Narrow Results

Problems that cumber the development of the laser propulsion in atmosphere and vacuum are discussed. Based on the theory of interaction between high-intensity laser and materials, such as air and water, it is proved that transport in a water environment can be impulsed by laser. The process of laser propulsion in water is investigated theoretically and numerically. It shows that not only the laser induced plasma shock wave can be used, but also the laser-induced bubble oscillation shock waves and the pressure induced by the collapsing bubble can be used. Many experimental results show that the theory and the numerical results are valid.

The presence of aqueous solution is inevitable in complex systems involving biological and material components and could affect the interaction between them substantially. To properly simulate such an interaction system, it is necessary to quantitatively explore the effects and specific roles of the water environment on the material surface. In this work, a silica surface was adopted as an example to study the impact of water environment (144H₂O) on the structure and energetics using a self-consistent charge density functional tight binding/molecular dynamic method. First, we demonstrated that the silica surface in a vacuum involves a large deformation due to the formation of hydrogen bonds among the surface silanols; in contrast, the deformation is eased in water environment because water molecules could locate in between the silanols and form many hydrogen bonds with the silanols. Therefore, water molecules play an important role to maintain surface from not getting heavily deformed. Our work not only tested the feasible computational methodology of studying nanoscale large systems under water environment at a quantum-mechanical level of theory, but also provided clear evidence on the impact of water environment to the inorganic surface.

A zwitterionic glycine (zGLY) is adopted as an example to study the impact of water environment (310 H₂O molecules) on the molecular structure and energetics using a self-consistent-charge density-functional tight-binding theory based molecular dynamics (SCC-DFTB/MD) method. It is found that maximal eight hydrogen bonds could be formed simultaneously between eight water molecules and the zGLY. The ability of the COO^- terminal to adsorb water molecules is stronger than the terminal with respect to hydrogen bonding with more water molecules and exhibits lower adiabatic adsorption energies. The zGLY's intramolecular hydrogen bond appeared unpredictably, without involving any proton transfer and generally helpful for enhancing the system stability. Water molecules play an important role to stabilize the zwitterionic amino acids and restrain the proton migration from the to the COO⁻ group. Our results show that the SCC-DFTB/MD method could successfully describe geometry dynamical evolutions and energetics of biomolecules in a nanoscale simulation with the presence of a large number of water molecules. Our study not only verified the feasibility of a QM level methodology for describing the aqueous states of biochemical molecules, but also gave a clear evidence for the impact of water environment on amino acids.

Currently, rapidly locating relevant data sources and assembling the most appropriate data on the Internet is a tremendously difficult task for researchers. To address these issues, this paper proposes the development of a high availability ontology-based water environmental data retrieval and visualization system (OntoWE). The OntoWE prototypes have two significant features. Firstly, it establishes a water environment domain ontology to offer facilities to alleviate semantic heterogeneity and associate semantic information with the data retrieval process. Secondly, it embraces the capability of Service Oriented Architectures (SOA) and Silverlight to leverage the latest protocols of several open web service standards with the Managed Extensibility Framework (MEF). This system provides a centralized and easy-to-use interactive system which enables users to do a one-stop search, access and visualize different types of water data in a single environment. The feasibility and effectiveness of OntoWE system was demonstrated through several investigations about water quality data discovery and retrieval at basin scale in China.

The water environmental capacity is not only the basic foundation in objective management of water environment, but also the constraint condition for the planning of water environment and its surrounding environment. Dongjiang Lake is the location of strategic water resources reserves in Xiangjiang River Basin urban agglomeration, and the Dongjiang Lake Scenic Area is a national scenic area that combines the ecological and tourism functions. Based on the statistics of water environment pollution in Dongjiang Lake Scenic Area, this paper conducts quantitative research and analysis of its water environmental capacity, hoping to conduct phased control of target volume of pollution load into Dongjiang Lake Scenic Area and provide data support to various follow-up special plans in the scenic area.

The natural environment is the human made places of basic life substance and to human provide raw material production base, water is the most active factor in the natural environment, water environment directly affects the survival and development of human society. For in recent years, China's urban life water consumption increased year by year, and water resource is decreasing year by year, we analyze the Shaoxing water resource use to study a variety of water-saving technology, get conclusion by use of combining with the recycled water and rain water, in order to improve the water environment.