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Glow discharge ionization source can be used to analyze solid sample, liquid sample and gas sample. At present, glow discharge optical emission spectrometer (GD-OES) and glow discharge mass spectrometer (GD-MS) are mainly used to the elemental analysis of inorganic solid samples and quantitative depth profile analysis, including direct current (DC) power supply and radio frequency (RF) power supply. In this paper, the ionization of liquid sample and gas sample by low frequency radio frequency glow discharge (Lf-RFGD) was researched, and the glow discharge structure constructed was connected to timeof flight mass spectrometer(TOF MS). The influences of the vacuum degree of ionization chamber, the size of sample inlet capillary, the auxiliary gas pressure, the discharge radio frequency and the voltage difference between electrode plates on the ionization efficiency were studied. The optimal analysis conditions are the vacuum degree of ionization chamber is about 30 Pa, the length of sample inlet capillary is 150 mm and the inner diameter is 0.25 mm, the auxiliary gas pressure is about1.0 MPa, the low discharge frequency is 2 MHz, the voltage difference between electrode plates is about 100 V. Under these conditions, the discharge power is about 20 W,the detection limit of liquid sample is 0.1 pg and volatile sample is 20 mg/m3, and the detection resolution (full width at half maximum, FWHM) is about 3 000. Combined with samples testing, the Lf-RFGD TOF MS was preliminarily applied to the drug solution and volatile organic compounds (VOCs). However, the sensitivity of this instrument for detecting non volatile liquid sample was not good compared with the conventional detection instrument. The reason is that high proton affinity and low ionization potential are needed to obtain good detection sensitivity in the positive ion mode of mass spectrometer, and non volatile liquid sample without pretreatment is not easy to meet the condition of high proton affinity under low power glow discharge condition. Successfully, a lowcost, portable approach based on the application of atmospheric sampling Lf-RFGD TOF MS has been developed for near real time measurement of trace VOCs. In this context, the glow discharge excitation source offers attractive alternative for development of low cost VOCs and elemental analysis instrument. Lf-RFGD as an excitation source has unique advantages with respect to development of hand held instrument such as low cost, low power consumption, and analytical versatility.

Objective: In order to resolve a lot of redundant information and low precision of apple internal quality evaluation existed in apple near infrared spectroscopy, improving the precision of apple internal quality evaluation. Methods: A new apple inner quality evaluation model based on deep belief network （DBN） and grey wolf optimization algorithm was proposed. According to the characteristic of high dimension and complexity of apple spectral data, the method of selecting characteristic wavelengths of apple spectral data was determined by comparing the results of selecting characteristic wavelengths of full-band, principal component analysis and continuous projection. The parameters of DBN model were optimized by GWO Algorithm, and a continuous projection method for feature wavelength selection and GWO-DBN model for apple inner quality evaluation were proposed. Results: Compared with PSO-DBN, GA-DBN and DBN, the accuracy of apple inner quality evaluation based on GWO-DBN was the highest. Conclusion: This algorithm can effectively improve the accuracy of apple inner quality evaluation and provide a new method for apple inner quality evaluation.

C40H28N4O10Co, monoclinic, C2/c (no. 15), a = 29.686(3) Å, b = 6.2315(4) Å, c = 21.0994(15) Å, β = 114.727(8)°, V = 3545.3(5) Å3, Z = 4, Rgt(F) = 0.0386, wRref(F2) = 0.0897, T = 293(2) K.

Background: Epilepsy is a chronic, complex, unprovoked, and recurrent disorder of the nervous system that affected several people worldwide. Phyllanthus amarus (PA) has been documented to have neuroprotective potential. Aim: To evaluate the potential of standardized extract of PA and its possible mechanism of action against the Pentylenetetrazol (PTZ)-induced convulsion and kindling associated post-ictal depression in experimental mice. Materials and Methods: Phyllathin was isolated from methanolic extract of PA and well-characterized using HPTLC, ESI-MS/MS, and LC/MS. Phyllathin containing a standardized extract of PA (50, 100, and 200 mg/kg) was administered in convulsed and kindled mice, followed by an assessment of various parameters. Results: The spectral analysis confirmed the molecular formula and weight of phyllanthin as C 24 H 34 O 6 and 418.2342 Da. PA (100 and 200 mg/kg) significantly ameliorated PTZ-induced ( p < 0.05) duration, onset of tonic-clonic convulsion, and mortality in mice. It also significantly attenuated ( p < 0.05) PTZ-induced kindling in mice. Alteration in brain GABA, dopamine, and glutamate, Na + K + ATPase, Ca +2 -ATPase activities, and oxido-nitrosative stress in kindled mice was significantly restored ( p < 0.05) by PA treatment. It also significantly ( p < 0.05) down-regulated brain mRNA expressions of NF-κB, TNF-α, IL-1β, COX-2, and TLR-4. Histological aberrations induced by PTZ in the brain of a kindled rat was significantly ( p < 0.05) ameliorated by PA. Conclusion: Phyllanthin containing a standardized extract of PA exerts its antiepileptic potential via balancing excitatory (glutamate) and inhibitory (GABA) brain monoamines, voltage-gated ion channels (Na + K + /Ca +2 -ATPase) and inhibition of NF-κB/TLR-4 pathway to ameliorate neuroinflammation (TNF-α, IL-1β, and COX-2) in experimental mice.

The modeling air-cooled turbine blades specimens of DD6 single crystal superalloy with different distributions of cooling film holes were used to study the high cycle fatigue properties at room temperature. The SEM fracture observation was carried out. The results indicate that the cooling holes have significant effects on the high fatigue life of DD6 single crystal superalloy. The average life of non-hole specimens is four times of that of the three-row holes specimens under the same testing conditions. However, the distribution of cooling film holes has relatively less influence on fatigue life. The fracture of the specimens with non-hole is linear source by SEM analysis, but the cracks are found around the cooling film holes and the fracture of the specimens with single row to three rows is a typical multi-source rupture, and cracks all initiate from near film holes. According to fracture and crystallography theoretical conjecture, the cracks propagate along the {001} slip plane for non-hole, single-row holes and the middle location of the multi-row holes specimens. However, the cracks around the holes grow along the {111} slip plane for upper and lower holes of the specimens with multi-row holes. In addition, the distribution of stress field along cooling holes of four different specimens was analysed by FEM method. The results show that the fracture location and morphology of specimens are consistent well with numerical simulation analysis.

In order to improve the corrosion resistance of the silicone coatings, the graphene-modified hyperbranched polysiloxane (HBPSi-PDM-SGO) coatings have been prepared by silane-modified graphene oxide (SGO) doping with hyperbranched polysiloxane. The effect of different mass fractions of SGO on the thermal stability and corrosion resistance of the HBPSi-PDM-SGO coatings has been discussed. The results show that HBPSi-PDM-SGO has excellent thermal stability and good anti-corrosion performance. In addition, the silane-modified graphene oxide also improves the mechanical properties and shortens the curing time. [ABSTRACT FROM AUTHOR]