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In this paper, we comprehensively compare the application effects of five least-squares adaptive matched filtering methods (the single-channel, the multichannel, the equipoise multichannel, the pseudo multichannel and the equipoise pseudo multichannel) for multiple suppression in three representative datasets with different degrees of orthogonality. By introducing an error function, we can quantitatively analyse the influence of the five methods for multiple suppression in terms of the filter length, the normalized regularization factor, the number of matched channels, the iteration number, the amplitude ratio and noise immunity. In addition, we provide the corresponding optimal parameters or their selection principles. The comparison results show that: (i) the dependence on orthogonality is not the same for these five methods; only the equipoise multichannel and the equipoise pseudo multichannel methods can effectively reduce the dependence on orthogonality; (ii) the single-channel method is relatively balanced in all aspects; (iii) the pseudo multichannel and the equipoise pseudo multichannel methods have a stronger shaping ability but generate larger errors; (iv) the multichannel method requires a higher degree of orthogonality and (v) the optimal parameters derived from the three datasets will be better reference values for complex models or field data for the multiple suppression.

Seismic surface-related multiples have become a hot topic of great significance due to the buried geological information provided by broader illumination areas than primaries. In recent years, researchers attempt to extract the hidden hint of multiples rather than treating them as noise and eliminating them directly. The elimination methods, e.g., the surface-related multiple elimination (SRME) and the inverse scattering series free-surface multiple elimination (ISS-FSME), may be affected by the overlapping or proximity of primaries and multiples. Typical imaging methods, e.g., the reverse time migration (RTM) and the least-square reverse time migration (LSRTM), suffer severe crosstalk artifacts from multiples of inappropriate order and smooth migration velocities. To study the characteristics of primaries and surface-related multiples, whether for elimination or imaging, we propose a forward modeling method of acoustic surface-related order-separated multiples established on the areal/virtual source assumption. The free surface is replaced with an absorbing surface under the dipole source approximation and the ghost creation approach. We present two reflection operators to approximate the reflection at the free surface and apply them to the areal source to obtain ideal results. Numerical experiments on three models prove the effectiveness of the proposed forward modeling method of acoustic surface-related order-separated multiples.

In order to know the key factors of callus development on single cell clone, characteristics of physiology and biochemistry and morphological structure on two types of Alfalfa callus was studied. The results showed that the cell membrane permeability and malondialdehyde content was same on two types of callus; but, their soluble sugar content and peroxidase activity in cells was larger different, the soluble sugar content: soft callus > huge callus, and soft callus was 2.09 times of huge callus; peroxidase activity: huge callus > soft callus, and huge callus was 1.35 times of soft callus. Huge callus cells were larger, loosely arranged, cell vacuolization and cytoplasm was thinner than soft callus. However, soft callus cells were smaller, loosely arranged, cell vacuoles was smaller and cytoplasm was thicker than hug callus. Huge cells had the same membrane metabolic with soft cells, but soft cells had higher sugar accumulation than huge cells, and soft cells metabolism are vigorous, while huge cells are more aging.

In order to explore the relation between tree crown shape and growth development and age of tree, flowering plants, fruiting plants, bearing plants, bearing branch and floweret, length of bearing branch were studied in greenhouse environments after tree corm shape were divided into three groups by live crown ratio of crown width to height and angle from the central leader to first scaffold branch. The result showed that the plants of upright crown shape were 83% at age one year among all plants, 45% at age two years and tree crown shapes, open tree increased to 25% at age of three years. The flowering trees increased from 5% at age of one year to 55% in age of three years and fruit set increased from 0 to 44% following increase of age tree. Open trees had more flowers with 10.6 in 2-year-old tree, 38.6 in 3-year-old tree. Open trees had more percentage of bearing plants with around 47%. The average length of bearing branches was 11.5 cm at open trees, which was more than other crown shapes at age of three years. Open trees had most fruit number per bearing tree (6.5, 8.5 apart). Therefore, creating open tree crown shape may increase flowering, fruiting and yield in greenhouse production of feijoa.

In order to understand the effects of lead on the growth of Lactuca sativa L. and Brassica Campestris L. ssp, the change of growth index of seedling was studied under lead stress (different concentrations of lead nitrate solution), and by soilless cultivation of seedlings in pots and in greenhouse. The results showed that two kinds of plant growth were affected by lead stress of different level, the growth speed of seedlings reduced but a great number of growth index were increased, in addition to fresh weight and dry weight of stem and leaf. The leaf number, leaf area, plant height and the fresh weight, dry weight of stem and leaf in Lactuca sativa L. were declined obviously, and the fresh weight, dry weight of roots were increased under higher levels of lead treatment at the same time. The each growth index of Brassica Campestris L.ssp was decreased in higher concentration of lead treatment. The growth of Lactuca sativa L. was slightly better and Brassica Campestris L. was slightly lower than control under 0.005 mg/L lead treatment. So, Lactuca sativa L. wasmore sensitive in low concentrations of lead than Brassica Campestris L. Both of them reduced their growth significantly, especially Brassica Campestris L.in 0.015 mg/L lead treatment. Each grow index of Lactuca sativa L.and Brassica Campestris L. changed most in all kinds of lead concentration, and the growth was inhibited most in 0.045 mg/L lead. The growth of Brassica Campestris L.was decreased more under higher concentrations of lead compared with Lactuca sativa L..

In the northern China, Tuberose is planted in spring following man-forced dormancy in winter and blooms in summer or autumn. The forcing culture was carried out under greenhouse environment to advance blooming to spring and to evaluate the vegetative and reproductive characteristics of tuberose. Effects of three planting dates (30th Oct., 30th Nov, and 20th Dec), two cultivars (Single and Double) were determined. The results showed that Oct planting gave more percentage of corm sprouting, longer spikes and flower stems, more but smaller florets; however, more number of days was required to bloom than other planting dates. Double variety normally had more sprouting, flowering, florets, shorter spikes, and better quality of cutting flower, but it bloomed later than Single variety. The quality of cutting flowers produced in the greenhouse was decreased compared with local field produced flowers, particularly when planting date was late, with the exception of Double in Oct planting. So, the forcing cultivation of tuberose may be performed with Double and in Oct planting in local greenhouse and without man-forced winter dormancy of corm after harvest.

To understand the effects of different rootstocks on the growth of sweet cherry in greenhouse environment, The change of physiological and biochemical indexes of SUM variety grafted on dwarf stock (gisela 5) and the vigorous stock (mahaleb) was studied with biennial seedlings cultivated in greenhouse of north China. The results showed that dwarf stocks could increase content of Malonaldehyde (MDA), proline (PRO), activity of Superoxide dismutase (SOD) and decreased the membrane relative permeability in the leaves of SUM compared with vigorous rootstocks. So the dwarf stocks could increase the resistance of plants. The vigorous stock could decrease content of MDA, but the activity of Peroxidase (POD) was same in the leaves of SUM grafted on both of rootstocks. So, the dwarf rootstock should be better than vigorous stock on increasing resistance or drought and salt tolerance of the cherry varieties SUM.