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The accumulation of nitrate in vegetables is paid close attention to for one's health in the world. This paper highlights researching effects of extraneous glutamic acid (Glu), which is the middle product in the path of nitrogen metabolism, on nitrate accumulation in Chinese chive (Allium tuberosum Rottler Spreng) by means of spraying leaves with the glutamic acid solution. Glutamic acid solution at the concentration level of 0.5-10 mmol·L -1 decreased nitrate contents in Chinese chive leaves. Especially, the treatment of Glu at 5 mmol·L -1 produced an obvious increase of 15.1%. However, the total-N (nitrogen) content increased in Chinese chive leaves as increasing of Glu concentration at the range of 0.5-10 mmol·L -1 . Meanwhile, activity of nitrate reductase (NR) and glutamine synthetase (GS) raised by a wide margin, and chlorophyll content increased from 13.7 to 29.5%. In addition, the contents of free amino acid, soluble protein, and soluble sugar also increased. The results showed that extraneous glutamic acid did not only improve activity of NR named as "N-reducing-driving-pump" and activity of GS called "first driving pump" in the path of N assimilation, but also provides enough reducing force e - , ATP and C-framework, e.g., α-ketoglutarate for glutamate synthase (GOGAT) which is called "the second driving pump" in the path of N assimilation. Therefore, spraying the glutamic acid on leaves accelerated assimilation of nitrate in Chinese chive leaves. As a result, application of glutamic acid did not only reduce nitrate accumulation, but also improved the quality of Chinese chive.

To probe pollution ecology effects of pesticide in vegetables, the chlorophyll fluorescence transients were measured by a Plant Efficiency Analyzer (PEA; Hansatech Ltd., King's Lynn, Norfolk, England) in no-heading Chinese cabbage, and the activity of photosystem II (PS II) was analyzed by the fluorescence transient (the JIP-test). Three pestcides, including phorate, phoxin and cypermetrin, were sprayed on the leaves of no-heading Chinese cabbage. The results showed that on the third day after treatments, these pesticides could promote reducing from primary quinone acceptor Q A to Q A - in PS II, e.g., increasing parameters in relation to J phase, i.e., relative variable fluorescence at the J-step (V J ) and approximated initial slope of the fluorescence transient (M o ). Meanwhile they prohibited electron transmission from Q A - to Q B in PS II, e.g., sharply decreasing parameters of electron transport flux per PS II reaction center (ETo/RC), probability that a trapped exciton moved an electron into the electron transport chain beyond Q A - (ψ o ) and quantum yield of electron transport (ϕ Eo ), and further resulted in sharping decrease of driving force on absorption and cross section basis of PS II (DF ABS and DF CS ), respectively. Effects of phorate on the above parameters showed that dynamic change of residuals was significant and strongly related to the dosage, which would be loss of effect gradually from the fifth day after treatment.

Real contact projection area is a key parameter of the evaluation models of the materials' mechanical properties using nanoindentation. If the geometrical parameters of the indenter are known, the real contact projection area may be determined based on the relation between the real contact depth determined according to the unloading curve and the geometrical parameters of the indenter and the real contact projection area. If the real geometrical parameters of the indenter are not known, the real contact projection area is obtained using testing method. In this paper, two kinds of testing methods, the standard block method (including the standard elastic modulus block method and the standard hardness block method) and the non-standard block method, are introduced for the determination of the real contact projection area.

We study the inclined oil‐water two‐phase flow using complex networks and construct flow pattern complex network with the conductance fluctuating signals measured from oil‐water two‐phase flow experiments. A new method, based on Time‐Delay Embedding and modularity, is proposed to construct network from nonlinear time series. Through detecting the community structure of the resulting network using the community‐detection algorithm based on K‐means clustering, useful and interesting results are found which can be used to identify three inclined oil‐water flow patterns. In this paper, from a new perspective, we not only introduce complex network theory to the study of oil‐water two‐phase flow, but also demonstrate that complex network may be a powerful tool for exploring nonlinear time series in practice.

The creep properties of geogrid influence greatly the long-term service behavior of geogrid reinforced retaining structures. The comparing tests on the creep properties of plastic geogrid were carried out in the lab, with various load and temperature combinations. Based on the comprehensive comparison of the test results, the creep properties of plastic geogrid under low temperature and the changing characteristics of the load strain isochronous curve were studied of, and the influence of the freeze-thaw cycling on the plastic geogrid creep properties was described.