicos/irrigação sanguínea , Polegar/cirurgia , Adolescente , Adulto , Criança , Pré-Escolar , Pé/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Polegar/lesões , Resultado do Tratamento , Adulto Jovem
8.
J Hazard Mater ; 403: 123851, 2021 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-33264927

RESUMO

This report introduced the facile synthesis of the carbon-nanofiber films reinforced by halloysite nanotubes (HNTs) via electrospinning. The HNTs-reinforced N-doped carbon-nanofiber films (PAN/HNTs-CNFs) possessed the higher strength and toughness while keeping the prospective adsorption capability for different sulfur compounds in oil due to the higher N doping content. The PAN/HNTs-CNFs were produced by firstly electrospinning for the HNTs-filled polyacrylonitrile (PAN) nanofiber films, followed by the high-temperature carbonization for the conversion of the polymer films into the carbon-nanofiber films with the N doping. The characterizations testified that the HNTs were capable of fulfilling the uniform and disordered dispersion in the carbon-nanofibers. For overcoming the toughness of the carbon-nanofiber film, the HNTs filling the obviously improved the mechanical performance of the carbon-nanofiber films by the pulling-out and bridging effect. Due to accessing the lipophilic and acid surface, abundant hierarchical pore structure and highly N-doping content, the PAN/HNTs-CNFs exhibited the remarkable adsorption performances for thiophene, benzothiophene, and dibenzothiophene (46.73 mg S/g, 38.4 mg S/g and 35.03 mg S/g for 800 ppm sulfur model oil), especially being suitable to the adsorption of thiophene. Furthermore, the study on the adsorption kinetics, equilibrium isotherms, and thermodynamics of thiophene over the PAN/HNTs-CNFs were conducted to discuss the adsorption mechanism.

9.
Langmuir ; 36(40): 11985-11995, 2020 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-32957786

RESUMO

The usage of direct current (DC) voltage has enormous potential for oil fields due to the effect of wettability alteration. However, the unclear mechanism of the wettability alteration has limited the application of this technology to oil fields. In this study, chemical and physical methods including contact angle tests, Fourier-transform infrared spectroscopy (FTIR) measurements, and atomic force microscope (AFM) experiments were combined to investigate the wettability alteration mechanism for tight sandstones subjected to DC voltage treatment. From the view of a chemical factor, FTIR results show that DC voltage decreases the number of Si-O-Si, C-O-C, C-O, and COOH groups, while it also increases the number of C═O and OH groups. The changes in molecular groups further improve the water-wetting property of tight sandstones. On the other hand, in a physical way, AFM results indicate that DC voltage improves the roughness of the rock surface. At the same time, the wetting state transfers from the Cassie-Baxter to the Wenzel. This increases the contact area of the solid-liquid interface. The augment of roughness and the transfer of the wetting state improve the water-wetting property of tight sandstones. By comparing the influences of both chemical and physical factors on wettability, it is concluded that although roughness indeed affects the wettability, chemical factors play a dominant role in determining the wettability. Achievements in this study can help researchers and engineers better understand the mechanism of wettability alteration and further accelerate the development of tight sandstones with DC voltage-related technology.

10.
ACS Omega ; 5(24): 14212-14220, 2020 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-32596557

RESUMO

Encouragingly, a lot of research studies have demonstrated that two-dimensional (2D) nanosheets applied as an additive in oils show preferable friction-reducing and wear resistance performance. However, the current issue was that an elusive way could be adopted to probe the structure-activity relationship between the structure and tribological properties of bulk layered materials due to the structural evolution during friction testing. In this study, we studied the structure-activity relationship between the structure and tribological properties of bulk layered materials (graphite, h-BN, WS2, and MoS2) by an in situ four-ball friction tester. The morphological and structural changes of the layered materials after in situ four-ball-milling were detected by a series of characterizations. This study revealed the friction-induced nanostructural evolution behaviors of bulk layered materials by a four-ball mode.

11.
Ultrason Sonochem ; 66: 105108, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32247231

RESUMO

In this work, we developed a novel approach for few-layer graphene by employing Li+/Na+ co-intercalated exfoliation assisted by ultrasound method. The experiments were conducted under the ultrasonic power of 300 W and the frequency of 40 kHz without the participation of any organic solvent. The effect of Li+/Na+ proportion on the exfoliation of graphite was intensively investigated. The structure and morphology of the as-exfoliated graphene nanosheets (UGN) was determined by a series of characterizations. The results showed that the thicknesses of the as-exfoliated graphene nanosheets were about 2.38-2.56 nm (about 7-8 layers) at the optimal Li+/Na+ ratio. The potential application of the as-exfoliated graphene nanosheets as additive in grease was evaluated by four-ball friction tester. The results demonstrated that the antifriction and antiwear performances of the grease with 0.06 wt% graphene were significantly improved by 21.35% and 30.32% relative to pure grease, respectively. The friction mechanism was proposed by detecting the worn surfaces.

12.
Ecotoxicol Environ Saf ; 196: 110555, 2020 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-32247961

RESUMO

A strategy for clean fuel by selective adsorption processing was deemed to be convenient and environmental-friendly in past decades. However, the development of adsorption desulfurization was tremendously subject to the fabrication of high-performance adsorbents with large capacity and high stability. Herein, we designed a novel route to fabricate the cloth-like carbon nanofiber film with a hierarchical porous structure by electrospinning. The structure and properties of the cloth-like carbon nanofiber films were determined by a series of characterizations. Subsequently, the desulfurization performance of the cloth-like carbon nanofiber films was examined by the simulated thiophene (TH) oil. Furthermore, the effect of adsorption conditions on the adsorption capacity was intensively investigated, such as carbonization temperature, initial concentration and desulfurization temperature. The results found that at optimal calcination temperature of 700 °C, the cloth-like carbon nanofiber films possessed the highest micropore volume (Vmic = 0.185 m3/g) and adsorption capacity (qe = 96.6 mg/g) at 800 mg/L initial concentration under the adsorption temperature of 25 °C. The results corroborated that the physical properties of the cloth-like carbon nanofiber films with the surface area of 417.8 m2/g, the total pore volume of 0.187 cm3/g and average pore diameter of 1.36 nm had an important influence on the high adsorption capacity. On this basis, the adsorption experimental data were best fitted to pseudo-second-order kinetic and Langmuir isotherm models. Furthermore, the other highlight of the cloth-like carbon nanofiber films was convenient for the separation from oil, thus achieving the desirable reused performance.


Assuntos
Carbono/química , Óleos Combustíveis/análise , Nanofibras/química , Compostos de Enxofre/isolamento & purificação , Adsorção , Cinética , Porosidade , Propriedades de Superfície , Temperatura , Têxteis
13.
J Hazard Mater ; 389: 121879, 2020 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-31859165

RESUMO

The novel nitrogen-doped porous carbon nanofibers film (PAN-CNFs) had been successfully prepared by electrospinning with polyacrylonitrile as carbon precursor after calcination under N2 atmosphere. The structure and physical properties of PAN-CNFs were determined by a series of characterizations. The results showed that the PAN-CNFs-800 have the higher N content (10.02 wt.%), larger surface area (354.327 m2/g) and optional Vmic/VTotal (28.14 %). The adsorption desulphurization was examined by thiophene (TH) simulated oil. The experimental results demonstrated that the PAN-CNFs were the desirable adsorption materials as alternative candidate in present adsorption technique. Furthermore, the pseudo order kinetics and adsorption isotherm of the PAN-CNFs-800 was intensive studied, which exhibited good adsorptive capacity for thiophene (TH) reached 113.33 mg/L according to the Langmuir isotherm model and maintained promising recycling reusing performance. The adsorption mechanism was proposed by these models, which should be attributed to the cooperating effect of the proper pore structure and the π-π complexation interactions.

14.
ACS Omega ; 4(6): 9823-9827, 2019 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-31460072

RESUMO

A facile approach was developed to produce MoS2 nanosheets by ultrasound-assisted reflux exfoliation, which was highly efficient for large-scale production and sustainable for environment. The interlayer force of bulk MoS2 was first exhausted in employing LiOH/NaOH solution by reflux and thereafter quickly exfoliated by ultrasound. The lateral size of the as-prepared MoS2 nanosheets with about 2-9 layers became smaller. Definitely, the average friction coefficient and wear scar diameter of 0.08 wt % MoS2-based oil decreased by about 21.87 and 38.09% relative to the base oil, which displayed better antifriction and antiwear performances.

15.
RSC Adv ; 9(30): 17016-17024, 2019 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-35519880

RESUMO

The exfoliation of bulk MoS2 into few layers has attracted considerable attention as 2D nanomaterials in the past decade. We developed a facile approach for producing MoS2 nanosheets by hydrothermal-assisted shearing exfoliation based on organic-free strategy. This original exfoliation was highly efficient for large-scale production and sustainable for the environment. The thickness of the as-exfoliated MoS2 nanosheets was about 4-6 layers, and the lateral size became smaller from hydrothermal processing to shearing. The hydrothermal processing with the participation of ammonium carbonate played an important role in hydrothermal-assisted shearing exfoliation. As a prospective application, the antifriction performance of the as-exfoliated MoS2 nanosheets in oil was evaluated using a ball-on-ball mode. Evidently, the average friction coefficient and wear scar diameter of 0.08 wt% MoS2-based oil dropped to about 20.66% and 47.27% relative to those of the base oil, which exhibited an excellent antifriction and antiwear ability.

16.
ACS Omega ; 3(11): 15002-15008, 2018 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-31458166

RESUMO

One-dimensional MoS2 nanotubes with the specific surface area of 89.34 m2/g and the average pore size of 2.52 nm were successfully synthesized by the thermolytical approach assisted by halloysite nanotubes. The tribological properties of MoS2 nanotubes with good dispersion in oil were tested with a four-ball wear tester. The tribological testing results indicated that the average friction coefficient and the average wear scar diameter of the 0.08 wt % MoS2-based oil at 25 °C decreased about 39.2 and 35.0%, respectively, compared to those of the 150 SN base oil, indicating that the as-prepared MoS2 nanotubes as a lubricating additive can enhance the tribological performances. Finally, the lubrication mechanism of MoS2 nanotubes was put forward.

17.
Ecotoxicol Environ Saf ; 148: 585-592, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29127821

RESUMO

The exploration of the relationship between zeolite composition and adsorption performance favored to facilitate its better application in removal of the hazardous substances from water. The adsorption capacity of rhodamine B (RB) onto Beta zeolite from aqueous solution was reported. The relationship between SiO2/Al2O3 ratio and adsorption capacity of Beta zeolite for RB was explored. The structure and physical properties of Beta zeolites with various SiO2/Al2O3 ratios were determined by XRD, FTIR, TEM, BET, UV-vis and so on characterizations. The adsorption behavior of rhodamine B onto Beta zeolite matched to Langmuir adsorption isotherm and more suitable description for the adsorption kinetics was a pseudo-second-order reaction model. The maximum adsorption capacity of the as-prepared Beta zeolite with SiO2/Al2O3 = 18.4 was up to 27.97mg/g.


Assuntos
Rodaminas/análise , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Zeolitas/química , Adsorção , Óxido de Alumínio/química , Cinética , Modelos Teóricos , Dióxido de Silício/química , Soluções , Propriedades de Superfície
18.
Mater Sci Eng C Mater Biol Appl ; 78: 362-369, 2017 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-28575996

RESUMO

Mechanical properties and anti-infection are two of the most concerned issues for artificial bone grafting materials. Bone regeneration porous scaffolds with sustained drug release were developed by freeze-drying the mixture of nanosized drug-loaded halloysite nanotubes (HNTs) and gelatin. The scaffolds showed porous structure and excellent biocompatibility. The mechanical properties of the obtained composite scaffolds were enhanced significantly by HNTs to >300%, comparing to those of gelatin scaffold, and match to those of natural cancellous bones. The ibuprofen-loaded HNTs incorporated in the scaffolds allowed extended drug release over 100h, comparing to 8h when directly mixed the drug into the gelatin scaffold. The biological properties of the composite scaffolds were investigated by culturing MG63 cells on them. The HNTs/gelatin scaffolds with excellent mechanical properties and sustained drug release could be a promising artificial bone grating material.


Assuntos
Nanotubos , Silicatos de Alumínio , Argila , Gelatina , Porosidade , Alicerces Teciduais
19.
J Nanosci Nanotechnol ; 16(1): 1155-9, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27398579

RESUMO

SiO2-modified substrate supported compact ZSM-5 membranes with high permeance were prepared using the secondary nucleation method. The synthesis mixture had a molar composition of 10Na2O:84SiO2: 100NaCI:5TPABr:3500H2O. In order to obtain high permeance, a SiO2 meso- porous top layer was added to the macroporous substrate in this study. The SEM images of the seed layer indicate that about 400-500 nm round shaped seeds consisting of 60 nm zeolites fully covered the modifying substrate. The XRD patterns of the zeolite membranes show the purity of the ZSM-5 crystal phase, and reveal the formation of a random orientation on the SiO2-modified substrate. The SEM images of the zeolite membranes indicate that the membranes consist of highly intergrown crystals, with a maximum thickness of about 30 µm. The results of gas permeability studies indicate that the SiO2-modified substrate supported ZSM-5 membranes show good permeance, with the maximum H2permeance achieved being 12.5 x 10⁻7 mol s⁻¹ m⁻² Pa⁻¹. The maximum H2/N2 and H2/CO permselectivities were 4.01 and 4.37 respectively, which are higher than those of the corresponding Knudsen diffusion. The method used resulted in high permeance, while keeping the sustainable permselectivity, and is therefore desirable for practical applications.

20.
Water Sci Technol ; 73(3): 486-92, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26877029

RESUMO

A novel composite electrode material based on a N-doped TiO2-loaded NaY zeolite membrane (N-doped TiO2/NaY zeolite membrane) for photoelectrocatalysis was presented. X-ray diffraction (XRD), scanning electron microscopy (SEM), UV-visible (UV-vis) and X-ray photoelectron spectroscopy (XPS) characterization techniques were used to analyze the structure of the N-doped TiO2/NaY zeolite membrane. The XRD and SEM results verified that the N-doped TiO2 nanoparticles with the size of ca. 20 nm have been successfully loaded on the porous stainless steel-supported NaY zeolite membrane. The UV-vis result showed that the N-doped TiO2/NaY zeolite membrane exhibited a more obvious red-shift than that of N-TiO2 nanoparticles. The XPS characterization revealed that the doping of N element into TiO2 was successfully achieved. The photoelectrocatalysis performance of the N-doped TiO2/NaY zeolite membrane composite electrode material was evaluated by phenol removal and also the effects of reaction conditions on the catalytic performance were investigated. Owing to exhibiting an excellent catalytic activity and good recycling stability, the N-doped TiO2/NaY zeolite membrane composite electrode material was of promising application for photoelectrocatalysis in wastewater treatment.


Assuntos
Fenóis/química , Fotólise , Titânio/química , Poluentes Químicos da Água/química , Zeolitas/química , Eletrodos , Nitrogênio/química , Sódio/química , Ítrio/química
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