Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 21
Filter
Add more filters










Publication year range
1.
ACS Omega ; 9(18): 19992-20002, 2024 May 07.
Article in English | MEDLINE | ID: mdl-38737091

ABSTRACT

The technology of water plugging and increasing production in high water cut reservoirs of low permeability is a common problem in the industry. Epoxy resin, displaying excellent mechanical properties and adherent performance, can easily inject a tiny crack, forming a long-term blocking barrier. This study aimed to investigate an easily injectable degradable epoxy resin sealing material. The injectable performance, long-term stability, and mechanical and plugging properties were comparatively analyzed in the fractured core, and the degradable performance was discussed in the degrading solution. The result showed that the range of R (R is the ratio of EOG and MHHPA) from 1 to 1.1 and the mass fraction range of EMI from 0.01 to 4 wt % are the optimal formulations (EOGM). The curing time from 1 to 12 h could be regulated by adjusting the dosage of EMI, as well as the strength being more than 60 MPa. The plugging agent's initial viscosity is lower than 100 MPa s at 20 °C and injecting pressure is lower than 0.1 MPa. After curing for 24 h, compressive strength was more than 72.76 MPa, 3.6 times higher than that of cement, and the adhesion strength was 4.41 MPa when the contact area was 75.93 cm3. Breakthrough pressures for sealing 1-5 mm fractures were all more than 10 MPa, and the breakthrough pressure for 1 mm crack even reached 29.4 MPa. Epoxy resin/acid anhydride system could be degraded in a mixed solution of phenol-potassium salt-heavy aromatics within 7 days at 60-100 °C, which reduced the plugging well risk of the epoxy resin plugging agent. These results suggest that an epoxy resin/acid anhydride plugging agent can be employed effectively and safely for the injection of tiny cracks, which is of great engineering significance.

2.
Waste Manag ; 184: 82-91, 2024 Jul 15.
Article in English | MEDLINE | ID: mdl-38797126

ABSTRACT

Magnetic iron concentrate (MIC) and nonmagnetic tailings (NT) are obtained from magnetization roasting of iron tailings (IT). MIC containing Pb adversely affects blast furnace ironmaking, while Cu in NT poses leaching risks. This study utilizes fast pyrolysis-suspension magnetization roasting to recover iron from IT. The enrichment of Pb, Cu, and the phase transformation mechanism of Cu in the process of suspension magnetization roasting and magnetic separation were clarified. Results show 96.13 % of Cu in IT is in limonite and 47.23 % of Pb is associated with iron. At 750 °C, with 10 % dosage of biomass pyrolysis and 10 min roasting, Pb, Cu and Fe contents in MIC are 0.96, 2.14 and 3.17 times that of NT. Increasing roasting temperature enhances Cu associated with iron enrichment into the MIC, while oxidation of free copper oxide associated with iron forms magnetic copper ferrite. Increased pyrolyzed biomass leads to over-reduction of magnetite associated with Cu to FeO associated with Cu, promoting magnetic copper ferrite decomposition into FeO and free copper oxide. This research holds significant importance in controlling the quality of MIC and the storage risk of IT, and provides theoretical guidance for the regulation and recovery of valuable metals in subsequent processes.


Subject(s)
Copper , Iron , Lead , Copper/chemistry , Iron/chemistry , Lead/chemistry , Magnetics , Magnetic Phenomena
3.
J Enzyme Inhib Med Chem ; 39(1): 2296695, 2024 Dec.
Article in English | MEDLINE | ID: mdl-38111311

ABSTRACT

Photodynamic therapy (PDT) has been demonstrated to provide immediate relief of oesophageal cancer patients' re-obstruction and extend their lifespan. However, tumour regrowth may occur after PDT due to enhanced aerobic glycolysis. Previous research has confirmed the inhibitory effect of Dihydroartemisinin (DHA) on aerobic glycolysis. Therefore, the current study intends to investigate the function and molecular mechanism of DHA targeting tumour cell aerobic glycolysis in synergia PDT. The combined treatment significantly suppressed glycolysis in vitro and in vivo compared to either monotherapy. Exploration of the mechanism through corresponding experiments revealed that pyruvate kinase M2 (PKM2) was downregulated in treated cells, whereas overexpression of PKM2 nullified the inhibitory effects of DHA and PDT. This study proposes a novel therapeutic strategy for oesophageal cancer through DHA-synergized PDT treatment, targeting inhibit PKM2 to reduce tumour cell proliferation and metastasis.


Subject(s)
Esophageal Neoplasms , Photochemotherapy , Humans , Cell Line, Tumor , Cell Proliferation , Esophageal Neoplasms/drug therapy , Esophageal Neoplasms/pathology , Glycolysis , Pyruvate Kinase/metabolism
4.
Phys Chem Chem Phys ; 25(32): 21456-21467, 2023 Aug 16.
Article in English | MEDLINE | ID: mdl-37539623

ABSTRACT

Based on cylindrical photonic crystals in one dimension, a multi-scale sensor device with a logic operation is being proposed. At the same time, it can satisfy the functions of refractive index (RI) and magnetic field detection. Under the modulation of an external magnetic field, sharp absorption peaks (APs) are obtained in the terahertz (THz) range. In a certain frequency range (AP value above 0.9), as the particular InSb layers are applied to two different magnetic fields, APs of the same frequency can be implemented to operate as XOR logic gates. The results show that with a change in the detected physical quantity, the frequency point of the corresponding AP also moves. Therefore, by adjusting the position of the AP, the magnetic field and RI can be sensed, and the device shows relatively excellent performance of 6879.88 and 6943.65 in terms of quality factor. In addition, the optimal performance of sensitivity, detection limit, and corresponding figure of merit is 0.01264(2πc/d0) T-1, 2.25 × 10-4 T, 227.23 T-1, and -0.003779(2πc/d0) RIU-1, 7.69 × 10-3 RIU, 67.74 RIU-1. In terms of overall sensors, the proposed device is highly innovative in structure and meets the requirements of multi-scale measurements.

5.
Hernia ; 27(4): 969-977, 2023 08.
Article in English | MEDLINE | ID: mdl-36808493

ABSTRACT

PURPOSE: We conducted this study to investigate the efficacy, safety, and clinical value of postoperative compression in preventing seroma formation, relieving acute pain, and improving QoL after groin hernia repair. METHODS: This multi-center, prospective, observational real-world study was conducted from March 1, 2022, to August 31, 2022. The study was completed in 53 hospitals in 25 provinces in China. A total of 497 patients who underwent groin hernia repair were enrolled. All patients used a compression device to compress the operative region after surgery. The primary outcome was seroma incidence 1 month after surgery. Secondary outcomes included postoperative acute pain and QoL. RESULTS: A total of 497 patients [median (IQR) age 55 (41-67) years, 456 (91.8%) male] were enrolled, of whom 454 underwent laparoscopic groin hernia repair and 43 open hernia repair. The follow-up rate was 98.4% 1 month after surgery. Seroma incidence was 7.2% (35 of 489 patients) overall, lower than reported by previous research. No significant differences were found between the two groups (P > 0.05). VAS scores after compression were significantly lower than before compression overall and in both groups (P < 0.001). The laparoscopic group showed a high level of QoL compared with the open group, but there was no significant difference between the two groups (P > 0.05). CCS score correlated positively with VAS score. CONCLUSION: Postoperative compression, to a certain extent, can reduce seroma incidence, relieve postoperative acute pain, and improve QoL after groin hernia repair. Further large-scale randomized controlled studies are warranted to determine long-term outcomes.


Subject(s)
Acute Pain , Hernia, Inguinal , Laparoscopy , Humans , Male , Middle Aged , Female , Herniorrhaphy/adverse effects , Acute Pain/complications , Acute Pain/surgery , Seroma/etiology , Seroma/prevention & control , Quality of Life , Groin/surgery , Prospective Studies , Surgical Mesh/adverse effects , Laparoscopy/adverse effects , Pain, Postoperative/etiology , Pain, Postoperative/prevention & control , Pain, Postoperative/surgery , Hernia, Inguinal/surgery , Hernia, Inguinal/complications , Postoperative Complications/etiology , Postoperative Complications/prevention & control , Postoperative Complications/surgery
6.
Waste Manag ; 156: 255-263, 2023 Feb 01.
Article in English | MEDLINE | ID: mdl-36508909

ABSTRACT

A major industrial solid waste, iron tailings occupy a large area and pose long-term pollution risks. The pyrolysis gas of biomass was used as reducing agent to suspension magnetize and roast iron tailings to recover iron in this study. The process conditions, phase transformation and microstructure evolution of the iron tailings, pyrolysis gas production, and reaction regulations were investigated to explain the mechanism of iron recovery by suspension magnetization roasting (SMR) under the action of biomass pyrolysis gas. These studies were conducted using X-ray diffraction, scanning electron microscopy, vibrating sample magnetometer, thermo-gravimetric and differential scanning calorimetry, brunauer-emmett-teller specific surface area, and gas chromatography. The results showed that, after the grinding-magnetic separation process, the iron recovery rate was 93.32 %; the iron grade of the iron concentrate was 61.50 %. The optimal process conditions were determined as follows: fast pyrolysis temperature of 600 °C, SMR temperature of 700 °C, biomass dosage of 10 %, and SMR time of 4-5 min. The formation of Fe3O4 from the surface to the interior of the particles during the reduction process, and formation of pores and cracks led to an increase in the specific surface area. The SMR temperature not only improved the heat and mass transfer effect in the reduction process but also generated more CO and H2 through the reverse reaction of methanation, which work together to increase the saturation magnetisation of the unit sample. This method can be used to efficiently recover high quality iron from refractory iron ores.


Subject(s)
Iron , Pyrolysis , Biomass , Iron/chemistry , Thermogravimetry , Magnetics , Industrial Waste/analysis
7.
Fish Physiol Biochem ; 48(5): 1377-1387, 2022 Oct.
Article in English | MEDLINE | ID: mdl-36136164

ABSTRACT

Insulin-like growth factor 3 plays an important role in gonad development in teleost fish. Previous studies found that igf3 was specifically expressed in gonads of silver pomfret (Pampus argenteus). Unlike in other fish, IGF3 is a membrane protein in silver pomfret, and its specific role in gonads is unclear. Herein, we explored the importance of IGF3 in oogenesis and spermatogenesis in silver pomfret by analyzing gene expression and cellular localization. During follicular development, igf3 was detected in ovaries at both mRNA and protein levels during the critical stages of vitellogenesis (IV-VI). Localization analysis detected igf3 mRNA and protein in somatic cells, including theca and granulosa cells around oocytes. Similar to cathepsin L and cathepsin K, igf3 was consistently expressed in ovaries during vitellogenesis, suggesting that it might play a key role in vitellogenesis of oocytes. During spermatogenesis, igf3 mRNA and protein levels were high in stages II, IV, and V, similar to sycp3 and dmc1, and the highest igf3 mRNA and protein levels were reached in stage VI. Furthermore, igf3 mRNA and protein were detected in spermatogonia, spermatocytes, spermatids, and surrounding Sertoli cells, but not in spermatozoon, indicating that IGF3 might be involved in differentiation and meiosis of spermatogonia.


Subject(s)
Perciformes , Somatomedins , Male , Female , Animals , Cathepsin L/metabolism , Cathepsin K/metabolism , Seasons , Somatomedins/genetics , Somatomedins/metabolism , Gonads/metabolism , Perciformes/genetics , Perciformes/metabolism , RNA, Messenger/genetics , RNA, Messenger/metabolism , Fishes/metabolism , Membrane Proteins/metabolism
8.
Molecules ; 27(11)2022 May 27.
Article in English | MEDLINE | ID: mdl-35684395

ABSTRACT

This study investigated the effects of microwave modification, alkali polyphenol (ferulic acid) covalently combined modification, and microwave-alkali polyphenol covalently combined modification on the gel properties of soy protein emulsions. The results showed that the properties of soy protein emulsions were improved significantly by the three modification methods. After three kinds of modification, the viscoelasticity of soy protein emulsion gel increased, and a gel system with stronger elasticity was formed. The texture, water-holding, and hydration properties of the emulsion gel increased significantly. The SEM and ClSM results showed that the modified soy protein emulsion gel had a more compact and uniform porous structure, and the oil droplets could be better embedded in the network structure of the gel. Among the three modification methods, the microwave-alkali method polyphenol covalently combining the compound modification effect was best, and the microwave modification effect was least effective compared to the other two methods. Our obtained results suggested that for gel property modification of soy protein emulsion gels, microwave pretreatment combined with the covalent binding of polyphenols by an alkaline method is an effective method.


Subject(s)
Polyphenols , Soybean Proteins , Emulsions/chemistry , Gels/chemistry , Microwaves , Soybean Proteins/chemistry , Water/chemistry
9.
Biochem Biophys Res Commun ; 604: 88-95, 2022 05 14.
Article in English | MEDLINE | ID: mdl-35303684

ABSTRACT

Circular RNAs (circRNAs), characterized as single-stranded closed circular RNA molecules, have been established to exert pivotal functions in various biological or pathological processes. Nonetheless, the effects and underlying mechanisms concerning circRNAs on the aging and aging-related diseases remain elusive. We herein compared the expression patterns of circRNAs in young and senescent mouse embryonic fibroblasts (MEFs), and uncovered that circRNF169 was dramatically up-regulated in senescent MEFs compared with that in young MEFs. Therefore, we further digged into the role and potential mechanisms of circRNF169 in the senescence of MEFs. The results of senescence-associate-ß-galactosidase staining and BrdU incorporation assay showed that silencing of circRNF169 significantly delayed MEFs senescence and promoted cell proliferation, while ectopic expression of circRNF169 exhibited the opposite effects. Moreover, the dual-luciferase reporter assay confirmed that circRNF169 acted as an endogenous miR-30c-5p sponge, which accelerated cellular senescence by sequestering and inhibiting miR-30c-5p activity. Taken together, our results suggested that circRNF169 exerted a crucial role in cellular senescence through sponging miR-30c-5p and represented a promising target for aging intervention.


Subject(s)
Cellular Senescence , MicroRNAs , RNA, Circular , Animals , Cell Proliferation/genetics , Cellular Senescence/genetics , Fibroblasts/metabolism , Mice , MicroRNAs/genetics , MicroRNAs/physiology , RNA, Circular/genetics , RNA, Circular/physiology
10.
Fish Shellfish Immunol ; 121: 351-361, 2022 Feb.
Article in English | MEDLINE | ID: mdl-35033668

ABSTRACT

Temperature is a major environmental factor influence fish growth, development, metabolism and physiological performance. Silver pomfret (Pampus argenteus) is an economically important fishery species, however, the molecular mechanisms responsive to long-term cold stress are still unclear. Hence, we altered water temperature from 13 °C to 8 °C, a logistic fit curve for the survival rate of P. argenteus under a gradient cold stress were thus achieved, 50% survival rate at a measured temperature of 7 °C-7.5 °C. After stimulation, the gill, liver and muscle tissues were investigated through transcriptome, antioxidant enzymes and histological observation. The results showed that antioxidant enzyme and Na+-k+ ATPase activity in gill tissue was significantly increased, tissue damage and apoptosis were observed in multi-tissues. By high-throughput sequencing, a total of 618,097,404 reads of raw data and 598,855,490 reads of clean data were obtained, containing 12,489 differently expressed genes (DEGs). KEGG pathway enrichment analysis showed that DNA replication, protein digestion and absorption, cardiac muscle contraction, adrenergic signaling in cardiomyocytes, and metabolic pathways were significantly enriched in multi-tissues. Fifteen DEGs were selected for real-time PCR (RT-qPCR) analysis, and the results were consistent with transcriptome profiling. Based on the results, we inferred that P. argenteus survived at low temperatures may be achieved by improving the ability to scavenge oxyradical substance and enhancing cell fluidity. This present study indicated that the effects of long-term cold stress on P. argenteus, which is valuable for breeding cold-tolerant P. argenteus stocks for cultivation.


Subject(s)
Antioxidants/metabolism , Cold-Shock Response , Perciformes , Transcriptome , Animals , Cold Temperature , Gene Expression Profiling , Perciformes/genetics
11.
J Hazard Mater ; 371: 123-129, 2019 06 05.
Article in English | MEDLINE | ID: mdl-30849566

ABSTRACT

A seaweed-templated pathway was developed for the controllable synthesis of SnO2/carbon aerogel for the simultaneous removal of Hg0 and H2S in natural gases, where the SnO2 nanoparticles with an outer diameter of 4-20 nm were highly dispersed and conjoined by graphitic carbon, forming a 3D core-shell structure with a developed pore network. The synthesized sorbent performed a complete removal of Hg0 and H2S at a high space velocity of 70,000 h-1 and showed resistance to water. At 5% breakthrough, the Hg0 and H2S capture capacities reached as high as 10.37 mg g-1 and 392.23 mg g-1, respectively, which are much higher than those of the existing commercial sorbents. More importantly, the spent sorbent could be easily regenerated without significant performance degradation over five cycles. The 3D interconnected macro- and mesopores are beneficial for the Hg0 and H2S removal at a high space velocity, and the core-shell structure is conducive to prevent poisoning from water. The Hg0 and H2S removal over the SnO2/aerogel conforms to the E-R mechanism, where H2S is first adsorbed and dissociated on the SnO2 surface to produce active sulfur species, and the adsorbed sulfur then reacts with gaseous Hg0 to form HgS.

12.
Front Psychol ; 8: 1468, 2017.
Article in English | MEDLINE | ID: mdl-28900409

ABSTRACT

Evaluative conditioning (EC) procedures can be used to form and change attitudes toward a wide variety of objects. The current study examined the effects of a negative EC procedure on attitudes toward chocolate, and whether it influenced chocolate evaluation and consumption. Participants were randomly assigned to the experimental condition in which chocolate images were paired with negative stimuli, or the control condition in which chocolate images were randomly paired with positive stimuli (50%) and negative stimuli (50%). Explicit and implicit attitudes toward chocolate images were collected. During an ostensible taste test, chocolate evaluation and consumption were assessed. Results revealed that compared to participants in the control condition, participants in the experimental condition showed more negative explicit and implicit attitudes toward chocolate images and evaluated chocolate more negatively during the taste test. However, chocolate consumption did not differ between experimental and control conditions. These findings suggest that pairing chocolate with negative stimuli can influence attitudes toward chocolate, though behavioral effects are absent. Intervention applications of EC provide avenues for future research and practices.

13.
J Control Release ; 229: 183-191, 2016 05 10.
Article in English | MEDLINE | ID: mdl-27016140

ABSTRACT

Functional nanocarriers capable of transporting high drug contents without premature leakage and to controllably deliver several drugs are needed for better cancer treatments. To address this clinical need, gold cluster bovine serum albumin (AuNC@BSA) nanogates were engineered on mesoporous silica nanoparticles (MSN) for high drug loadings and co-delivery of two different anticancer drugs. The first drug, gemcitabine (GEM, 40wt%), was loaded in positively-charged ammonium-functionalized MSN (MSN-NH3(+)). The second drug, doxorubicin (DOX, 32wt%), was bound with negatively-charged AuNC@BSA electrostatically-attached onto MSN-NH3(+), affording highly loaded pH-responsive MSN-AuNC@BSA nanocarriers. The co-delivery of DOX and GEM was achieved for the first time via an inorganic nanocarrier, possessing a zero-premature leakage behavior as well as drug loading capacities seven times higher than polymersome NPs. Besides, unlike the majority of strategies used to cap the pores of MSN, AuNC@BSA nanogates are biotools and were applied for targeted red nuclear staining and in-vivo tumor imaging. The straightforward non-covalent combination of MSN and gold-protein cluster bioconjugates thus leads to a simple, yet multifunctional nanotheranostic for the next generation of cancer treatments.


Subject(s)
Drug Carriers/administration & dosage , Gold/administration & dosage , Nanocomposites/administration & dosage , Nanoparticles/administration & dosage , Serum Albumin, Bovine/administration & dosage , Silicon Dioxide/administration & dosage , A549 Cells , Antineoplastic Agents/administration & dosage , Antineoplastic Agents/chemistry , Cell Line , Deoxycytidine/administration & dosage , Deoxycytidine/analogs & derivatives , Deoxycytidine/chemistry , Doxorubicin/administration & dosage , Doxorubicin/chemistry , Drug Carriers/chemistry , Drug Liberation , Gold/chemistry , Humans , Nanocomposites/chemistry , Nanoparticles/chemistry , Neoplasms/diagnostic imaging , Neoplasms/drug therapy , Porosity , Serum Albumin, Bovine/chemistry , Silicon Dioxide/chemistry , Gemcitabine
14.
Int J Mol Sci ; 16(8): 18283-92, 2015 Aug 06.
Article in English | MEDLINE | ID: mdl-26287162

ABSTRACT

Polydopamine-coated FeCo nanocubes (PDFCs) were successfully synthesized and tested under microwave irradiation of 2.45 GHz frequency and 0.86 W/cm(2) power. These particles were found to be non-toxic in the absence of irradiation, but gained significant toxicity upon irradiation. Interestingly, no increase in relative heating rate was observed when the PDFCs were irradiated in solution, eliminating nanoparticle (NP)-induced thermal ablation as the source of toxicity. Based on these studies, we propose that microwave-induced redox processes generate the observed toxicity.


Subject(s)
Indoles/chemistry , Magnetite Nanoparticles/chemistry , Microwaves/adverse effects , Polymers/chemistry , Biocompatible Materials , HeLa Cells , Humans , Magnetite Nanoparticles/ultrastructure , Materials Testing , Oxidation-Reduction
15.
ACS Appl Mater Interfaces ; 7(8): 4589-94, 2015 Mar 04.
Article in English | MEDLINE | ID: mdl-25658750

ABSTRACT

Uranyl (UO2(2+)) is a form of uranium in aqueous solution that represents the greatest risk to human health because of its bioavailability. Different sensing techniques have been used with very sensitive detection limits especially the recently reported uranyl-specific DNAzymes systems. However, to the best of our knowledge, few efficient detection methods have been reported for uranyl sensing in seawater. Herein, gold nanoclusters (AuNCs) are employed in an efficient spectroscopic method to detect uranyl ion (UO2(2+)) with a detection limit of 1.86 µM. In the absence of UO2(2+), the BSA-stabilized AuNCs (BSA-AuNCs) showed an intrinsic peroxidase-like activity. In the presence of UO2(2+), this activity can be efficiently restrained. The preliminary quenching mechanism and selectivity of UO2(2+) was also investigated and compared with other ions. This design strategy could be useful in understanding the binding affinity of protein-stabilized AuNCs to UO2(2+) and consequently prompt the recycling of UO2(2+) from seawater.


Subject(s)
Biomimetic Materials/metabolism , Colorimetry , Seawater/chemistry , Uranium/analysis , Animals , Biomimetic Materials/chemistry , Cattle , Gold/chemistry , Ions/chemistry , Metal Nanoparticles/chemistry , Metals/chemistry , Organometallic Compounds/analysis , Peroxidase/metabolism , Serum Albumin, Bovine/chemistry , Serum Albumin, Bovine/metabolism
16.
Org Biomol Chem ; 12(29): 5477-83, 2014 Aug 07.
Article in English | MEDLINE | ID: mdl-24943054

ABSTRACT

An efficient and divergent one-pot synthesis of 2,3-dihydro-1H-pyrroles, 3-alkyl-1H-pyrroles and 3-alkenyl-1H-pyrroles from readily accessible 2,4-pentadienenitriles with isocyanide based on reaction condition selection has been described. The reaction of 2,4-pentadienenitriles with ethyl isocyanoacetate undergoes a formal [2 + 3] annulation either to generate 2,3-dihydro-1H-pyrroles in the presence of DBU (0.3 equiv.) in EtOH at room temperature or to give 3-alkyl-1H-pyrroles in the presence of DBU (2.0 equiv.) in EtOH under reflux. Moreover, the 2,3-dihydro-1H-pyrroles could be converted to 3-alkenyl-1H-pyrroles with DDQ as an oxidant.


Subject(s)
Cyanides/chemical synthesis , Nitriles/chemistry , Pyrroles/chemical synthesis , Acetates/chemistry , Alkenes/chemical synthesis , Alkenes/chemistry , Cyanides/chemistry , Electrons , Molecular Conformation , Pyrroles/chemistry
17.
Anal Chem ; 86(10): 4989-94, 2014 May 20.
Article in English | MEDLINE | ID: mdl-24785707

ABSTRACT

Depletion of intracellular antioxidants is linked to major cytotoxic events and cellular disorders, such as oxidative stress and multiple sclerosis. In addition to medical diagnosis, determining the concentration of antioxidants in foodstuffs, food preservatives, and cosmetics has proved to be very vital. Gold nanoclusters (Au-NCs) have a core size below 2 nm and contain several metal atoms. They have interesting photophysical properties, are readily functionalized, and are safe to use in various biomedical applications. Herein, a simple and quantitative spectroscopic method based on Au-NCs is developed to detect and image antioxidants such as ascorbic acid. The sensing mechanism is based on the fact that antioxidants can protect the fluorescence of Au-NCs against quenching by highly reactive oxygen species. Our method shows great accuracy when employed to detect the total antioxidant capacity in commercial fruit juice. Moreover, confocal fluorescence microscopy images of HeLa cells show that this approach can be successfully used to image antioxidant levels in living cells. Finally, the potential application of this "light-on" detection method in multiple logic gate fabrication was discussed using the fluorescence intensity of Au-NCs as output.


Subject(s)
Antioxidants/chemistry , Gold/chemistry , Metal Nanoparticles/chemistry , Antioxidants/radiation effects , Gold/radiation effects , HeLa Cells , Humans , Light , Metal Nanoparticles/radiation effects , Particle Size
18.
Chem Commun (Camb) ; 49(66): 7358-60, 2013 Aug 25.
Article in English | MEDLINE | ID: mdl-23852278

ABSTRACT

A facile and efficient one-pot synthesis of ß-hydroxy-γ-lactams from α,α-dialkyl ß-oxo amides and trimethylsulfoxonium iodide in the presence of sodium hydride via a tandem Corey-Chaykovsky reaction and an intramolecular lactamization process is developed.


Subject(s)
Amides/chemistry , Sulfonium Compounds/chemistry , beta-Lactams/chemical synthesis , Sodium Compounds/chemistry , beta-Lactams/chemistry
19.
Org Lett ; 15(4): 776-9, 2013 Feb 15.
Article in English | MEDLINE | ID: mdl-23391000

ABSTRACT

A facile and efficient synthesis of substituted indeno[2,1-c]quinolin-6(7H)-ones from a variety of α-acyl N-arylcinnamamides mediated by polyphosphoric acid (PPA) is described, and a mechanism involving the formation of a dicationic superelectrophile and subsequent double intramolecular nucleophilic cyclization reactions is proposed.


Subject(s)
Heterocyclic Compounds, 4 or More Rings/chemical synthesis , Indenes/chemical synthesis , Phosphoric Acids/chemistry , Polymers/chemistry , Quinolones/chemical synthesis , Catalysis , Cyclization , Heterocyclic Compounds, 4 or More Rings/chemistry , Indenes/chemistry , Molecular Structure , Quinolones/chemistry , Stereoisomerism
20.
J Org Chem ; 76(8): 2880-3, 2011 Apr 15.
Article in English | MEDLINE | ID: mdl-21391701

ABSTRACT

A facile one-pot synthesis of pyrimidin-4(3H)-ones was developed via reactions of a series of readily available 3-aminopropenamides with varied Vilsmeier reagents, and a mechanism involving sequential halogenation, formylation, and intramolecular nucleophilic cyclization is proposed.


Subject(s)
Pyrimidinones/chemical synthesis , Alkenes/chemistry , Amides/chemistry , Cyclization , Halogens/chemistry , Molecular Structure , Stereoisomerism
SELECTION OF CITATIONS
SEARCH DETAIL
...