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1.
Heliyon ; 10(9): e29645, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38699018

RESUMO

Porous-activated carbons (ACs) derived from Moroccan pine cones (PC) were synthesised by a two step-chemical activation/carbonisation method using phosphoric acid (PC-H) and zinc chloride (PC-Z) as activating agents and used for the adsorption of bisphenol A (BPA) from water. Several techniques (TGA/DTA, FT-IR, XRD, SEM and BET) were used to determine the surface area and pore characterisation and variations during the preparation of the adsorbents. The modification significantly increased the surface area of both ACs, resulting in values of 1369.03 m2 g-1 and 1018.86 m2 g-1 for PC-H and PC-Z, respectively. Subsequent adsorption tests were carried out, varying parameters including adsorbent dosage, pH, initial BPA concentration, and contact time. Therefore, the highest adsorption capacity was observed when the BPA molecules were in their neutral form. High pH values were found to be unfavourable for the removal of bisphenol A from water. The results showed that BPA adsorption kinetics and isotherms followed pseudo-second-order and Langmuir models. Thermodynamic studies indicated that the adsorption was spontaneous and endothermic. Besides, the regeneration of spent adsorbents demonstrated their reusability. The adsorption mechanisms can be attributed to physical adsorption, hydrogen bonds, electrostatic forces, hydrophobic interactions, and π-π intermolecular forces.

2.
Heliyon ; 9(1): e12975, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36711297

RESUMO

There have been many investigations to improve both the physical and mechanical properties of oil well cement using a wide range of materials. Most of these additives are expensive and practically ineffective. In this article, a comprehensive evaluation was conducted for using Austrian pinecones powder (APCP) as an inexpensive supplementary cementing material (SCM) for well cement. Firstly, Portland cement class G was characterized based on X-Ray Fluorescence (XRF), X-Ray Diffraction (XRD). In this paper, the properties of the cement systems include rheological parameters, density, slurry stability (free water test, and sedimentation test), water absorption, porosity, permeability, the volume of fluid loss, pH value, thermogravimetric analysis, and the mechanical characteristics (in terms of compressive strength, tensile strength, flexural strength, and shear strength bond) were investigated in details. The cement sample containing the APCP was also examined using scanning electron microscopy (SEM). According to the experimental results, adding APCP led to increasing in rheological parameters. Also, led to decreasing in fluid loss, free water, sedimentation effect, and density which positively affects the preservation of the original properties of cement slurry. The results also showed a decrease in the permeability of cement samples and an increase in the porosity and the ability to absorb water. The addition of APCP did not significantly affect the pH values. The addition of APCP also deteriorated the mechanical properties of the cement samples. The addition of the APCP has contributed to an increase in total weight loss at high temperatures. So, the APCP can be considered as a new filler for well cement due to its ability to fill the pores in the cement matrix and at the same time improve some properties of the well cement such as density, free water, sedimentation, and fluid loss.

3.
Front Plant Sci ; 13: 1042332, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36438091

RESUMO

Pine cones are important forest products, and the picking process is complex. Aiming at the multi-objective and dispersed characteristics of pine cones in the forest, a machine vision detection model (EBE-YOLOV4) is designed to solve the problems of many parameters and poor computing ability of the general YOLOv4, so as to realize rapid and accurate recognition of pine cones in the forest. Taking YOLOv4 as the basic framework, this method can realize a lightweight and accurate recognition model for pine cones in forest through optimized design of the backbone and the neck networks. EfficientNet-b0 (E) is chosen as the backbone network for feature extraction to reduce parameters and improve the running speed of the model. Channel transformation BiFPN structure (B), which improves the detection rate and ensures the detection accuracy of the model, is introduced to the neck network for feature fusion. The neck network also adds a lightweight channel attention ECA-Net (E) to solve the problem of accuracy decline caused by lightweight improvement. Meanwhile, the H-Swish activation function is used to optimize the model performance to further improve the model accuracy at a small computational cost. 768 images of pine cones in forest were used as experimental data, and 1536 images were obtained after data expansion, which were divided into training set and test set at the ratio of 8:2. The CPU used in the experiment was Inter Core i9-10885@2.40Ghz, and the GPU was NVIDIA Quadro RTX 5000. The performance of YOLOv4 lightweight design was observed based on the indicators of precision (P), recall (R) and detection frames per second (FPS). The results showed that the measurement accuracy (P) of the EBE-YOLOv4 was 96.25%, the recall rate (F) was 82.72% and the detection speed (FPS) was 64.09F/S. Compared with the original YOLOv4, the precision of detection had no significant change, but the speed increased by 70%, which demonstrated the effectiveness of YOLOv4 lightweight design.

4.
J Food Biochem ; 46(7): e14135, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35301731

RESUMO

Pinus koraiensis needles (PKN) and cones (PKC) have been shown to protect against inflammation and pathogenic bacteria. We investigated the efficacies and action mechanisms of topical applications of 1,3-butylene glycol (BG) extracts and oral administration of their water extracts on atopic dermatitis (AD) symptoms. After exposing HaCaT cells and Nc/Nga mice dorsal skins to 2,4-dinitrochlorobenzene (DNCB) to induce atopic dermatitis models, they were topically applied BG (AD-control), 30% PKNX, or 30% PKCX to the skin lesions and fed water extracts (0.5%) in high-fat diets for 5 weeks. Normal-control mice had no DNCB exposure. Serum immunoglobulin E (IgE), IL-4, and TNF-α levels and gene expressions of TNF-α, IL-4, IL-6, and IFN-γ in the dorsal skin and HaCaT cells were measured. The AD-control mice elevated TNF-α and IL-6 mRNA levels in HaCaT cells. Both extracts attenuated clinical AD symptoms in AD-induced Nc/Nga mice: PKNX improved hemorrhage, erythema, and lichenification of dorsal skin better than PKCX while both similarly alleviated erythema, edema, excoriation, and itching behavior. PKCX reduced IgE contents and increased filaggrin mRNA expression better than PKNX, but PKNX reduced lipid peroxides and mRNA levels of TNF-α and IL-4 in the dorsal skin. In the histological analysis of the dorsal skin, the administration of both extracts significantly decreased mast cell numbers, immune cell infiltration, gaps between the epidermis and dermis, and abnormal cell and nucleus shapes. In conclusion, both PKCX and PKNX treatment alleviated the DNCB-induced clinical symptoms of AD by alleviating immune-related symptoms and inflammation in partially different pathways. Therefore, PKNX and PKCX may be effective for AD therapy. PRACTICAL APPLICATIONS: Atopic dermatitis (AD) is related to an overly activated immune response, and it has steadily increased last 3 decades. However, no optimal sustainable treatments are available. Pinus koraiensis needles and cones extracts have been used for anti-inflammatory and antimicrobial treatment. The present study demonstrated that their intake and topical administration onto the AD lesion alleviated clinical AD symptoms associated with reduced proinflammatory cytokines, mast cell numbers, and immune cell infiltrates to maintain dermal structure with maintaining filaggrin expression in AD-induced HaCaT cells and Nc/Nga mice. These results suggested that Pinus koraiensis needles and cones extracts can be developed and applied as beneficial alternative therapies for AD.


Assuntos
Dermatite Atópica , Pinus , Animais , Dermatite Atópica/induzido quimicamente , Dermatite Atópica/tratamento farmacológico , Dinitroclorobenzeno/efeitos adversos , Células HaCaT , Humanos , Imunoglobulina E/efeitos adversos , Inflamação , Interleucina-4 , Interleucina-6 , Camundongos , RNA Mensageiro , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo , Água
5.
Environ Sci Pollut Res Int ; 27(12): 13915-13929, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32036521

RESUMO

Activated carbons (ACs) from Pinus canariensis cones were developed by KOH chemical activation. The effect of the impregnation KOH/carbonized cones ratio (IR = 1, 2, or 3) and temperature (873, 973, 1073 K) on main chemical, textural, and morphological characteristics of the resulting ACs was systematically examined. CO2 adsorption capacity from gaseous streams was evaluated by gravimetric adsorption tests, and the analysis of breakthrough curves was determined in a packed-bed column at 303 K and atmospheric pressure. Comparison of CO2 adsorption capacities of the ACs at 273 K and 303 K at equilibrium showed that those samples developed at 973 K with IR = 3 (BET surface area ~ 1900 m2 g-1) attained the highest values (6.4 mmol g-1 and 1.9 mmol g-1, respectively), even though the ACs obtained at 1073 K with the same IR exhibited the largest surface area (2200 m2 g-1). Thermodynamic parameters evaluated from CO2 adsorption isotherms determined in the range 273-333 K for the former sample pointed to a physisorption, spontaneous, and exothermic process; isosteric heat of adsorption was also estimated for the range of surface coverage of the equilibrium isotherms. The kinetics of CO2 adsorption onto all the ACs was successfully described by the linear driving force model. The breakthrough curves were properly represented by the Thomas' model, the longest breakthrough time and highest adsorption capacity being also attained for the bed packed with the ACs developed at 973 K with IR = 3. Higher CO2 adsorption capacities of the ACs were directly related to the presence of narrow micropores (< 0.9 nm) induced by the stronger activation conditions. However, an excessively severe combination of the IR and activation temperature exerted a negative influence on CO2 adsorption onto the ACs, likely due to micropores widening.


Assuntos
Carvão Vegetal , Pinus , Adsorção , Dióxido de Carbono , Cinética
6.
Molecules ; 23(6)2018 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-29890658

RESUMO

A novel chitosan microsphere for encapsulating pine cone polyphenols (PP) from P. koraiensis was successfully prepared using an emulsion crosslinking technique. The characteristics of pine polyphenol-loaded microspheres (PPM) were determined using scanning electron microscopy (SEM) and a laser particle size detector. It was found that PPMs were spherical in shape with uniform particle size distribution patterns. The drug content and encapsulation rate of the microspheres were 7.47% and 73.6%, respectively, at a Ch/GA mass ratio of 0.7. The animal experiments showed that PPM had a stronger radiation protective effect than PP. PPM significantly increased the immune organ indices, the quantity of marrow DNA, the superoxide dismutase (SOD) activity, the splenocyte proliferation index, and the phagocytosis activity of monocytes. PPM also decreased the numbers of micronuclei in bone marrow cells and malondialdehyde (MDA) levels in plasma in mice exposed to 60Co γ-irradiation. In addition, gender differences in biological responses to exposure to radiation were observed.


Assuntos
Quitosana/química , Radioisótopos de Cobalto/efeitos adversos , Microesferas , Pinus/química , Polifenóis/farmacologia , Lesões por Radiação/prevenção & controle , Protetores contra Radiação/farmacologia , Animais , Peso Corporal/efeitos dos fármacos , Medula Óssea/efeitos dos fármacos , Dano ao DNA , Feminino , Masculino , Malondialdeído/metabolismo , Camundongos Endogâmicos ICR , Microscopia Eletrônica de Varredura , Fagocitose/efeitos dos fármacos , Polifenóis/administração & dosagem , Protetores contra Radiação/administração & dosagem , Baço/efeitos dos fármacos , Superóxido Dismutase/metabolismo
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