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1.
Artigo em Inglês | MEDLINE | ID: mdl-37484699

RESUMO

Objective: To describe the sonographic features of pure mucinous carcinoma with micropapillary pattern (MUMPC) and compare with different pathological type of mucinous breast carcinoma. Methods: Subjects were retrospectively reviewed at Suzhou Municipal Hospital from January 2015 to June 2019. Sonographic features of 49 cases (9 MUMPC, 19cPMBC, and 21 MMBC) pathologically confirmed MBC were recorded according to the Breast Imaging Reporting and Data System (BI-RADS) lexicon. The differences in sonographic features among different type of mucinous breast carcinoma were discussed, including clinical features and sonographic features, shape, lesion boundary, peripheral hyperechoic ring, echo pattern, posterior acoustic feature, thickness peripheral hyperechoic area, and blood flow. Results: All MUMPC had no lymph node metastasis (88.9%, 8/9), and most of the MUMPC showed no thickness peripheral hyperechoic area (88.9%, 8/9) and blood flow (55.6%, 5/9) within the tumor. Furthermore, MUMPC had mixed cystic and solid components (33.3%, 3/9) and solid echoic (66.7%, 6/9) structures, with regular shape (66.7%, 6/9) and peripheral hyperechoic ring (66.7%, 6/9). Seven cases of the MUMPC showed circumscribed margin (77.8%, 7/9), and there was significant difference among the three groups (p < 0.05). In addition, there were 7 cases (77.8%, 7/9) of MUMPC tumor ≤2cm, which was significantly different from cPMBC (26.3%, 5/19) and MMBC (28.6%, 6/21) (p < 0.05). There was no significant difference in ultrasonographic features of MBC with different sizes when stratified by tumor size (p > 0.05). Conclusion: Most of the MUMPC showed a circumscribed margin, peripheral hyperechoic ring, and without lymph node metastasis and thickness peripheral hyperechoic area. However, it is challenging to distinguish MUMPC from PMBC and MMBC on ultrasound. Future research should focus on developing novel analysis methods for ultrasound imaging, conducting studies with larger sample sizes and diverse population groups.

2.
Environ Res ; 236(Pt 1): 116736, 2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37495064

RESUMO

Nanocellulose aerogel has the advantages of porosity, low density and high specific surface area, which can effectively realize the adsorption and treatment of wastewater waste gas. The methods of preparing nanocellulose mainly include mechanical, chemical and biological methods. Nanocellulose is formed into nanocellulose aerogel after gelation, solvent replacement and drying processes. Based on the advantages of easy modification of nanocellulose aerogels, nanocellulose aerogels can be functionalized with conductive fillers, reinforcing fillers and other materials to give nanocellulose aerogels in electrical, mechanical and other properties. Through functionalization, the properties of nanocellulose composite aerogel such as hydrophobicity and adsorption are improved, and the aerogel is endowed with the ability of electrical conductivity and electromagnetic shielding. Through functionalization, the applicability and general applicability of nanocellulose composite aerogel in the field of environmental protection are improved. In this paper, the preparation and functional modification methods of nanocellulose aerogels are reviewed, and the application prospects of nanocellulose composite aerogels in common environmental protection fields such as dye adsorption, heavy metal ion adsorption, gas adsorption, electromagnetic shielding, and oil-water separation are specifically reviewed, and new solutions are proposed.


Assuntos
Celulose , Conservação dos Recursos Naturais , Celulose/química , Metais , Porosidade , Solventes
3.
Molecules ; 28(8)2023 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-37110726

RESUMO

The performance of a Ce(III)-4,4',4″-((1,3,5-triazine-2,4,6-triyl) tris (azanediyl)) tribenzoic acid-organic framework (Ce-H3TATAB-MOFs) for capturing excess fluoride in aqueous solutions and its subsequent defluoridation was investigated in depth. The optimal sorption capacity was obtained with a metal/organic ligand molar ratio of 1:1. The morphological characteristics, crystalline shape, functional groups, and pore structure of the material were analyzed via SEM, XRD, FTIR, XPS, and N2 adsorption-desorption experiments, and the thermodynamics, kinetics, and adsorption mechanism were elucidated. The influence of pH and co-existing ions for defluoridation performance were also sought. The results show that Ce-H3TATAB-MOFs is a mesoporous material with good crystallinity, and that quasi-second kinetic and Langmuir models can describe the sorption kinetics and thermodynamics well, demonstrating that the entire sorption process is a monolayer-governed chemisorption. The Langmuir maximum sorption capacity was 129.7 mg g-1 at 318 K (pH = 4). The adsorption mechanism involves ligand exchange, electrostatic interaction, and surface complexation. The best removal effect was reached at pH 4, and a removal effectiveness of 76.57% was obtained under strongly alkaline conditions (pH 10), indicating that the adsorbent has a wide range of applications. Ionic interference experiments showed that the presence of PO43- and H2PO4- in water have an inhibitory effect on defluoridation, whereas SO42-, Cl-, CO32-, and NO3- are conducive to the adsorption of fluoride due to the ionic effect.

4.
Molecules ; 28(6)2023 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-36985453

RESUMO

With the increasing pollution of electromagnetic (EM) radiation, it is necessary to develop low-cost, renewable electromagnetic interference (EMI) shielding materials. Herein, wood-derived carbon (WC) materials for EMI shielding are prepared by one-step carbonization of renewable wood. With the increase in carbonization temperature, the conductivity and EMI performance of WC increase gradually. At the same carbonization temperature, the denser WC has better conductivity and higher EMI performance. In addition, due to the layered superimposed conductive channel structure, the WC in the vertical-section shows better EMI shielding performance than that in the cross-section. After excluding the influence of thickness and density, the specific EMI shielding effectiveness (SSE/t) value can be calculated to further optimize tree species. We further discuss the mechanism of the influence of the microstructure of WC on its EMI shielding properties. In addition, the lightweight WC EMI material also has good hydrophobicity and heat insulation properties, as well as good mechanical properties.

5.
Molecules ; 28(4)2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36838820

RESUMO

Self-supporting electrode materials with the advantages of a simple operation process and the avoidance of the use any binders are promising candidates for supercapacitors. In this work, carbon-based self-supporting electrode materials with nanosheets grown on Al foil were prepared by combining hydrothermal reaction and the one-step chemical vapor deposition method. The effect of the concentration of the reaction solution on the structures as well as the electrochemical performance of the prepared samples were studied. With the increase in concentration, the nanosheets of the samples became dense and compact. The CNS-120 obtained from a 120 mmol zinc nitrate aqueous solution exhibited excellent electrochemical performance. The CNS-120 displayed the highest areal capacitance of 6.82 mF cm-2 at the current density of 0.01 mA cm-2. Moreover, the CNS-120 exhibited outstanding rate performance with an areal capacitance of 3.07 mF cm-2 at 2 mA cm-2 and good cyclic stability with a capacitance retention of 96.35% after 5000 cycles. Besides, the CNS-120 possessed an energy density of 5.9 µWh cm-2 at a power density of 25 µW cm-2 and still achieved 0.3 µWh cm-2 at 4204 µW cm-2. This work provides simple methods to prepared carbon-based self-supporting materials with low-cost Al foil and demonstrates their potential for realistic application of supercapacitors.


Assuntos
Araceae , Carbono , Capacitância Elétrica , Eletrodos , Gases
6.
Int J Biol Macromol ; 231: 123343, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36682656

RESUMO

Wooden building materials have advantages in terms of biodegradability, non-toxicity, pollution-free and recycling. Currently, applications of natural wood are extremely limited because of low density, low strength and toughness. Therefore, we reported an effective modification strategy with nano-scale cellulose nanofibrils design to prepare a synergistically enhanced cellulosic material. Via three steps: i) the secondary alcohol hydroxyl groups in C2, C3 position were cut; ii) oxidize the hydroxyl group at C2, C3 position to achieve dialdehyde cellulose; and iii) oxidized again to obtain dicarboxylic cellulose. Subsequently, thanks to the regulation of the average moisture content, the moisture content in the wood surface and subsurface increased in a short time. The wood softening layer contributes to the hotpressing treatment of the wood. The mechanical properties and dimensionality have been greatly improved. The obtained delignified oxidated hot-pressed wood with 0.55 mmol/g carboxyl group content demonstrates excellent strength of 328.8 ± 7.43 MPa and Young's modulus of 8.1 ± 0.14 GPa, which is twice than that of natural wood. Delignified oxidated hot-pressed wood also shows exceptional toughness of 8.3 ± 0.28 MJ/m3. Other than that, the shore hardness indicates 0.55 mmol/g carboxylic group, which could increase the hardness at the wood surface hardness to 72.5 ± 4.29°.


Assuntos
Celulose , Madeira , Dureza
7.
Polymers (Basel) ; 14(24)2022 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-36559784

RESUMO

The occurrence of fluoride contamination in drinking water has gained substantial concern owing to its serious threat to human health. Traditional adsorbents have shortcomings such as low adsorption capacity and poor selectivity, so it is urgent to develop new adsorbents with high adsorption capacity, renewable and no secondary pollution. In this work, magnetic electrospun La-Mn-Fe tri-metal oxide nanofibers (LMF NFs) for fluoride recovery were developed via electrospinning and heat treatment, and its defluoridation property was evaluated in batch trials. Modern analytical tools (SEM, BET, XRD, FTIR) were adopted to characterize the properties of the optimized adsorbent, i.e., LMF11 NFs with a La:Mn molar ratio of 1:1. The surface area calculated via BET method and pHpzc assessed using pH drift method of LMF11 NFs were 55.81 m2 g-1 and 6.47, respectively. The results indicated that the adsorption amount was highly dependent on the pH of the solution, and reached the highest value at pH = 3. The kinetic behavior of defluoridation on LMF11 NFs was dominated by the PSO model with the highest fitted determination coefficients of 0.9999. Compared with the other three isotherm models, the Langmuir model described defluoridation characteristics well with larger correlation coefficients of 0.9997, 0.9990, 0.9987 and 0.9976 at 15 °C, 25 °C, 35 °C and 45 °C, respectively. The optimized LMF11 NFs exhibited superior monolayer defluoridation capacities for 173.30-199.60 mg F-/g at pH 3 at 15-45 °C according to the Langmuir isotherm model. A thermodynamic study proved that the defluoridation by LMF11 NFs is a spontaneous, endothermic along with entropy increase process. In addition, the LMF11 NFs still showed high defluoridation performance after three reused cycles. These findings unveil that the synthesized LMF11 NFs adsorbent is a good adsorbent for fluoride remediation from wastewater owing to its low cost, high defluoridation performance and easy operation.

8.
RSC Adv ; 12(47): 30522-30528, 2022 Oct 24.
Artigo em Inglês | MEDLINE | ID: mdl-36337969

RESUMO

A La-based adsorbent was prepared with La(NO3)3·6H2O, 2-methylimidazole and DMF via amide-hydrolysis and used for fluoride decontamination from aqueous water. The obtained adsorbent was lanthanum methanoate (La(COOH)3). The effects of pH value, initial F- concentration and interfering ions on defluoridation properties of as-prepared La(COOH)3 were assessed through batch adsorption tests. The adsorption kinetics, isotherm models and thermodynamics were employed to verify the order, nature and feasibility of La(COOH)3 towards fluoride removal. The results imply that La(COOH)3 is preferable for defluoridation over a wide pH range of 2 to 9 without interference. Simultaneously, the defluoridation process of La(HCOO)3 accords to the pseudo-second order model and Langmuir isotherm, revealing chemical adsorption is the main control step. The maximum fluoride capture capacities of La(COOH)3 at 30, 40 and 50 °C are 245.02, 260.40 and 268.99 mg g-1, respectively. The mechanism for defluoridation by La(COOH)3 was revealed by PXRD and XPS. To summarize, the as-synthesized La based adsorbent could serve as a promising adsorbent for defluoridation from complex fluoride-rich water.

9.
J Org Chem ; 82(10): 5204-5211, 2017 05 19.
Artigo em Inglês | MEDLINE | ID: mdl-28459566

RESUMO

The first heterogeneous gold(I)-catalyzed [2 + 2 + 1] annulation of terminal alkynes, nitriles, and oxygen atoms has been achieved by using an MCM-41-immobilized phosphine-gold(I) complex as catalyst and 8-methylquinoline N-oxide as oxidant under mild conditions, yielding a variety of 2,5-disubstituted oxazoles in good to excellent yields with broad substrate scope. The new heterogeneous gold(I) catalyst can easily be recovered by simple filtration of the reaction solution and recycled for at least eight times without significant loss of activity.

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