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Phosphatase-catalyzed hydrolysis of organic phosphorus is an important pathway for providing bioavailable phosphorus to aquatic organisms. In this paper, a eutrophic water body was used to investigate how phosphorus and heavy metal ions affect alkaline phosphatase activity (APA) and its kinetic properties. The results show that phosphate (PO43-), hexametaphosphate ((PO3)(6)(6-)), pyrophosphate (P2O74-), and beta-glycerophosphate (C3H4O6P2-) inhibit APA and the inhibition effects increased with increasing concentration at the range of 0.01-1 mmol L-1. Addition of heavy metal ions, that is, Co2+, Pb2+, and Cr6+ at concentrations of 1 mmol L-1, increased the APA 3.1-fold, 2.3-fold, and 2.7-fold, respectively. The Cu2+, Zn2+, and Ni2+ exhibited an inhibitory effect on APA in water. For 1 mmol L-1 Cu2+, the APA deceased by 37.7% relative to the control. As the concentrations of Cu2+, PO43-, (PO3)(6)(6-), and P2O74- increased, the V-max of the alkaline phosphatase (AP) remained stable and K-m increased, indicating that these ions are competitive inhibitors of AP. In addition, V-max/K-m decreased with increasing concentrations of Cu2+, PO43-, (PO3)(6)(6-), P2O74-, and C3H4O6P2-, demonstrating the decreased catalytic efficiency of the AP. In summary, phosphorus and heavy metal significantly affect conversion of organic phosphorus into bioavailable inorganic phosphorous by changing the APA in eutrophic water bodies.

Intense droughts and extreme precipitation events are likely to occur more frequently with global climate change. These drying-rewetting (DW) cycles affect the soil carbon (C) cycle. Biochar addition are reported to affect SOC mineralization and soil organic carbon (SOC) storage. However, the effects of biochar application on SOC mineralization during DW cycles are poorly understood. Two wheat straw (WS25) biochar produced at 300 °C (WS300) and 600 °C (WS600) were used to explore the effects of biochar on SOC mineralization under artificial DW cycles as compared to constant moisture (CM). It was found that biochar had different effects on SOC mineralization depending on biochar type or drying/rewetting period of DW cycles. Just like CK and WS25, WS600 application decreased SOC mineralization under DW cycles compared to CM. To some extent, SOC mineralization during DW cycles was similar to CM for WS300. The results suggested that WS300 addition diminished the reducing effect of DW cycle on SOC mineralization. In addition, biochar exhibited different effects on SOC mineralization depending on the drying and rewetting period under DW cycles. Biochar (WS300) addition during the drying period had less effect on SOC mineralization but increased the flush effect of SOC mineralization during the rewetting period. In conclusions, biochar application significantly affect SOC mineralization following DW cycles.

Aiming at the multi-depot heterogeneous vehicle routing problem under the time-dependent road network and soft time window, considering vehicle fixed cost, time window penalty cost and vehicle transportation cost, an optimization model of time-dependent multi-depot heterogeneous vehicle routing problem is established with the objective of minimizing distribution cost. According to the characteristics of the problem, a hybrid genetic algorithm with variable neighborhood search considering the temporal–spatial distance is designed. Customers are clustered according to the temporal–spatial distance to generate initial solutions, which improves the quality of the algorithm. The depth search capability of the variable neighborhood search algorithm is applied to the local search strategy of the genetic algorithm to enhance the local search capability of the algorithm. An adaptive neighborhood search number strategy and a new acceptance mechanism of simulated annealing are proposed to balance the breadth and depth required for population evolution. The validity of the model and algorithm is verified by several sets of examples of different scales. The research results not only deepen and expand the relevant research on vehicle routing problem, but also provide theoretical basis for logistics enterprises to optimize distribution scheme.

Crack direction will affect the ultrasonic wave reflected from it. Firstly, the correlation between crack direction and the reflected energy of ultrasonic is analyzed. Then, a mathematical model of crack direction and its reflected energy is developed due to the theory and methods of function approximation. Finally, aiming at the problem that the crack area must be known when using the model to estimate the crack direction, By observing the probability distribution of reflected wave energy of cracks with different areas and directions at different measurement distances, Using its law and mathematical model, an algorithm for estimating crack area and crack direction is designed. According to the related experiments, the study confirmed that both the estimation errors of the crack area and direction by the method are 5.25% and 8.21%, respectively.

Bioremediation, mainly by indigenous bacteria, has been regarded as an effective way to deal with the petroleum pollution after an oil spill accident. The biodegradation of crude oil by microorganisms co-incubated from sediments collected from the Penglai 19-3 oil platform, Bohai Sea, China, was examined. The relative susceptibility of the isomers of alkylnaphthalenes, alkylphenanthrenes and alkyldibenzothiophene to biodegradation was also discussed. The results showed that the relative degradation values of total petroleum hydrocarbon (TPH) are 43.56% and 51.29% for sediments with untreated microcosms (S-BR1) and surfactant-treated microcosms (S-BR2), respectively. TPH biodegradation results showed an obvious decrease in saturates (biodegradation rate: 67.85-77.29%) and a slight decrease in aromatics (biodegradation rate: 47.13-57.21%), while no significant difference of resins and asphaltenes was detected. The biodegradation efficiency of alkylnaphthalenes, alkylphenanthrenes and alkyldibenzothiophene for S-BR1 and S-BR2 samples reaches 1.28-84.43% and 42.56-86.67%, respectively. The efficiency of crude oil degradation in sediment with surfactant-treated microcosms cultures added Tween 20, was higher than that in sediment with untreated microcosms. The biodegradation and selective depletion is not only controlled by thermodynamics but also related to the stereochemical structure of individual isomer compounds. Information on the biodegradation of oil spill residues by the bacterial community revealed in this study will be useful in developing strategies for bioremediation of crude oil dispersed in the marine ecosystem.

Principal component analysis (PCA), positive matrix factorization (PMF), and the mean effects range-median quotient (MERM-Q) models were employed to determine occurrence levels, sources, and potential toxicological significance of polycyclic aromatic hydrocarbons (PAHs) in surface sediments of the Yellow River Estuary, China. Due to the grain size of sediments, cumulative effects, and distribution of oil fields, the total concentration of the 16 U.S. Environmental Protection Agency (US EPA) priority PAHs (T-PAHs) measured in sediments along transects in the offshore area was 119.51 ± 39.58 ng g−1 dry weight (dw), which is notably higher than that measured in rivers (75.00 ± 12.56 ng g−1 dw) and estuaries (67.94 ± 10.20 ng g−1 dw). PAH levels decreased seaward along all the studied transects in coastal Bohai Bay. Multivariate statistical analyses supported that PAHs in sediments were principally derived from coal and biomass combustion, oil pollution, and vehicular emissions. Based on the MERM-Q (0.0050 ± 0.0017), PAHs were at low potential of ecotoxicological contamination level. These results provide helpful information for protecting water resources and serving sustainable development in Construction of Ecological Civilization in the Yellow River Delta.

Un-restored (R0) and restored (in 2006 (R2006) and in 2002, (R2002)) coastal wetlands were selected to study phosphorus (P) storage capacity and the risk of P loss in the Yellow River Delta (YRD). The results showed that the maximum P sorption capacity (Qmax) in the wetland sediments varied between 201.8–1168.6 mg kg−1; the average value was 576.2 mg kg−1. Qmax increased with increasing time since restoration (R2002 > R2006 > R0). The eutrophication risk index (ERI) ranged between 0.27–2.07% and decreased with increasing time since restoration, but the relationship was not statistically significant (P > 0.05). A correlation analysis demonstrated that Feox, Mg, and Alox are the main P sorption agents in wetland sediments, whereas TOC, pH, and clay particles have an important effect on P sorption and release. The analysis suggests that we should restore degraded coastal wetlands to help reduce the P load to offshore waters.

Nine units in new-born intertidal zone of the Yellow River estuary, China were examined for concentrations of heavy metals (Pb, Cr, Cu, Zn and Ni) in sediments and plants. Heavy metal levels in surface sediments were in the order of Zn > Pb approximate to Cr > Cu approximate to Ni and generally increased in a seaward direction except for Z6 (Tamarix chinensis-Suaeda salsa zone) and Z7 (S. salsa-T. chinensis zone) units. Significant differences in metal concentrations of the 9 units were observed in the profiles (p Cu > Pb > Ni > Cr and differed among plants or tissues. The roots at Z2 (Calamagrostis pseudophragmites zone), Z3 (Imperata cylindrical zone) and Z4 (Phramites australis zone) units accumulated greater metals than shoots [TFs (translocation factors) 1), implying that intertidal plants showed different pathways in metal accumulation and internal transportation. Except for Pb, the concentrations of Cr, Cu, Zn and Ni in sediments were lower than the criteria of Class I recommended by the Environmental Quality Standard for Soils of China, Although heavy metal levels in intertidal zone were generally the lowest (Cr, Cu, Zn and Ni) or relatively moderate (Pb) compared with other estuaries or bays in Asia and Europe, high eco-toxic risk of Pb and Ni exposure still could be observed at Z4, Z6 and Z9 (mudflat zone) units. S. salsa was more suitable for the potential biomonitor or phytoremediation of all five heavy metals if intertidal sediments was seriously contaminated with increasing of pollutants loading in the Yellow River estuary. (C) 2014 Elsevier B.V. All rights reserved.

Sea cucumbers are traditional marine food and Chinese medicine in Asia. The rapid expansion of sea cucumber market has resulted in various problems, such as commercial fraud and mislabeling. Conventionally, sea cucumber species could be distinguished by their morphological and anatomical characteristics; however, their identification becomes difficult when they are processed. The aim of this study was to develop a new convenient method of identifying and distinguishing sea cucumber species. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis of mitochondrial cytochrome oxidase I gene (COI) was used to identifing five sea cucumber species (Apostichopus japonicus, Cucumaria frondosa, Thelenota ananas, Parastichopus californicus and Actinopyga lecanora). A 692 bp fragment of COI was searched for BamHI, KpnI, PstI, XbaI and Eco31I restriction sites with DNAMAN 6.0, which were then used to PCR-RFLP analysis. These five sea cucumber species can be discriminated from mixed sea cucumbers. The developed PCR-RFLP assay will facilitate the identification of sea cucumbers, making their source tracing and quality controlling feasible.

Intangible Cultural Heritage is of comparatively high value in culture, economy, science and tourism, which is at its peak of development and utilization. Intangible cultural heritage needs preservation, so the development and utilization of the digital storage of intangible cultural heritage are a subject of theoretical and practical values. Among the various complicated types of intangible cultural heritage, the authors choose Pang Wang Festival of Yao nationality of Guangdong Province of China as an example and apply the CIDOC Conceptual Reference Model to the construction of the entities and properties of the knowledge ontology of the Pang Wang Festival, and the well-constructed knowledge ontology has been stored in the database. This study has provided the solution to the construction of the knowledge ontology of the intangible cultural heritage and benefits the digital storage, preservation and management of intangible cultural heritage, which offers a new way of thinking and is of great significance to the preservation and inheritance of intangible cultural heritage.

Biochar, a by-product of biomass pyrolysis, has been suggested as a mean to combat climate change, and at the same time to achieve agricultural and environmental benefits. As one possible source of the components with high aromatic structure in soil humus, biochar is of great importance in increasing soil carbon storage and improving soil nutrient retention and nutrient availability, and in maintaining the balance of soil ecosystem. This paper briefly reviewed and synthesized recent findings and discussions regarding the production and characteristics of biochar, its effects on global climate change and particularly in relation to the environmental effects of biochar in soils. Agronomic benefits of biochar application are critically highlighted because researches show that biochar had varied effects on crop productivity thorough the different bio-physical interactions between the biochar and the soils, which are deserved for further investigations. Potential pitfalls and knowledge gaps were briefly discussed on the environmental behavior and the effects of biochar in agricultural ecosystem.

BACKGROUND: Sea urchin gonads are highly valued seafood that degenerates rapidly during the storage period. To study the influence of dissolved oxygen concentration on quality changes of sea urchin (Strongylocentrotus nudus) gonads, they were stored in artificial seawater saturated with oxygen, nitrogen or air at 5 ± 1 °C for 12 days. RESULTS: The sensory acceptability limit was 11–12, 6–7 and 7–8 days for gonads with oxygen, nitrogen or air packaging, respectively. Total volatile basic nitrogen (TVB-N) values reached 22.60 ± 1.32, 32.37 ± 1.37 and 24.91 ± 1.54 mg 100 g−1 for gonads with oxygen, nitrogen or air packaging at the points of near to, exceeding and reaching the limit of sensory acceptability, indicating that TVB-N values of about 25 mg 100 g−1 should be regarded as the limit of acceptability for sea urchin gonads. Relative ATP content values were 56.55%, 17.36% and 18.75% for gonads with oxygen, nitrogen or air packaging, respectively, on day 2. K-values were 19.37%, 25.05% and 29.02% for gonads with oxygen, nitrogen or air packaging, respectively, on day 2. Both pH and aerobic plate count values showed no significant difference (P > 0.05) for gonads with the three treatments. CONCLUSION: Gonads with oxygen packaging had lower sensory demerit point (P < 0.05) and TVB-N values (P < 0.05), and higher relative ATP content (P < 0.01) and K-values (P < 0.05), than that with nitrogen or air packaging, with an extended shelf life of 4-5 days during storage in artificial seawater at 5 ± 1 °C. Copyright © 2011 Society of Chemical Industry

RFID (Radio Frequency Identification) is a new technology making use of radio frequency to do non-touch- ing, two-way data transit between the reader and the electronic tag to identify target and exchange data. Because it is non-touching; it can work from long distance; it is fit to work in an unfavorable environment; it can identify moving target, it is widely used in industry, commerce, storage, transportation. This paper introduces the application of the RFID technology and its state of development and discusses the general situation of its application in different fields. Moreover, this paper takes the tourist mini-train as an example, designs a security monitoring system based on RFID and discusses its application in tourist industry.

Seven carboxylic acids in rainwater were simultaneously determined using ion chromatography for 13 months in two different sites, Guiyang and Shangzhong, southwest of China. Results showed formic, acetic and oxalic acids were the three predominant carboxylic acids. Their volume-weighted average concentrations were 14.24, 9.35, 2.79 μmol/L in Guiyang and 4.95, 1.35, 2.31 μmol/L in Shangzhong, respectively. A distinctive diurnal pattern in carboxylic acid concentrations (daytime>nighttime, t test, p < 0.05) was observed during the growing season in Guiyang. Shangzhong witnessed higher concentration of these acids during the growing season than that during the non-growing season. Direct emissions from growing vegetation or soils probably account for the main provenance of the acids in the rural area. However, the opposite trend were found in Guiyang and the anthropogenic sources during the non-growing season were the main reason. By comparison of our result with the previous data about 20 years ago, we calculated that at least 42% of acetic acids and 69% of formic acid originated from the anthropogenic sources in Guiyang. Furthermore, the ratio of formate/acetate in gas phase larger than 1 suggest the oxidation of unsaturated hydrocarbons from the human activity and/or natural sources were the main origin of carboxylic acids in Guiyang. While The F/A ratio in gas phase was less than 1 in Shangzhong which indicate the direct emissions from biogenic sources. Oxalic acid was in similar amounts in both sites, indicating the common source of the acid.

As the tourism industry has gradually become the strategic mainstay industry of the national economy, the scope of the tourism discipline has developed rigorously. This paper makes a predictive study on the development of the scope of Guangdong provincial tourism discipline based on the artificial neural network BP model in order to find out how the branch of tourism studies can better adapt to the development of the tourism industry. The research findings indicate that the BP model can be applied to the predictions of the scope of the tourism discipline and provide a quantitative basis for decision making with regard to the spatial layout and optimal allocation of the tourism discipline.

Sea urchin gonads are highly valued seafood that degenerates rapidly during the storage period. To study the influence of dissolved oxygen concentration on quality changes of sea urchin (Strongylocentrotus nudus) gonads, they were stored in artificial seawater saturated with oxygen, nitrogen or air at 5 ± 1 °C for 12 days.The sensory acceptability limit was 11-12, 6-7 and 7-8 days for gonads with oxygen, nitrogen or air packaging, respectively. Total volatile basic nitrogen (TVB-N) values reached 22.60 ± 1.32, 32.37 ± 1.37 and 24.91 ± 1.54 mg 100 g(-1) for gonads with oxygen, nitrogen or air packaging at the points of near to, exceeding and reaching the limit of sensory acceptability, indicating that TVB-N values of about 25 mg 100 g(-1) should be regarded as the limit of acceptability for sea urchin gonads. Relative ATP content values were 56.55%, 17.36% and 18.75% for gonads with oxygen, nitrogen or air packaging, respectively, on day 2. K-values were 19.37%, 25.05% and 29.02% for gonads with oxygen, nitrogen or air packaging, respectively, on day 2. Both pH and aerobic plate count values showed no significant difference (P0.05) for gonads with the three treatments.Gonads with oxygen packaging had lower sensory demerit point (P0.05) and TVB-N values (P0.05), and higher relative ATP content (P0.01) and K-values (P0.05), than that with nitrogen or air packaging, with an extended shelf life of 4-5 days during storage in artificial seawater at 5 ± 1 °C.

Modified S-BLM (Solid Supported Bilayer Lipid Membrane) is a kind of sensitive element similarly to biologic membranes. It was found that modified S-BLM conductance was closely related to its sensitivity. The theory of research methods was firstly demonstrated and established. I2 modified S-BLM and C60 modified S-BLM, which were all supported by stainless steel needle, was studied objects. Through establishing and analyzing the functional relationship between response and excitation, the conductance characteristics of modified S-BLM were studied by the contrastive test method. From data, the transferring characteristics of modified S-BLM conductance to the measured signal were illuminated; the relationship between S-BLM conductance and excitation-response characteristics, modifier performance, measured physical quantity were showed; the important roles of modified S-BLM were explained in the process of identifying and transferring signal. According to the experimental data, the transferring mechanism of modified S-BLM conductance to measured signal was profoundly analyzed, and the internal relationship between stimulus and response was showed.

Little is known about the effects of air-drying and freezing on the transformation of phosphorus (P) fractions in soils. It is important that the way in which soils respond to such perturbations is better understood as there are implications for both P availability and loss to surface waters from soils. In this study, the effects of air-drying and freezing were investigated using two soils, one being a forest soil (FS) high in organic matter and the other being a sterile soil (SS) low in organic matter. Soil P was fractionated using a modified Hedley fractionation method to examine the changes of phosphorus fractions induced by air-drying and freezing. Generally, there were no significant differences of total phosphorus among the three treatments (CV% < 10%). Compared with field moist soils, freezing the soil evoked few changes on phosphorus fractions except that the resin-P increased in FS soil. On the contrary, air-drying significantly changed the distribution of phosphors fractions for both soils: increased the labile-P (especially resin-P) and organic-P (NaHCO(3)-Po, NaOH-Po and Con. HCl-Po) at the expense of NaOH-Pi and occlude-P (Dil. HCl-P and Con. HCl-Pi). Resin-P significantly increased by 31% for SS soil and by 121% for FS soil upon air-drying. The effect of air-drying seemed to be more pronounced in the FS soil with high organic matter content. These results indicated that drying seem to drive the P transformation form occlude-P to labile-P and organic-P and accelerated the weathering of stable P pool. This potentially could be significant for soil P supply to plants and P losses from soils to surface waters under changing patterns of rainfall and temperature as predicted by some climate change scenarios.