Exhaled gas detection by a novel Rh-doped CNT biosensor for prediagnosis of lung cancer: a DFT study

Lung cancer has received considerable attention in recent years due to its high mortality. The difficulty in awareness of such disease can be attributed to its strong insidiousness during the early stage. Therefore, the prognosis of lung cancer becomes significant so as to nip this disease in the bud. In this paper, the Rh-doped CNT-based biosensors were introduced to realise the diagnosis of lung cancer through detecting the exhaled gas of possible patients. The adsorption property and sensing mechanism of Rh-CNT towards two kinds of mainly typical gases of lung cancer, namely, C₆H₆ and C₆H₇N, were analysed based on density functional theory, aiming at evaluating the potential application of such material to be gas sensors. The results indicated that the Rh-CNT not only has good adsorption towards such two gases but also obvious conductivity increase when interacted with any of them, while presents insensitivity upon the common exhaled gas, CO₂. We suggest the Rh-CNT be prepared as biosensors applied in the field of lung cancer pre-diagnosis that can be used in our daily life without pain and complex clinical examination.     

The synthesis of aligned silicon nanowires under ambient atmospheric pressure

Highly ordered amorphous silicon nanowires were successfully synthesized from single crystalline silicon wafer at the pyrolysis temperature of 1050 °C under ambient atmospheric pressure. Both poly (phenylcarbyne) and nickel nitrate played important roles in the growth of silicon nanowires. The fabrication of ordered silicon nanowires was controllable and repeatable, confirmed by the experimental results. The morphology and microstructure analysis of the as-obtained samples showed the highly ordered amorphous silicon nanowires were obtained, determined by scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, and FT-infrared spectroscopy. A solid-liquid-solid growing process was proposed.     

Extractive Atmospheric Pressure Photoionization (EAPPI) Mass Spectrometry: Rapid Analysis of Chemicals in Complex Matrices

Extractive atmospheric pressure photoionization (EAPPI) mass spectrometry was designed for rapid qualitative and quantitative analysis of chemicals in complex matrices. In this method, an ultrasonic nebulization system was applied to sample extraction, nebulization, and vaporization. Mixed with a gaseous dopant, vaporized analytes were ionized through ambient photon-induced ion–molecule reactions, and were mass-analyzed by a high resolution time-of-flight mass spectrometer (TOF-MS). After careful optimization and testing with pure sample solution, EAPPI was successfully applied to the fast screening of capsules, soil, natural products, and viscous compounds. Analysis was completed within a few seconds without the need for preseparation. Moreover, the quantification capability of EAPPI for matrices was evaluated by analyzing six polycyclic aromatic hydrocarbons (PAHs) in soil. The correlation coefficients (R ² ) for standard curves of all six PAHs were above 0.99, and the detection limits were in the range of 0.16–0.34 ng/mg. In addition, EAPPI could also be used to monitor organic chemical reactions in real time.

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Enhanced thermal degradation of 2,2′-dichlorodiethyl sulfide (sulfur mustard,HD) with the presence of metal oxides

Thermal degradation of sulfur mustard (2,2′-dichlorodiethyl sulfide, HD) in the presence of metal oxide adsorbents was investigated by thermal desorption in conjunction with gas chromatography–mass spectrometry (GC-MS). Zr(OH)₄, Al₂O₃, Al₂CoO₄, MgO, CeO₂, and V₂O₅ were used as metal oxide adsorbents. Neat HD was spiked onto the metal oxides packed in glass tubes, which were kept at room temperature and then heated at moderately elevated temperatures of 100°C by a thermal desorption system. The products of thermal degradation were directly transferred and analyzed by GC-MS. 1,4-Dithiane and 1,4-oxathiane were characterized as the major products of the thermal degradation of HD in the presence of Zr(OH)₄, Al₂O₃, Al₂CoO₄, and CeO₂ adsorbents. No effective degradation was observed with MgO and V₂O₅. Of particular note is Zr(OH)₄, which extremely enhanced the thermal degradation of HD.     

Investigation on landing impact dynamic and low-gravity experiments for deep space lander

Herein symmetrical four-legged suspension lunar lander was used as the research object, the six-degree-of-freedom dynamic model was built and the model of the lunar soil friction coefficient was improved. For the low-gravity simulation on objects outside earth for future work, the law of dynamic similarity for detectors was deduced. A new method was proposed for simulating the low-gravity field on the surface of objects outside earth, which was achieved by changing initial conditions of the landing by the probe and by subsequent treatment of experimental data. The prototype tested the limitation of this method was verified. It is shown that the prototypes of detectors can be used in detectors low-gravity simulation test with this method, and equipments are simple and operationally effective. This method can be used for later lunar exploration, and low-gravity simulations on extraterrestrial objects.     

Research on true color computer generated hologram by lensless Fourier transform

Based on the theory of scalar diffraction, this paper makes research on the process of hologram reconstruction of true color calculation by lensless Fourier transform, and gives its algorithm on the basis of the angular spectrum theory as well as the instances of color image reconstruction under the red, green and blue colors wavelength. In order to eliminate the influence of color difference on the reconstructive image, this paper analyzes the causes of the color difference, and puts forward the method of interpolation reconstruction to the object information in the process of hologram reconstruction, so as to eliminate the color difference. With the advantages of computer generated holographic, the high-quality color hologram by lensless Fourier transform based on the angular spectrum theory has been realized, and the results of corresponding numerical simulation are given. The results show that the method in the paper can effectively eliminate the color difference caused by different wavelength, and the experimental results validate its feasibility.     

Synthesis and biological evaluation of lycorine derivatives as dual inhibitors of human acetylcholinesterase and butyrylcholinesterase

ABSTRACT: BACKGROUND: Alzheimer's disease (AD) is a neurologically degenerative disorder that affects more than 20 million people worldwide. The selective butyrylcholinesterase (BChE) inhibitors and bivalent cholinesterase (ChE) inhibitors represent new treatments for AD. FINDINGS: A series of lycorine derivatives (1--10) were synthesized and evaluated for anti-cholinesterase activity. Result showed that the novel compound 2-O-tert-butyldimethylsilyl-1-O-(methylthio)methyllycorine (7) was a dual inhibitor of human acetylcholinesterase (hAChE) and butyrylcholinesterase (hBChE) with IC50 values of 11.40 [PLUS-MINUS SIGN] 0.66 muM and 4.17 [PLUS-MINUS SIGN] 0.29 muM, respectively. The structure-activity relationships indicated that (i) the 1-O-(methylthio)methyl substituent in lycorine was better than the 1-O-acetyl group for the inhibition of cholinesterase; (ii) the acylated or etherified derivatives of lycorine and lycorin-2-one were more potent against hBChE than hAChE; and (iii) the oxidation of lycorine at C-2 decreases the activity. CONCLUSION: Acylated or etherified derivatives of lycorine are potential dual inhibitors of hBChE and hAChE. Hence, further study on the modification of lycorine for ChE inhibition is necessary.     

Self-supported interconnected Pt nanoassemblies as highly stable electrocatalysts for low-temperature fuel cells

In it for the long haul: Clusters of Pt nanowires (3D Pt nanoassemblies, Pt?NA) serve as an electrocatalyst for low-temperature fuel cells. These Pt nanoassemblies exhibit remarkably high stability following thousands of voltage cycles and good catalytic activity, when compared with a commercial Pt?catalyst and 20?%?wt Pt?catalyst supported on carbon black (20?% Pt/CB).     

A polar corundum oxide displaying weak ferromagnetism at room temperature

Combining long-range magnetic order with polarity in the same structure is a prerequisite for the design of (magnetoelectric) multiferroic materials. There are now several demonstrated strategies to achieve this goal, but retaining magnetic order above room temperature remains a difficult target. Iron oxides in the +3 oxidation state have high magnetic ordering temperatures due to the size of the coupled moments. Here we prepare and characterize ScFeO(3) (SFO), which under pressure and in strain-stabilized thin films adopts a polar variant of the corundum structure, one of the archetypal binary oxide structures. Polar corundum ScFeO(3) has a weak ferromagnetic ground state below 356 K-this is in contrast to the purely antiferromagnetic ground state adopted by the well-studied ferroelectric BiFeO(3).