One of their most recent publications is The stable blue and unstable UV photoluminescence from carbon nanoclusters embedded in SiO2 matrices. Which was published in journal Solid State Communications.

More information about Qi Zhang research including statistics on their citations can be found on their Copernicus Academic profile page.

Qi Zhang's Articles: (107)

The stable blue and unstable UV photoluminescence from carbon nanoclusters embedded in SiO2 matrices

AbstractStrong and stable blue photoluminescence (PL) from annealed C clusters embedded in SiO2 (deposited by r.f.-sputtering) was recorded, under excitation power on a scale of μW cm−2. UV PL was also recorded from about half of the annealed samples, but this was not stable — the intensity decayed with time. Carbon and oxygen K-edge XAFS (X-ray absorption fine structure) suggest that (1) the nanoclusters present are C-based materials, (2) the luminescent materials probably involve π bonded carbon. The size distributions of the nanoclusters obtained by TEM suggest that a quantum-confined size effect can also apply to the blue PL.

Label-free electrochemical immunoassay for neuron specific enolase based on 3D macroporous reduced graphene oxide/polyaniline film

AbstractThe content of neuron specific enolase (NSE) in serum is considered to be an essential indicator of small cell lung cancer (SCLC). Here, a novel label-free electrochemical immunoassay for the detection of NSE based on the three dimensionally macroporous reduced graphene oxide/polyaniline (3DM rGO/PANI) film has been proposed. The 3DM rGO/PANI film was constructed by electrochemical co-deposition of GO and aniline into the interspaces of a sacrificial silica opal template modified Au slice. During the co-deposition, GO was successfully reduced by aniline and PANI could be deposited on the surfaces of rGO sheets. The ratio of rGO and PANI in the composite was also optimized to achieve the maximum electrochemical performance. The 3DM rGO/PANI composite provided larger specific surface area for the antibody immobilization, exhibited enhanced conductivity for electron transfer, and more important was that PANI acted as the electroactive probe for indicating the NSE concentration. Under the optimal conditions, a linear current response of PANI to NSE concentration was obtained over 0.5 pg mL−1-10.0 ng mL−1 with a detection limit of 0.1 pg mL−1. Moreover, the immunosensor showed excellent selectivity, good stability, satisfactory reproducibility and regeneration, and was employed to detect NSE in clinical serum specimens.

Dynamical fluctuations in classical adiabatic processes: General description and their implications

AbstractDynamical fluctuations in classical adiabatic processes are not considered by the conventional classical adiabatic theorem. In this work a general result is derived to describe the intrinsic dynamical fluctuations in classical adiabatic processes. Interesting implications of our general result are discussed via two subtopics, namely, an intriguing adiabatic geometric phase in a dynamical model with an adiabatically moving fixed-point solution, and the possible “pollution” to Hannay’s angle or to other adiabatic phase objects for adiabatic processes involving non-fixed-point solutions.

Associated changes in HCN2 and HCN4 transcripts and If pacemaker current in myocytes

AbstractThe time- and voltage-dependent inward current generated by the hyperpolarization-activated cyclic nucleotide-gated (HCN) channels contributes to the tissue-specific rhythmic activities in the brain and heart. Four isoforms (HCN1–HCN4) have been identified. Previous studies showed that different HCN isoforms may form functional heteromeric channels. We report here that when HCN2 and HCN4 mRNA were injected into Xenopus oocytes with various ratios of HCN2 over HCN4 at 1:1, 10:1, and 1:10, respectively, the resultant channels showed a depolarized current activation and significantly faster activation kinetics near the midpoint of activation compared with HCN4 homomeric channels. In adult rat myocytes overexpressing HCN4, there was an associated increase in HCN2 mRNA. In neonatal rat myocytes in which HCN2 was knocked down, there was also a simultaneous decrease in HCN4 mRNA. Coimmunoprecipitation experiments showed that HCN2 and HCN4 channel proteins can associate with each other in adult rat ventricles. Finally, in adult myocytes overexpressing HCN4, the hyperpolarization-activated inward current activation, If, was shifted to physiological voltages from non-physiological voltages, associated with faster activation kinetics. These data suggested that different ratios of HCN2 and HCN4 transcripts overlapping in different tissues also contribute to the tissue-specific properties of If.

A-Raf and C-Raf differentially regulate mechanobiological response of osteoblasts to guide mechanical stress-induced differentiation

Highlights•ERK is preferentially activated by LMMS in OBs and contributes to differentiation.•A-Raf and C-Raf are upstream MAP3Ks of LMMS-induced ERK pathway in OBs.•A-Raf promotes OB differentiation in response to LMMS.•C-Raf involves in cell survival in response to LMMS.

Knockdown of ADAM17 inhibits cell proliferation and increases oxaliplatin sensitivity in HCT-8 colorectal cancer through EGFR-PI3K-AKT activation

Highlights•High expression of ADAM17 is associated with oxaliplatin chemosensitivity.•Chronic oxaliplatin exposure established drug-resistant cell line HCT-8/L-OHP.•Down regulation of ADAM17 can enhance sensitivity and reverse resistance to oxaliplatin.•Downregulation of ADAM17 inhibit cell proliferation, induce apoptosis via EGFR/PI3K/AKT signaling pathway.

High glucose/ox-LDL induced hepatic sinusoidal capillarization via αvβ5/FAK/ERK signaling pathway

Highlights•The first study of high glucose/oxLDL induced integrin αvβ5 mediated molecular mechanism of hepatic sinusoidal dysfunction.•First explored high glucose/oxLDL induced hepatic sinusoidal capillarization via integrin αvβ5/FAK/ERK signaling pathway in LCECs.•Providing a theoretical basis for the prevention and treatment of T2DM with fatty liver disease.

The generalized center problem of degenerate resonant singular point☆

AbstractIn this paper, generalized center condition and integrability of degenerate resonant singular point for a class of complex polynomial differential system were studied. The method was based on a homeomorphic transformation of the degenerate singular point into elementary singular point, which allows us to compute the generalized singular point quantities and determine the generalized center condition for the origin. In the end, we obtained the necessary and sufficient conditions of generalized complex center of degenerate resonant singular point.

Tailoring the interlayer interaction between doxorubicin-loaded graphene oxide nanosheets by controlling the drug content

AbstractWe experimentally and theoretically investigated the influence of a model drug, doxorubicin (DOX) on GO interlayer interaction by evaluating the pyrolysis activation energy using thermogravimetric analysis and a mathematical model. It was found that the pyrolysis activation energy of DOX-loaded GO decreased from 145.8 to 119.5 kJ/mol with DOX loading content increasing from 0 to 186.6 w/w%. Theoretical simulation showed that the reduced activation energy could be ascribed to the gradually decreased interlayer interaction with DOX molecule intercalation. This involved distorted π–π stacking originating from the enlarged interlayer distance, and partially blocked interlayer hydrogen bonding. Our study suggested the possibility of tailoring the interlayer interaction and macroscopic properties of GO composites by controlling the density of molecules on the individual sheet, and offered a better understanding of inserted molecules causing interlayer interaction changes.

Research paperWip 1 inhibits intestinal inflammation in inflammatory bowel disease

Highlights•Expression of Wip1 was markedly decreased in patients with active IBD.•Wip1 was mainly expressed on neutrophils and the expression was regulated by TNF-α.•Knock out of Wip1 in mouse aggravated colonic inflammation.•Neutrophils migration was increased after knock out of Wip1.

Identification and characterization of a novel Δ6-fatty acid desaturase gene from Rhizopus arrhizus

AbstractA cDNA sequence putatively encoding a Δ6-fatty acid desaturase was isolated from Rhizopus arrhizus using reverse transcription polymerase chain reaction and rapid amplification of cDNA ends methods. Sequence analysis indicated that this cDNA sequence had an open reading frame of 1377 bp encoding 458 amino acids of 52 kDa. The deduced amino acid sequence showed high similarity to those of fungal Δ6-fatty acid desaturases which comprised the characteristics of membrane-bound desaturases, including three conserved histidine-rich motifs and hydropathy profile. A cytochrome b5-like domain was observed at the N-terminus. To elucidate the function of this novel putative desaturase, the coding sequence was expressed heterologously in Saccharomyces cerevisiae strain INVScl. The result demonstrated that the coding product of the sequence exhibited Δ6-fatty acid desaturase activity by the accumulation of γ-linolenic acid.

Combustion parameters of gaseous epoxypropane/air in a confined vessel

AbstractWe present an ignition energy measurement system, which comprises a 5 L explosion vessel, a transient pressure measurement sub-system, and a transient temperature measurement sub-system. Through a series experiments carried out with this system, the influences of the concentration of gaseous epoxypropane on the combustion pressure and temperature and on the rate of combustion pressure rise and combustion temperature rise have been analyzed, and the results are discussed. The combustion pressure and temperature of gaseous epoxypropane/air mixtures reached their highest values at a concentration of 7% within the studied range. Variation of the ignition energy within the studied range was found to have little effect on the combustion pressure or temperature of the gaseous epoxypropane/air mixtures. However, it had a significant impact on the upper flammability limit. The variation trends in the combustion pressure and temperature and the rate of pressure rise of gaseous epoxypropane/air mixtures with volume fraction appear similar. When the volume fraction of gaseous epoxypropane lies in the range 3.5–7%, the combustion pressure and temperature and the rate of pressure rise of gaseous epoxypropane/air mixtures increase with the volume fraction, while in the range 7–30% these parameters decrease with the volume fraction. The rate of temperature rise of gaseous epoxypropane/air mixtures shows a slightly different trend. It reaches the highest value at a volume fraction of 10%. The combustion pressure and temperature of gaseous epoxypropane/air mixtures reach their highest values near the lower flammability limit, which is in marked contrast to previous results on gaseous nitromethane/air mixtures.

Full Length ArticleFlame dynamics and flammability limit of DME(30%)/LPG blended clean fuel in elongated closed pipeline under multi-factors

Highlights•A new explosion pattern region diagram is provided in the parameter space of Φ and P0.•Transition boundaries of different explosion patterns were obtained.•Stable deflagration after flame fluctuation was revealed in stable acceleration area.•The acceleration effect of unit pressure on flame velocity is increasing as P0 rises.•A novel way for predicting flammability limit of complex multi-fuel is provided.

Technical noteImprovement in nanofiber filtration by multiple thin layers of nanofiber mats

AbstractNanofiber filtration is drawing great interest nowadays because of its large surface collection area as well as low air resistance. In this study, electrospun nanofiber mats of different thicknesses were evaluated for their filter quality factors. Shorter-term electrospun fiber mats exhibited a better quality factor than those longer-term electrospun ones. Multiple thin layers of nanofiber mats to improve the filter quality of the nanofiber filters were then evaluated. Filtration test results showed that the filter made up of multiple thin layers of nanofiber mats had a filter quality factor much higher than the single thick layer nanofiber mat. Better thickness uniformity in the multi-layer structure due to stacking compensation and smaller fiber diameters in nanofibers of short-term deposition time are two possible reasons for the improvement of the filter quality.

Technical noteMicrowave assisted nanofibrous air filtration for disinfection of bioaerosols

AbstractAirborne biological agents, albeit intentionally released or naturally occurring, pose one of the biggest threats to public health and security. In this study, a microwave assisted nanofibrous air filtration system was developed to disinfect air containing airborne pathogens. Aerosolized E. coli vegetative cells and B. subtilis endospores, as benign surrogates of pathogens, were collected on nanofibrous filters and treated by microwave irradiation. Both static on-filter and dynamic in-flight tests were carried out. Results showed that E. coli cells were efficiently disinfected in both static and in-flight tests, whereas B. subtilis endospores were more resistant to this treatment. Microwave power level was found to be the major factor determining the effectiveness of disinfection. Both thermal and non-thermal effects of microwave irradiation contributed to the disinfection. Reducing flow velocity to decrease heat loss yielded higher disinfection efficiency.

Thermodynamic models for determination of the solubility of dl-malic acid in methanol plus (acetonitrile, N,N-dimethylformamide, isopropyl alcohol) binary solvent mixtures

Highlights•The solubility of dl-malic acid increased with increasing temperature.•The solubility of dl-malic acid increased with the rise of the ratio of the methanol.•The solubility data were fitted using modified Apelblat equation and λh model.•The Gibbs free energy, enthalpy and entropy were calculated by the van’t Hoff analysis.

Evaluation of the enantioselectivity of glycogen-based synergistic system with amino acid chiral ionic liquids as additives in capillary electrophoresis

Highlights•Polysaccharides-based chiral ILs synergistic systems were first established.•Two novel amino acid ILs were applied for the first time in CE enantioseparation.•A central composite design was carried out to optimize the synergistic systems.•Excellent enantiosepations were achieved for all selected drug enantiomers.

Evaluation of ionic liquids-coated carbon nanotubes modified chiral separation system with chondroitin sulfate E as chiral selector in capillary electrophoresis

Highlights•ILs and NPs have received increasing attention in separation science.•ILs-coated NPs modified chiral separation system is reported for the first time.•Significant improved separations were obtained in the ILs-CNT modified system.

Stationary solutions of SPDEs and infinite horizon BDSDEs with non-Lipschitz coefficients

AbstractWe prove a general theorem that the Lρ2(Rd;R1)⊗Lρ2(Rd;Rd)-valued solution of an infinite horizon backward doubly stochastic differential equation, if exists, gives the stationary solution of the corresponding stochastic partial differential equation. We prove the existence and uniqueness of the Lρ2(Rd;R1)⊗Lρ2(Rd;Rd)-valued solutions for backward doubly stochastic differential equations on finite and infinite horizon with linear growth without assuming Lipschitz conditions, but under the monotonicity condition. Therefore the solution of finite horizon problem gives the solution of the initial value problem of the corresponding stochastic partial differential equations, and the solution of the infinite horizon problem gives the stationary solution of the SPDEs according to our general result.

Preparation of titania nanotape array and its photocatalytic property

AbstractA TiO2 nanotape array was fabricated by a seed-induced hydrothermal method without using any template. The TiO2 nanotape with an average width of about 60 nm was grown as a columnar structure with a height of 7 μm on Ti substrate. It was highly porous and robust structure due to the formation of 3D-network among the individual nanotapes. No sodium contamination was found in this TiO2 within the detection level of the energy-dispersive X-ray (EDX) analysis. The X-ray diffraction (XRD) patterns indicate that the TiO2 nanotape array is highly crystallized anatase phase. The fabricated TiO2 nanotape array demonstrated a high photocatalytic activity: its activity was 1.41 times that of the commercial Degussa P25 in evolving CO2 from the decomposition of gaseous 2-propanol.

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