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1.
J Environ Manage ; 353: 120184, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38310791

RESUMO

To reduce metal pipe corrosion, improve product quality, and meet zero liquid discharge (ZLD) criteria, managing chloride ion concentrations in industrial wastewaters from metallurgical and chemical sectors has become increasingly important. This review provides detailed information on the sources, concentration levels, and deleterious effects of chloride ions in representative industrial wastewaters, and also summarizes and discusses various chloride ion removal techniques, including precipitation, ion exchange, physical separation, and advanced oxidation (AOPs). Among these, AOPs are particularly promising due to their ability to couple with other technologies and the diversity of their auxiliary technologies. The development of dechlorination electrode materials by electro-adsorption (CDI) can be inspired by the electrode materials used in chloride ion battery (CIB). This review also provides insights into exploring the effective combination of multiple chloride removal mechanisms, as well as the development of environmentally friendly composite materials. This review provides a theoretical basis and development direction for the effective treatment and secondary utilization of chlorine-containing industrial wastewater in the future.


Assuntos
Poluentes Químicos da Água , Purificação da Água , Águas Residuárias , Cloretos , Purificação da Água/métodos , Cloro , Poluentes Químicos da Água/análise , Íons
2.
Molecules ; 29(5)2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38474546

RESUMO

In this work, the assembly behavior and structure of a compound collector with different carboxyl group positions at the low-rank coal (LRC)-water interface were investigated through coarse-grained molecular dynamics simulation (CGMD) combined with sum-frequency vibration spectroscopy (SFG). The choice of compound collector was dodecane +decanoic acid (D-DA) and dodecane +2-butyl octanoic acid (D-BA). CGMD results showed that the carboxyl group at the carbon chain's middle can better control the assembly process between carboxylic acid and D molecules. SFG research found that the carboxyl group at the carbon chain's termination had a greater impact on the displacement of the methyl/methylene symmetric stretching vibration peak, while the carboxyl group at the carbon chain's middle had a greater impact on the displacement of the methyl/methylene asymmetric stretching vibration peak. The spatial angle calculation results revealed that the methyl group's orientation angle in the D-BA molecule was smaller and the carboxyl group's orientation angle in the BA molecule was bigger, indicating that D-BA spread more flatly on the LRC surface than D-DA. This meant that the assembled structure had a larger effective adsorption area on the LRC surface. The flotation studies also verified that the assembly behavior and structure of D-BA with the carboxyl group at the carbon chain's middle at the LRC-water interface were more conducive to the improvement of flotation efficiency. The study of interface assembly behavior and structure by CGMD combined with SFG is crucial for the creation of effective compound collectors.

3.
Apoptosis ; 28(3-4): 594-606, 2023 04.
Artigo em Inglês | MEDLINE | ID: mdl-36705874

RESUMO

At present, recurrence and metastasis are still important factors that lead to a poor prognosis among colorectal cancer (CRC) patients. Cancer-associated fibroblasts (CAFs) can promote tumorigenesis and development. Bufalin is the main active monomer of the clinical drug cinobufacini, which exhibits antitumor activity in various cancers. But few research have investigated the effect of bufalin in inhibiting metastasis from the perspective of the tumor microenvironment. We first isolated CAFs from freshly resected colorectal cancer patient specimens and observed the effect of CAFs on CRC cell invasion through a series of experiments. We explored the effect of bufalin on the physiological activity of CRC mediated by CAFs through experiments. In our study, we found that CAFs could promote CRC cell activity through the STAT3 pathway. Bufalin reversed CAF-mediated CRC invasion and metastasis by inhibiting the STAT3 pathway. Overexpression of STAT3 attenuated the inhibitory function of bufalin on invasion and metastasis. Taken together, bufalin can reverse CAF-mediated colorectal cancer metastasis based on inhibiting the STAT3 signaling pathway.


Assuntos
Fibroblastos Associados a Câncer , Neoplasias Colorretais , Humanos , Fibroblastos Associados a Câncer/metabolismo , Fibroblastos Associados a Câncer/patologia , Apoptose , Transdução de Sinais , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Microambiente Tumoral/fisiologia , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo
4.
Langmuir ; 39(23): 8234-8243, 2023 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-37262019

RESUMO

A microfluidic method was developed to study the ion-specific effect on bubble coalescence in salt solutions. Compared with other reported methods, microfluidics provides a more direct and accurate means of measuring bubble coalescence in salt solutions. We analyzed the coalescence time and approach velocity between bubbles and used simulation to investigate the pressure evolution during the coalescence process. The coalescence time of the three salt solutions decreased initially and then increased as the concentration of the salt solution was increased. The concentration with the shortest coalescence time is considered as the transition concentration (TC) and exhibits ion-specific. At the TC, the change in coalescence time indicates a shift in the effect of salt on bubble coalescence from facilitation to initial inhibition. Meanwhile, it can be seen that the sodium halide solutions significantly inhibit the bubble coalescence and the inhibition capability follows the order NaCl > NaBr > NaI. The results of the approach velocity show that the coalescence time decreases with increasing approach velocity, as well as the approach velocity was strongly influenced by concentration. The approach velocity undergoes a significant change at the TC. Furthermore, simulations of bubble coalescence in the microchannel indicate that the vertical pressure gradient at the center point of the bubble pairs increases as bubbles approach, driving liquid film drainage until bubble coalescence. The pressure at the center of the bubble pair reaches the maximum when the bubbles have first coalesced. It was further revealed that the concentration of the salt solution has a significant impact on the maximum pressure, as evidenced by the observed trend of decreasing pressure values with increasing concentrations.

5.
Molecules ; 28(5)2023 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-36903554

RESUMO

Chitosan (CS) is a natural and low-cost adsorbent for capturing metal ions and organic compounds. However, the high solubility of CS in acidic solution would make it difficult to recycle the adsorbent from the liquid phase. In this study, the CS/Fe3O4 was prepared via Fe3O4 nanoparticles immobilized onto a CS surface, and the DCS/Fe3O4-Cu was further fabricated after surface modification and the adsorption of Cu ions. The meticulously tailored material displayed the sub-micron size of an agglomerated structure with numerous magnetic Fe3O4 nanoparticles. During the adsorption of methyl orange (MO), the DCS/Fe3O4-Cu delivered a superior removal efficiency of 96.4% at 40 min, which is more than twice the removal efficiency of 38.7% for pristine CS/Fe3O4. At an initial MO concentration of 100 mg L-1, the DCS/Fe3O4-Cu exhibited the maximum adsorption capacity of 144.60 mg g-1. The experimental data were well explained by the pseudo-second-order model and Langmuir isotherm, suggesting the dominant monolayer adsorption. The composite adsorbent still maintained a large removal rate of 93.5% after five regeneration cycles. This work develops an effective strategy to simultaneously achieve high adsorption performance and convenient recyclability for wastewater treatment.

6.
Langmuir ; 38(8): 2467-2477, 2022 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-35179898

RESUMO

Low-rank coal (LRC) contains large amounts of harmful impurities that must be processed before utilization. Flotation is an effective means for separating fine particles, which can be influenced by air solubility in water. In this work, deaerated water (DW), ordinary water (OW), and pressurized water (PW) were prepared to research the underlying mechanism of the effect of air solubility on the flotation performance of LRC. The results show that PW dissolves the greatest amount of air in the three kinds of water (DW, OW, and PW). The flotation performance of LRC in different water types is directly proportional to air solubility in aqueous solutions. In addition, the induction time of LRC in PW (600 ms) is significantly shorter than those in OW (1200 ms) and DW (4000 ms). Atomic force microscopy (AFM) studies reveal that typical interfacial nanobubbles (NBs) only form on a highly oriented pyrolytic graphite (HOPG) surface in PW due to the supersaturated air in water. Furthermore, the interaction between LRC particles and HOPG in PW is significantly stronger than those in both OW and DW, which is attributed to the capillary force of rgw nanobubble bridge formed between particles. The hydrophobic interaction enhanced by NBs is critically important for the attachment of LRC particles to macrobubbles in flotation. Overall, air solubility in water has a great effect on LRC flotation performance, and PW flotation technology can be extended to LRC purification.

7.
Molecules ; 27(19)2022 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-36234998

RESUMO

The efficient filtration of low-rank coal (LRC) slurry was significantly beneficial to the production process of wet coal beneficiation. However, relatively few studies have been reported on novel pretreatment methods for the efficient filtration of LRC slurry. In this paper, the mechanism of ultrasonic pretreatment to promote flocculation and filtration of slurry was studied. The hydrophobic variation of the slurry surface was measured by contact angle and XPS. The flocculation properties of slurry were characterized using zeta potential and FBRM. The effects of filter cake porosity and ultrasonic pretreatment on slurry filtration resistance were calculated by L-F NMR and Darcy's theory. The results showed that the ultrasonic pretreatment promoted the flocculation and filtration performance of LRC slurry, increased the filtration rate, and decreased the cake moisture content. Meanwhile, the contact angle of LRC increased significantly from 50.1° to 67.8° after ultrasonic pretreatment, and the surface tension of the filtrate decreased from 69.5 to 53.31 mN/m. Ultrasonic pretreatment reduced the absolute value of the zeta potential of coal slurry from 24.8 to 21.0 mV, and the average chord length of flocs increased from 5-10 µm to 25-30 µm, thus weakening the electrostatic repulsion between coals to promote floc formation. In addition, the pore tests and filtration theory calculations showed that the ultrasonic pretreatment significantly improved the permeability of the filter cake to water and reduced the resistance to slurry during filtration. In particular, the mesopore porosity increased by 9.18%, and the permeability increased by 2.937 × 108 m2. Therefore, this contributed to the reduction of slurry filtration resistance. This research provides an efficient method for promoting the efficient filtration of slurry.

8.
J Am Chem Soc ; 142(16): 7317-7321, 2020 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-32248690

RESUMO

Rational design and bottom-up synthesis based on the structural topology is a promising way to obtain two-dimensional metal-organic frameworks (2D MOFs) in well-defined geometric morphology. Herein, a topology-guided bottom-up synthesis of a novel hexagonal 2D MOF nanoplate is realized. The hexagonal channels constructed via the distorted (3,4)-connected Ni2(BDC)2(DABCO) (BDC = 1,4-benzenedicarboxylic acid, DABCO = 1,4-diazabicyclo[2.2.2]octane) framework serve as the template for the specifically designed morphology. Under the inhibition and modulation of pyridine through a substitution-suppression process, the morphology can be modified from hexagonal nanorods to nanodisks and to nanoplates with controllable thickness tuned by the dosage of pyridine. Subsequent pyrolysis treatment converts the nanoplates into a N-doped Ni@carbon electrocatalyst, which exhibits a small overpotential as low as 307 mV at a current density of 10 mA cm-2 in the oxygen evolution reaction.

9.
Cancer Sci ; 111(5): 1619-1630, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32058643

RESUMO

Recent studies have shown that MDR could be induced by the high stemness of cancer cells. In a previous study, we found bufalin could reverse MDR and inhibit cancer cell stemness in colorectal cancer, but the relationship between them was unclear. Here we identified overexpressing CD133 increases levels of Akt/nuclear factor-κB signaling mediators and MDR1, while increasing cell chemoresistance. Furthermore, bufalin reverses colorectal cancer MDR by regulating cancer cell stemness through the CD133/nuclear factor-κB/MDR1 pathway in vitro and in vivo. Taken together, our results suggest that bufalin could be developed as a novel 2-pronged drug that targets CD133 and MDR1 to eradicate MDR cells and could ultimately be combined with conventional chemotherapeutic agents to improve treatment outcomes for patients with colorectal cancer.


Assuntos
Antígeno AC133/metabolismo , Antineoplásicos/farmacologia , Bufanolídeos/farmacologia , Neoplasias Colorretais/patologia , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Fator de Transcrição RelA/metabolismo , Antígeno AC133/genética , Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , Subfamília B de Transportador de Cassetes de Ligação de ATP/metabolismo , Animais , Antineoplásicos/uso terapêutico , Bufanolídeos/uso terapêutico , Linhagem Celular Tumoral , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/metabolismo , Doxorrubicina/farmacologia , Doxorrubicina/uso terapêutico , Resistência a Múltiplos Medicamentos/efeitos dos fármacos , Quimioterapia Combinada , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Camundongos , Camundongos Nus , Células-Tronco Neoplásicas/efeitos dos fármacos , Células-Tronco Neoplásicas/metabolismo , Células-Tronco Neoplásicas/patologia , Transdução de Sinais , Fator de Transcrição RelA/genética
10.
Br J Cancer ; 122(9): 1342-1353, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32203206

RESUMO

BACKGROUND: Recent studies have shown that multidrug resistance may be induced by the high stemness of cancer cells. Following prolonged chemotherapy, MDR protein 1 (MDR1) and CD133 increase in CRC, but the relationship between them is unclear. METHODS: The relationship between MDR and CSC properties in CRC was determined via CCK-8 assay, apoptosis assay, DOX uptake and retention, immunohistochemistry, immunofluorescence and flow cytometry. The correlations between their expression levels were evaluated using Spearman's rank statistical test and the Mann-Whitney test. Furthermore, the effect of CD133 on the repression of the AKT/NF-κB/MDR1 signalling pathway was investigated in vitro and in vivo. RESULTS: We found that CD133 increased with the emergence of drug-resistance phenotypes, and the high expression of MDR1/P-gp was consistently accompanied by positive expression of CD133 as demonstrated by the analysis of patient samples. Up- or downregulation of CD133 could regulate MDR via AKT/NF-κB/MDR1 signalling in CRC. A rescue experiment showed that the AKT/NF-κB signalling pathway is the main mechanism by which CD133 regulates MDR1/P-gp expression in CRC. CONCLUSIONS: Taken together, our results suggest that targeting CD133 reverses drug resistance via the AKT/NF-κB/MDR1 pathway and that this pathway might serve as a potential therapeutic target to reverse MDR in CRC.


Assuntos
Antígeno AC133/genética , Neoplasias Colorretais/tratamento farmacológico , Doxorrubicina/farmacologia , Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Neoplasias Colorretais/genética , Neoplasias Colorretais/patologia , Resistencia a Medicamentos Antineoplásicos/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , NF-kappa B/genética , Proteínas Proto-Oncogênicas c-akt/genética , Transdução de Sinais/efeitos dos fármacos , Fator de Transcrição RelA/genética
11.
Langmuir ; 36(16): 4339-4346, 2020 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-32237714

RESUMO

It is well recognized that an improved flotation recovery can be achieved by introducing nanobubbles to common flotation practice due to the increased capture efficiency between bubbles and particles. However, the specific role of nanobubbles in bubble-particle interactions (collision, attachment, and detachment) is not well understood. In the present study, we explore the role of surface nanobubbles in bubble-particle detachment. Surface nanobubbles were introduced via ethanol-water exchange and their presence was confirmed using laser scanning confocal microscopy (LSCM). The effect of surface nanobubbles on bubble-particle detachment behavior was then investigated using an oscillating bubble apparatus. Bubble-particle aggregate stability was evaluated using critical detachment amplitude. Further, bubble-particle detachment forces in the absence and presence of nanobubbles were measured directly using a micro-nano mechanical testing system. Using LSCM, numerous surface nanobubbles were observed on a glass surface after ethanol-water exchange, regardless of wettability. The number and lateral dimensions of generated nanobubbles on the hydrophilic surface were significantly smaller than that on the hydrophobic surface. Surface nanobubbles increased the stability of bubble-particle aggregates. Macroscopic air bubbles coalesce with the nanobubbles on the particle surface, increasing the pinning effect of the three-phase contact line and advancing contact angle. As a result, the capillary force between bubbles and particles increased in the presence of surface nanobubbles.

12.
Mol Ther ; 27(10): 1810-1824, 2019 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-31208913

RESUMO

Hypoxia is associated with poor prognosis and therapeutic resistance in cancer patients. Accumulating evidence has shown that microRNA (miRNA) plays an important role in the acquired drug resistance in colorectal carcinoma (CRC). However, the role of miRNA in hypoxia-induced CRC drug resistance remains to be elucidated. Here, we identified a hypoxia-triggered feedback loop that involves hypoxia-inducible transcription factor 1α (HIF-1α)-mediated repression of miR-338-5p and confers drug resistance in CRC. In this study, the unbiased miRNA array screening revealed that miR-338-5p is downregulated in both hypoxic CRC cell lines tested. Repression of miR-338-5p was required for hypoxia-induced CRC drug resistance. Furthermore, we identified interleukin-6 (IL-6), which mediates STAT3/Bcl2 activation under hypoxic conditions, as a direct miR-338-5p target. The resulting HIF-1α/miR-338-5p/IL-6 feedback loop was necessary for drug resistance in colon cancer cell lines. Using CRC patient samples, we found miR-338-5p has a negative correlation with HIF-1α and IL-6. Finally, in a xenograft model, overexpressing miR-338-5p in CRC cells and HIF-1α inhibitor PX-478 were able to enhance the sensitivity of CRC to oxaliplatin (OXA) via suppressing the HIF-1α/miR-338-5p/IL-6 feedback loop in vivo. Taken together, our results uncovered an HIF-1α/miR-338-5p/IL-6 feedback circuit that is critical in hypoxia-mediated drug resistance in CRC; targeting each member of this feedback loop could potentially reverse hypoxia-induced drug resistance in CRC.


Assuntos
Neoplasias Colorretais/patologia , Resistencia a Medicamentos Antineoplásicos , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Interleucina-6/genética , MicroRNAs/genética , Animais , Linhagem Celular Tumoral , Proliferação de Células , Sobrevivência Celular , Neoplasias Colorretais/genética , Retroalimentação Fisiológica , Regulação Neoplásica da Expressão Gênica , Células HCT116 , Humanos , Camundongos , Transplante de Neoplasias , Oxaliplatina , Prognóstico , Hipóxia Tumoral
13.
Pak J Pharm Sci ; 32(3 Special): 1441-1445, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31551229

RESUMO

Objective of the present study was to investigate the effects of peripherally inserted central catheter (PICC) parenteral nutrition support on immune function and nutritional support in patients undergoing radical gastrectomy for gastric cancer. 140 patients who underwent radical gastrectomy for gastric cancer were selected as participants and were divided into study group and the control group by random number table, with 70 cases in each group. Patients in the two groups underwent standard gastrectomy under general anesthesia by the same group of doctors. The study group received postoperative PICC catheter parenteral nutrition, and the control group received central venous catheter (CVC) nutrition support. Comparative study was done using t test and Chi-square test. The serum levels of ALB, TFN, PA, Hb, CD4+, CD8+, CD4+/CD8+, IgA, IgG, IgM and CD3+ in the two groups were observed before and after treatment, and the postoperative complications of the two groups were compared. After treatment, the levels of ALB, TFN, PA and Hb in the two groups were significantly increased (P<0.05). Levels of CD3+, CD4+, CD4+/CD8+, IgA, IgG and IgM also amplified significantly after treatment in both the groups, while CD8+ decreased significantly (P<0.05). What's more, the improvement degree of the study group was significantly greater than that of the control group (P<0.05). The time of drawing drainage tube, recovering intestinal function, getting off bed and the length of hospital stay in the study group were significantly shorter than those in the control group (P<0.05). The incidence of postoperative complications in the study group and control group were 8.6% (6/70 cases) and 11.4% (8/70 cases) respectively, and there was no significant difference (P>0.05). PICC catheter parenteral nutrition support and improve the nutritional status of patients, it was proved a safe and effective nutritional support which improve the cellular immune function and accelerated the recovery of gastrointestinal function.


Assuntos
Nutrição Parenteral/métodos , Complicações Pós-Operatórias/prevenção & controle , Neoplasias Gástricas/cirurgia , Dispositivos de Acesso Vascular , Idoso , Antígenos de Diferenciação de Linfócitos T/sangue , Cateteres Venosos Centrais , Feminino , Gastrectomia , Humanos , Isotipos de Imunoglobulinas/sangue , Masculino , Pessoa de Meia-Idade , Nutrição Parenteral/instrumentação , Complicações Pós-Operatórias/dietoterapia , Complicações Pós-Operatórias/imunologia , Resultado do Tratamento
14.
Nanotechnology ; 29(19): 195201, 2018 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-29465413

RESUMO

Transition metal sulfides are considered to be promising candidates as anodes for sodium ion batteries (SIBs). However, their further applications are limited by poor electrical conductivity and sluggish electrochemical kinetics. We report, for the first time, nickel-doped Co9S8 hollow nanoparticles as SIB anodes with enhanced electrical conductivity and a large pseudocapacitive effect, leading to fast kinetics. This compound exhibits excellent sodium storage performance, including a high capacity of 556.7 mA h g-1, a high rate capability of 2000 mA g-1 and an excellent stability up to 200 cycles. The results demonstrate that nickel-doped Co9S8 hollow nanoparticles are a promising anode material for SIBs.

15.
Phys Chem Chem Phys ; 19(36): 24421-24435, 2017 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-28869257

RESUMO

A deep understanding of the bubble-particle attachment is critical to flotation science and engineering. Historically, the so called "hydrophobic force" has been widely accepted to be the reason for bubble-particle attachment although its origin is still under debate now. In this paper, a number of representative mechanisms for the origin of hydrophobic attractions are reviewed, with the main focus being on solid-solid systems. Then we highlight the recent advances in the hydrophobic force measurement between bubble and particle. Quantitative description of the hydrophobic force in bubble-particle system has been achieved recently. This review is closed with a brief conclusion and perspective discussion.

16.
Water Sci Technol ; 76(3-4): 694-704, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28759451

RESUMO

Thermal-sensitive polymers have been tested on settling, compacting or dewatering of clays or oil sand tailings. However, not much attention has been paid to explore the effect of temperature on flocculating performance using thermal-sensitive polymers. In this study, poly(NIPAM-co-DMAPMA) was synthesized and employed to investigate the flocculating and re-flocculating performance of hydrophilic and hydrophobic particles at two specific temperatures; meanwhile settling and dewatering behaviors were also investigated. The results demonstrated that good flocculating performances were achieved at both room temperature (∼23 °C) and lower critical solution temperature (45 °C). Furthermore, larger flocs were formed at 45 °C as the copolymer was added. Floc strength and re-flocculating ability of the flocs were also intensified prominently at 45 °C. Additionally, settling and dewatering rates of suspensions were improved, and the moisture of filtered cakes was reduced when suspensions were at 45 °C. The phenomena could be justified by the phase transition of the copolymer from hydrophilicity to hydrophobicity as the temperature increased. There were much stronger adhesion forces between particles and higher adsorption amount of the copolymer onto solid surfaces at 45 °C. Therefore, the copolymer may be promising in solid-liquid separation to improve the floc size, floc strength, and settling and dewatering rate to achieve much lower moisture filtered cake.


Assuntos
Eliminação de Resíduos/métodos , Eliminação de Resíduos Líquidos/métodos , Poluentes Químicos da Água/química , Resinas Acrílicas , Adsorção , Floculação , Interações Hidrofóbicas e Hidrofílicas , Transição de Fase , Polímeros/química , Dióxido de Silício , Temperatura
17.
Water Sci Technol ; 74(3): 729-37, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27508378

RESUMO

pH-sensitive copolymers have been widely introduced to achieve rapid dewatering and consolidation of solids in mining and oil sands processing wastes. But no more attention has been given to the flocculation efficiency of solid suspensions as a function of pH using pH-sensitive copolymer. In this study, a pH-sensitive copolymer was synthesized and employed to investigate the flocculation behaviors of kaolin by focused beam reflectance measurement (FBRM). A titration test was introduced to characterize the copolymer conformation transition. The results demonstrated that at pH ranging from 3 to 6, with the pH increase, the zeta potential magnitude of kaolin particles increased, resulting in the repulsive forces between particles increasing. However, the hydrophobicity of kaolin increased as the pH increased. Thus, the hydrophobic forces could neutralize a part of the repulsive forces between particles and result in good and similar flocculation performances. At the pH greater than 6, the zeta potential magnitude of kaolin particles and copolymer molecules increased significantly, and the repulsive force between kaolin particles increased after copolymer addition due to the kaolin particles being more negatively charged, which resulted in poor flocculation efficiency and cloudy supernatant. It was concluded that the pH-sensitive copolymer could achieve both perfect flocculation efficiency and low moisture of filter cake at the isoelectric point of copolymer.


Assuntos
Caulim/química , Polímeros/química , Floculação , Concentração de Íons de Hidrogênio , Campos de Petróleo e Gás
18.
Tumour Biol ; 2015 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-26298723

RESUMO

Gastric carcinoma (GC) is a prevalent malignant cancer worldwide and is highly lethal due to its fast growth. Hence, treatments to suppress GC cell growth may be applied together with surgery and chemotherapy to increase therapeutic outcome. Previous studies have shown the involvement of some microRNAs (miRNAs or miRs) in the carcinogenesis of GC, whereas a role of miR-132 in regulating the growth of GC has not been reported. Here, we report that overexpression of miR-132 in GC cells decreased FoxO1 protein levels, whereas depletion of miR-132 increased FoxO1 protein levels, without altering FoxO1 transcripts. Bioinformatics analyses showed that miR-132 bound to 3'-untranslated region (3'-UTR) of FoxO1 messenger RNA (mRNA) to prevent its translation, which was confirmed by luciferase reporter assay. Moreover, miR-132-mediated suppression of FoxO1 in GC cells resulted in a significant increase in GC cell growth in vitro and in vivo, while increases in FoxO1 by expression of antisense of miR-132 significantly decreased GC cell growth in vitro and in vivo. Finally, miR-132 levels were found significantly increased in GC specimens, compared to those in paired non-tumor gastric tissue. Together, our data suggest that miR-132 upregulation in GC cells may promote cell growth through suppression of FoxO1 translation.

19.
Environ Technol ; 45(10): 2012-2021, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36576062

RESUMO

Increasing attention has been focused on the comprehensive utilisation of alkaline red mud (RM) derived from the aluminium industry. Phytoremediation serves as an effective strategy, but it is limited by the drawbacks of red mud. This study proposed 'co-hydrothermally treating red mud and sewage sludge (SS)' for producing a soil-like matrix, and explored the impacts of SS addition on the characteristics of hydrothermal solid and liquid products of RM. The results showed that the introduction of SS could improve the characteristics of hydrothermal products, including pH, the particle aggregation, and organic components. During hydrothermal treatment, the acid components released from SS could neutralise the alkalinity of RM, reducing the pH of hydrothermal product from 10.1 (without SS) to and 8.2 (80% SS), respectively. With the increase of addition ratio of SS, the main range of particle size distribution in hydrothermal solid products changed from 0.1∼1 µm to 10∼100 µm, suggesting the positive role of SS in improving the particle aggregation. XRD analysis showed that the addition of SS hindered the mineral crystallization of RM during hydrothermal treatment, while FTIR and XPS analysis confirmed that SS could serve as a 'supply source' of organic components, which created favourable conditions for hydrothermal solid products as soil-like matrix. The addition ratio of SS presented the negative correlation with the pH value and positive relative with chemical oxygen demand of hydrothermal liquid products. The hydrothermal liquid product modified by SS was beneficial to further improve soil-like matrix. The strategy of co-hydrothermal treating RM and SS to produce the soil-like matrix could massively consume solid wastes, which is a prospective approach to deal with the trouble of the aluminium industry and sewage treatment plants.


Assuntos
Esgotos , Solo , Esgotos/química , Solo/química , Alumínio , Biodegradação Ambiental
20.
ACS Omega ; 9(19): 21071-21081, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38764646

RESUMO

The study on the effect of fatty acid saturation on low-rank coal (LRC) flotation is still limited. In this investigation, density functional theory (DFT) combined with Zeta potential and Fourier transform infrared spectroscopy (FTIR) was used to study the mechanism of intermolecular weak interaction at the LRC-water interface of fatty acids (decanoic acid (DA), undecylenic acid (UA), and phenyl propionic acid (PA)) with different saturations and different dodecane (D) composition hydrocarbon oil-fatty acid mixed collectors (D-DA, D-UA, D-PA). The findings demonstrated that the hydrogen bond interaction and electrostatic interaction between the UA/PA with unsaturated bonded carbon chains and the LRC molecular fragments/water molecules were stronger than DA without a saturated bond carbon chain, and UA/PA strengthened its interaction with water molecules on the whole, even PA molecules would preferentially interact with water molecules. The unsaturated bond had a minimal impact on the adsorption of the LRC hydrophobic site, and the strength of the hydrogen bond between the mixed collector and LRC is D-DA > D-UA > D-PA. In the actual flotation process, the strong hydrogen bonding and electrostatic interaction between UA/PA and water molecules weaken the collection performance of the mixed collector D-UA/D-PA for LRC, which also confirmed the research results of DFT, FTIR, and Zeta.

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