Rain Water Utilizing System Combing Artificial Wetland and Urban Drainage System

The method of utilizing rain water has been well developed in foreign countries to realize the sustainable development of water recourse while the method is still at the initial level in China. When considering the increasing of water shortage and urban flood, the awareness of utilizing rain water, as an inevitable trend, has been applied to various engineering technologies. This article has analyzed the principle of conventional road drainage system and the application of artificial wetland technology, also proposed to combine the road drainage system and artificial wetland, as a complex drainage system, to utilize the urban rain water, decrease urban flood pressure, and improve urban micro environment. The calculation principle and method for the complex drainage system are included as well.

Succession and seasonal variation in epilithic biofilms on artificial reefs in culture waters of the sea cucumber Apostichopus japonicus

Periphytic biofilms in aquaculture waters are thought to improve water quality, provide an additional food source, and improve the survival and growth of some reared animals. In the AsiaPacific region, particularly in China, artificial reefs are commonly used in the commercial farming of sea cucumbers. However, few studies have examined the epilithic biofilms on the artificial reefs. To gain a better understanding of the succession of epilithic biofilms and their ecological processes in sea cucumber culture waters, two experiments were conducted in culture waters of the sea cucumber Apostichopus japonicus in Rongcheng, China, using artificial test panels. On the test panels of succession experiment, more than 67 species were identified in the biofilms. On the test panels of seasonal variation experiment, more than 46 species were recorded in the biofilms. In both experiments, communities of epilithic biofilms were dominated by diatoms, green algae and the annelid Spirorbis sp. In the initial colonization, the dominant diatoms were Cocconeis sp., Amphora spp. and Nitzschia closterium in June, which were succeeded by species of Navicula, Cocconeis and Nitzschia(July to September), and then by Licmophora abbreviata, Nitzschia closterium and Synedra spp. in the following months. A diatom bloom in the autumn and filamentous green algae burst in the summer were also observed. Ecological indices well annotated the succession and seasonal changes in epilithic communities. Multidimensional scaling(MDS) analysis found significant differences in diatom community composition among months and seasons. Fast growth of biofilms was observed in the summer and autumn, whereas the biomass of summer biofilms was largely made up of filamentous green algae. Present results show that the components of epilithic biofilms are mostly optimal foods of A. japonicus, suggesting that biofilms on artificial reefs may contribute important nutritional sources for sea cucumbers during their growth seasons. Future works should include quantitative determination of the contribution of epilithic biofilms to the diet of A. japonicus, potential roles of epilithic biofilms in regulating the water quality of sea cucumber ponds, and the regulation of epilithic biofilms in sea cucumber culture ponds.

Numerical method for wave height distribution within the artificial harbor with water depth of steep variation

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Protozoan colonization on artificial substrates in relation to water quality in a tropical Indian harbour

A field study was conducted to evaluate the protozoan colonization patterns on artificial substrates in relation to organic pollution within a tropical harbour. The composition of protozoans and their succession rates on artificial substrates(polyurethane foam units) were compared between two field stations(A and B), and their presence were considered with regards to the prevailing water quality conditions at the study sites. Altogether 44 genera of flagellates and ciliates were documented. The common genera of flagellates encountered included Monas, Polytoma, and Chromalina. Among the ciliates, the predominant genera were Tetrahymena, Vorticella, Lagynophyra, and Heloiphyra. These groups exhibited characteristic successional patterns in relation to ambient water quality. At Station A, located close to the sewage outfall, the water quality parameters included poor Secchi disc transparency(0.48m), dissolved oxygen of 1.93 mg/ml, salinity of 18 psu, and temperature 31.3 ℃. Here, the nanoflagellates( spumella ) colonized first, followed by microcilliate( Tetrahymena ) and sessile form( Vorticella ). Station B, located on the seaward side, was characterized by relatively less stressed environmental conditions with transparency 1.85m and dissolved oxygen value of 6 04 mg/ml. Salinity of 27.27 psu, and mean temperature of 30 ℃ were recorded at “B'. At this station, the nanoflagellate Polytoma was first documented to colonize on the substrates, followed by microcilliate( Lagynophrya ) and suctorid( Heliophyra ). These findings support the use of protozoans as indicator species for evaluating the hazards posed by organic pollution to natural estuarine communities.

Artificial Water Channel Promoting Depolymerization of Actin Filaments to Trigger Cancer Cell Apoptosis

Actin filaments play important physiological functions,which have become potential targets of antitumor drugs.Using chemicals to intervene their polymerization-depolymerization dynamics would generate new strategies for designing antitumor drugs.In this report,an artificial water channel appending acetazolamide moiety,a ligand that can selectively bind to carbonic anhydrase IX,has been prepared.

Experimental study of water curtain performance for gas storage in an underground cavern

An artificial water curtain system is composed of a network of underground galleries and horizontal boreholes drilled from these galleries.Pre-grouting measures are introduced to keep the bedrock saturated all the time.This system is deployed over an artificial or natural underground cavern used for the storage of gas（or some other fluids） to prevent the gas from escaping through leakage paths in the rock mass.An experimental physical modeling system has been constructed to evaluate the performance of artificial water curtain systems under various conditions.These conditions include different spacings of caverns and cavern radii located below the natural groundwater level.The principles of the experiment,devices,design of the physical model,calculation of gas leakage,and evaluation of the critical gas pressure are presented in this paper.Experimental result shows that gas leakage is strongly affected by the spacing of water curtain boreholes,the critical gas pressure,and the number and proximity of storage caverns.The hydraulic connection between boreholes is observed to vary with depth or location,which suggests that the distribution of water-conducting joint sets along the boreholes is also variable.When designing the drainage system for a cavern,drainage holes should be orientated to maximize the frequency at which they encounter major joint sets and permeable intervals studying in order to maintain the seal on the cavern through water pressure.Our experimental results provide a significant contribution to the theoretical controls on water curtains,and they can be used to guide the design and construction of practical storage caverns.

Visualization of the Motion of Textiles through a Waste Water Pump at Different Operating Points

In this paper,?the motion of textiles through a waste water pump is studied by aid of vision technologies. The steel volute of a commercial pump is replaced with a similar volute made in acrylic glass, which allows recording the motion of textiles inside the pump. Recordings are made at four different operating points to investigate the influence of rotational speed of the impeller and flow?rate on the passage of textiles through the pump. The experiments show that the textiles flow rapidly through the pump when the pump is operated near the best efficient point for both high and low impeller speed. The textiles tend to stay inside the pump when the pump is operated at part load for both low and high impeller speed.?At?low impeller speed,?the textiles often stick to the tongue in the pump casing. At higher impeller speed,?the textiles flow multiple rounds in the volute. For fail-safe operation,?it is recommended not to operate waste water pumps far away from the best efficiency point.

Artificial Water Channel that Couples with Cell Protrusion Formation

In natural systems,water transport across the cellular plasma membranes is mainly mediated by naturally occurring channel protein aquaporins(AQPs),which lead to a series of important physiological functions including cell migration.The construction of artificial analogs of the natural AQPs would generate a new strategy for treating AQP-related diseases.In this report,an artificial water channel has been developed from a unimolecular tubular molecule,which featured structural encapsulation of a single-file water wire composed of oppositely orientated dipolar water molecules.This AQP-like structure endowed the artificial channel in living cells with AQP-like water permeability and selectivity.Interestingly,the artificial channel coupled with cell protrusion formation by mediating water transmembrane transport,leading to cell shape change and migration acceleration.The artificial channel-facilitated cell migration showed application in enhancing in vivo healing of traumatic injury.

Artificial Water Channels—Progress Innovations and Prospects

The design of artificialwater channels(AWCs)aims to mimic natural proteins that effectively mediate the selective transport of water across the bilayer and artificial polymeric membranes.Currently,impressive progress on synthetic backbones,including selfassembled channels,helical unimolecular,and other functional organic molecules,has been made to provide artificial alternatives and applications in real systems for promising product development.In this review,several synthetic channels exploited during the last fewyears are summarized according to their backbone architecture for water transport and ion transport respectively,showing their potential as natural transporter analogs and the importance of AWCs for industrial,environmental,and medical applications.

Bioinspired and biomimetic membranes for water purification and chemical separation: A review

Bioinspired and biomimetic membranes that contain biological transport channels or attain their structural designs from biological systems have been through a remarkable development over the last two decades.They take advantage of the exceptional transport properties of those channels,thus possess both high permeability and selectivity,and have emerged as a promising solution to existing membranes.Since the discovery of biological water channel proteins aquaporins(AQPs),extensive efforts have been made to utilize them to make separation membranes–AQP-based membranes,which have been commercialized.The exploration of AQPs’unique structures and transport properties has resulted in the evolution of biomimetic separation materials from protein-based to artificial channelbased membranes.However,large-scale,defect-free biomimetic membranes are not available yet.This paper reviews the state-of-the-art biomimetic membranes and summarizes the latest research progress,platform,and methodology.Then it critically discusses the potential routes of this emerging area toward scalable applications.We conclude that an appropriate combination of bioinspired concepts and molecular engineering with mature polymer industry may lead to scalable polymeric membranes with intrinsic selective channels,which will gain the merit of both desired selectivity and scalability.

Corrosion performance,corrosion fatigue behavior and mechanical integrity of an extruded Mg4Zn0.2Sn alloy

Magnesium alloys are promising as load bearing components.They are inevitably exposed to cyclic loading and corrosive environment in actual service,which can consequently result in corrosion fatigue failure and loss of mechanical integrity of the material.Therefore,in the present study,the corrosion behavior,corrosion fatigue performance and mechanical integrity of an extruded Mg4Zn0.2Sn(wt.%)alloy were thoroughly studied in two corrosive electrolytes.Strong localized corrosion occurred when the alloy was immersed in deionized water based sodium chloride(NaCl)solution.The poor corrosion resistance of the alloy resulted in a fast deterioration of the tensile properties after pre-exposure to salt spray and a poor fatigue resistance in deionized water based NaCl solution.In comparison,the active dissolution of the substrate was sufficiently suppressed in artificial tap water based NaCl solution due to the formation of highly protective corrosion product layers.This consequently conferred longer fatigue life on the alloy in the electrolyte.Our results emphasized the influence of corrosion on the fatigue behavior and tensile properties of magnesium alloys.

Theoretical and numerical investigations of wave resonance between two floating bodies in close proximity

A simple theoretical dynamic model with a linearized damping coefficient is proposed for the gap resonance problem, as often referred to as the piston mode wave motion in a narrow gap formed by floating bodies. The relationship among the resonant response amplitude and frequency, the reflection and transmission coefficients, the gap width, and the damping coefficient is obtained. A quantitative link between the damping coefficient of the theoretical dynamic model（ε） and that devised for the modified potential flow model（μ_p） is established, namely, μ_p=3πεω_n/8 （where ω_n is the natural frequency）. This link clarifies the physical meaning of the damping term introduced into the modified potential flow model. A new explicit approach to determine the damping coefficient for the modified potential model is proposed, without resorting to numerically tuning the damping coefficient by trial and error tests. The effects of the body breadth ratio on the characteristics of the gap resonance are numerically investigated by using both the modified potential flow model and the viscous RNG turbulent model. It is found that the body breadth ratio has a significant nonlinear influence on the resonant wave amplitude and the resonant frequency. With the modified potential flow model with the explicit damping coefficient, reasonable predictions are made in good agreement with the numerical solutions of the viscous fluid model.