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A study on contamination status and ecological risk of heavy metals in surface sediment at selected sites on Kelantan River and its nearshore area was carried out. Ten samples along Kelantan River and 25 samples from the nearshore were analyzed using inductively coupled plasma optical emission spectrometry (ICP-OES) to determine heavy metal concentrations. Sediment samples were also analyzed for particle size compositions, total organic matter and pH content. The average concentrations for As, Cd, Cr, Cu, Mn, Ni, Pb, Zn were 7.38, 1.31, 17.71, 11.40, 507.15, 5.97, 22.61, 32.95 mg/kg for riverine and 14.14, 4.59, 29.79, 14.07, 389.96, 9.65, 62.21, 41.04 mg/kg for nearshore samples respectively. The potential ecological risk index showed stations Bekok, Manek Urai, and RH under considerable risk followed by station Pasir Mas under moderate risk. The pollution load index classified four nearshore sites (KW10, KW17, KW18, KW37) as polluted. The geo-accumulation index (Igeo) categorized moderate contamination for Cd and Pb. The enrichment factor (EF) along the river categorized extremely high enrichment for Cd, and significant enrichment for As, Pb and Mn while Pb and As were under very high and significant enrichment in nearshore areas. Pb, Cu, Zn, As, Ni and Cr showed significant correlations with each other.

Tropical mountain river systems that drain rainforests and experience tropical monsoons typically demonstrate high runoff and discharge a disproportionate amount of particulate load to the world’'s oceans compared with other more temperate river systems. As a typical tropical small mountainous river with an broad continental shelf system and wave dominated environment, the Kelantan River is one of the few north-flowing streams in Southeast Asia that discharges into the broad and shallow continental shelf of South China Sea. The existence of seasonal variations of salinity, turbidity, and sediment composition indicate that coarse-grained sediments are deposited rapidly when terrestrial sediments delivered by the Kelantan River leave the river mouth. They are then reworked by wave action during the rainy season, leading to the development and rapid migration of barrier spits near the west side of the river mouth. Under the influence of the seasonal variations in the river plume, fine-grained sediments discharged into the sea by the Kelantan River are transported both along-shore and cross-shore, and most of them are deposited in the continental shelf area within 10 km of the river mouth, because of rapid removal of sediments from the river plume. The spatial distribution patterns of sediment composition, C/N ratio, terrestrial organic carbon content, and Sr/Al ratio also support our conclusion.

Sedimentary processes in the subaqueous deltas of small mountainous rivers are very sensitive to environmental variation within the river basin and hydrodynamic conditions near the estuarine environment. Through radiometric dating and sediment grain size analysis of core sediments collected in the subaqueous delta area of the Minjiang River (MJR), we studied the sedimentary processes in this area since the 1950s and revealed their responses to human activities within the MJR basin. The dry density of core sediments in the MJR subaqueous delta varied from 0.81 to 1.32 g/cm3. The mean sedimentation rate was 0.61 cm/yr (0.68 g/cm2⋅yr) before 1963, and has increased to 1.04 cm/yr (1.05 g/cm2⋅yr) between 1963 and 1986, and then decreased to 0.46 cm/yr (0.41 g/cm2⋅yr) between 1986 and 2014. The core sediments were composed primarily of silt, and the main sediment type was clayey silt; the mean grain size varied from 5.1 to 22.3 μm, with a mean value of 10.3 μm. With increasing anthropogenic activity within the MJR catchment, the land use pattern changed markedly. Soil erosion intensified, and the sediment flux discharged by the MJR to the sea clearly increased; consequently, the sedimentation rate in the subaqueous delta also increased. However, owing to dam construction, large quantities of sediment were trapped within reservoirs, decreasing the sediment flux discharged by the MJR to the sea, affecting the sedimentation rate in the subaqueous delta and also changing the sediment frequency curve from a bimodal pattern to a single-peak pattern.

The surface of TiO2 inverse opal material was modified by Liquid Phase Deposition(LPD) method, and a layer of TiO2 nanoparticles was deposited on the inverse opal framework in order to increase the specific surface area. The photo-catalytical degradation of Rhodamine B was used as the probe-reaction to investigate the photocatalysis ac- tivity of the TiO2 inverse opal membranes, and the influences of boric acid concentration of the LPD solution on surface morphology and photocatalysis activity of TiO2 inverse opal membranes were investigated. The results showed that the photocatalysis activity of TiO2 inverse opal membrane modified by LPD method was improved which was about 6 times higher than that of the unmodified TiO2 inverse opal when the boric acid concentration of PLD solution was 0.0183 g/mL.

Visual attention is a kind of selection which points at relevant information and restrains irrelevant information.Working memory(WM) plays a role in holding associated information and suppressing unassociated information.This paper is based on systematic reviews of existing literature on guidance of visual attention from WM and combines recent research on event related potential(ERP).From the visual search based on the two points of view of attentional capture and attentional suppression of the content of WM,we summarized the related research of visual working memory(VWM) and visual selective attention.Researchers have mainly been discussing two aspects in this field:(1) the guidance of visual attention from WM;(2) the conditions of the guidance of visual attention from WM.It suggests that no matter the contents of VWM capture or restrain attention,there are top-down and bottom-up two kinds of processing mechanism.

Four short cores were obtained from the coastal wetland of the Quanzhou Bay, Fujian Province, China, and sediment samples were analyzed with a Mastersizer 2000 for grain size analysis and an Inductively Coupled Plasma Atomic Emission Spectrometer (ICP-AES) for trace metal analysis. The results of grain size analysis show that the wetland sediments are mainly composed of silt and clay, and the distribution of median grain size is affected by human activities obviously. The results of trace metal analysis show that the wetland sediments mainly originate from terrestrial materials in the Luoyangjiang River estuary and from contaminants discharged from adjacent rivers in Shuitou area. The heavy metal contamination in Luoyangjiang estuary decreased from 1984 to 2004 due to industry transformation, but has increased since 2004 because of the discharge of contaminants to the Jinjiang River and much living sewerage to the bay, and a large number of trace metals are trapped within Spartina alterniflora marsh.

In addition to the phonon variable there is the phason variable in hydrodynamics for quasicrystals. These two kinds of hydrodynamic variables have different transformation properties. The phonon variable transforms under the vector representation, whereas the phason variable transforms under another related representation. Thus, a basis (or a set of basis functions) in the representation space should include such two kinds of variables. This makes it more difficult to determine the physical property tensors of quasicrystals. In this paper the group-theoretical method is given to determine the physical property tensors of quasicrystals. As an illustration of this method we calculate the third-order elasticity tensors of quasicrystals with five-fold symmetry by means of basis functions. It follows that the linear phonon elasticity is isotropic, but the nonlinear phonon elasticity is anisotropic for pentagonal quasicrystals. Meanwhile, the basis functions are constructed for all noncrystallographic point groups of quasicrystals.

Coastal salt-marshes represent an important coastal wetland system. The total area of coastal wetlands exceeds 5000 km2 in Jiangsu Province, China, but it is decreasing rapidly in response to the intense reclamation activities and coastal erosion along a part of the coastline. Hence, two types of plants,Spartina angelica andSpartina alterniflora, were introduced successively into the Jiangsu coastal areas, in order to protect the coastline from erosion and to increase the accumulation rate. Pb-210 and Cs-137 analyses were carried out for sediment samples from the salt-marshes of Wanggang to determine the sedimentation rate, on the basis of an evaluation of the background activity values and the factors affecting the enrichment of Pb-210. Analysis of a typical sediment column of the tidal flat shows that there is weak absorption of Pb-210 in the silt-dominated sediment. Because of the influences of factors such as storm events, bioturbation, material sources and analytical error, some abnormal data points appear in the Pb-210 record. After ignoring these data the calculated sedimentation rate was 3.3 cm yr−1 on average. Based upon analysis of the Cs-137 dating, the rate since 1963 was 3.1 cm yr−1 on average, similar to the data by Pb-210 dating and the previous studies. The dating results show that there were three stages of sedimentation, with the most rapid accretion being taking place afterSpartina angelica was introduced into the area. The study also shows that at the stage ofSpartina alterniflora growth, the accretion rate was higher than on the flat surface with the same elevation without the cover of this plant.

The relations between Hall effect and symmetry are discussed for all 2- and 3-dimensional quasicrystals with crystallographically forbidden symmetries. The results show that the numbers of independent components of the Hall coefficient (R u) are one for 3-dimensional quasicrystals, two for those 2-dimensional quasicrystals whose symmetry group is non-Abelian, and three for those 2-dimensional quasicrystals whose symmetry group is Abelian, respectively. The quasicrystals with the same number of independent components have the same form of the components ofR n.

In August 2010, serious deformation occurred in the Wangxia dangerous rock mass. It formed a large dangerous factor for the local resident and channel safety. Based on the detailed investigation of the crack, deformation history, GPS observations and crack displacement monitoring data analysis, analysed comprehensively the deformation of Crack T10 and relationship with the dangerous rock. The results show that Crack T10 is controlling crack and the back edge of the deformation zone. Each segment of the crack was mainly on settlement during aggravation deformation period. East and west segmentation of the crack was mainly on settlement during gentle transition period, but the tension deformation of the middle segmentation was stronger than settlement deformation. The dislocation of each segment was not obvious. This was mainly caused by the crack extension direction different from the overall deformation direction of the rear edge of the dangerous rock, and controlled by the deformation direction of the rear edge collapse pits. Crack T10 was closely associated relation with the dangerous rock mass and the deformation had bigger effect with the old cracks and mining activities at the bottom. Crack T10 also was the key area to react the dynamic deformation and failure of the dangerous rock. And also can provide efficient accurate real-time information for the warning forecast work of Wangxia dangerous rock. According to the geological conditions and the deformation character of Crack T10, think Wangxia dangerous rock is subsided extrusion type collapse.

This study probes into present humanistic situation of science students in China, and on the ground of constructive teaching methodology, put forward a basic hypothesis, i.e., quality-oriented education is more effective than test-oriented education. The result of the research proved that the integration of language skill training and humanity quality cultivating with English teaching as the platform contributed to the improvement of their humanistic knowledge and the elevation of their cognitive competency and aesthetic response. Besides, the amplification of comprehensible input boosted the improvement of their output competence and strengthened their pragmatic awareness, hence, effectively achieve the purpose of reforming college English education.

Self-assembling of colloidal particles dispersed in a mixture of ethanol and water at the air-liquid interface of the colloidal suspension at room temperature is investigated, and a method of rapidly assembling colloidal particles is proposed. By this method, a uniform colloidal crystal thin film over ten square centimeters in area can be fabricated in 10 min without special facilities and heating the suspension. SEM images and a normal incidence transmission spectrum of the sample show that the colloidal crystal film fabricated by this method is of high quality. In addition, this method is very suitable for fabricating colloidal crystal heterostructures.

Colloidal photonic crystal heterostructures, composed of two opaline photonic crystal films of silica spheres with different diameters, are fabricated by a two-step spin-coating method. Scanning electron microscopy (SEM) and UV-vis spectrophotometer are used to characterize the heterostructures. The SEM images show good ordering of the two-layer colloidal crystals constituting the heterostructures. The transmission spectra measured from the (111) plane in the heterostructure show that the composite colloidal photonic crystals have double photonic stop bands. Furthermore, when the sizes of the silica spheres used for fabricating the composite photonic crystal are slightly different, the transmission spectrum shows that the composite photonic crystals have more extended bandgap than that of the individual photonic crystals due to partial overlapping of its two photonic stop bands.