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Four typical functional zones ,i.e. traffic zone, commercial zone, industry zone and residential zone were selected in Nanjing city for street dust sampling .In each zone and site, dust samples were randomly collected for five times. The total heavy metals were determined by atomic absorption spectrometry. And the concentration enrichment ratio (CER) was used to assess the degree of heavy metal contamination...
In the process of producing copper bar, because of the cast copper billet, rolling equipment, rolling process and other reasons, the surface of copper bar appear some defects such as crack, scarring, roller printing, scratches, holes, scales, pitting, and so on. These deficiencies not only affect the appearance of the product, but more importantly reduce the product's corrosion resistance, abrasion...
The efficiency of electrokinetic remediation of Cu contaminated groundwater was researched by means of experiments for the complicated remediation of groundwater contaminated by typical heavy metal in this paper, and migration and variation characteristics of Cu was analyzed too. The experimental results indicated that the pH value varied obviously during the electrokinetic remediation because of...
There are a great many of solid refuse including mining abolish stone, wall rocks, tailings and so on. Which have polluted soil, water, air and ecological environment. Its comprehensive utilization has already caused the extensive attention. It is very necessary for the comprehensive utilization evaluation, which makes government decision more reasonable. In this paper, the tailing comprehensive utilization...
Heavy metals Zn, Cu, Cd, Ni, Pb and Mn in the compressed sludge from Shenyang Northern Sewage Treatment Plant were removed by bioleaching. The results showed that: the treatment cycle of bioleaching was about 4d, water should be timely separated from sludge; After the treatment of bioleaching, the content of heavy metals in compressed sludge were below that of control standards for pollutants in sludge...
Contents of colloidal trace metals(1kD~1μm) in Meiliang Bay, an algal-bloom bay of Taihu Lake, and Gonghu Bay, a macrophytes dominanted bay of Taihu Lake, were investigated in April by using cross-flow ultrafiltration (CFF) technique. In each sampling site, 20 L surface water was pumped and filtrated by 63 μm nylon sieve. The filtered water was carried to laboratory in 2 hours, prefiltrated by 1μm...
The relation between minimum thickness of cut (MTC) and the extreme machining accuracy attainable for a specific cutting condition by Atomic Force Microscope (AFM) has been discussed. A mechanical model was used to describe qualitatively the minimum thickness of cut during nanometric cutting process. Mechanical response of aluminum and copper on nanoscratching has been studied. The analysis of the...
The relation among electronic structure, chemical bond and thermoelectric property of Ca3Co2O6 and Cu-doped is studied by first-principle theory. The results indicate that the highest valence band (HVB) and the lowest conduction band (LCB) are mainly contributed from Co3d, Cu3d and O2p atomic orbitals and that 1D Co-O chains along c axis play important role in electric property of Ca3Co2O6 and Cu-doped...
On the basis of studying inter-thermal performance of U-tube solar collector, the transient efficiency and efficiency factor were got. As for analyzing the thermal performance of the collector from different angles, two models were developed. By using numerical method each part of the collector were got. Furthermore, by weighted least square method, the instantaneous efficiency of solar collector...
Most classification studies are done by using all the objective data. It is expected to classify objects by using some subsets data effectively. A rough set based reduct is a minimal subset of features, which has almost the same discernible power as the entire features. Here, we propose multiple reducts which are followed by the k-nearest neighbor with confidence to classify documents with higher...
This paper introduces a concept for a reliable and miniaturized power control unit (PCU). With this PCU, an electro-mechanical actuator (EMA) is controlled. This EMA is intended to be used in a swashplateless helicopter control system. As this is a safety relevant part of the helicopter, the PCU needs to work reliably under challenging ambient and operating conditions. At the same time, the whole...
In this study, total of 261 soil profiles were reported to investigate the Cu spatial distribution and vertical variation in Guangdong province using geography information system (GIS) and geostatistics. Findings indicated that the Cu geometric mean concentration of 11.2 mg/kg in surface soils is lower than those in China, which ranged from 0.12-98 mg/kg. The influence of soil properties on Cu concentration...
Recently, there has been great interest in the multicast service where a common content such as video streaming and TV program is intended for multiple users. However, while receiving the common message, the users may also wish to receive their personal messages. Therefore, in this paper, we consider a multiple-antenna base station communicating with two single-antenna users and there are a common...
Management of traffic incident is an essential part of emergency management. Impact analysis of incident becomes more and more important in the operation of Intelligent Traffic System. This paper uses flow data collected from loop detectors to analyze the impact of incident in urban traffic system. A complex network model using correlation coefficient as the edge weight is constructed. Then, the random...
We present the performance of a piezo-actuated compliant micromirror made of single crystal silicon, which is assembled with a compliant displacement amplification mechanism made of copper. Both of those two parts are purely based on the elasticity and deformation of thin beams. The measurement results reveal that our optical device achieves the specified function as a linear optical scanner, and...
In this paper we consider the problem of scheduling family jobs on a parallel-batching machine under on-line setting, Our objective is to minimize the maximum completion time of the jobs (makespan). A batch processing machine can handle up to B jobs simultaneously. The jobs that are processed together form a batch, and all jobs in a batch start and complete at the same time. The processing time of...
Image motion compensation is significantly important for aerial camera photograph. To execute the compensation, we must determine the image motion exactly. This paper proposes a method of real-time image motion measurement for panoramic aerial cameras based on image processing using a hybrid system. Two cameras are simultaneously used in the hybrid system. One main linear CCD for imaging, while the...
Electrodes with nano-scale gaps have been fabricated using metallic nano-wires, derived via milling of thin films with focused ion beam (FIB) and passing current ~1012A/m2. Their I-V characteristics measured at a pressure ~10-6 mbar are shown to follow Child-Langmuir law or Fowler-Nordheim field emission depending upon the gap.
A thermodynamic mechanism has been developed to explain the formation of aligned cupric oxide (CuO) nanowires synthesized by thermal oxidation of copper substrates at different conditions. The 1D morphology and temperature dependence of parameters of nanowires were explained.
Firstly, to minimize the ripples of the electric magnetic torque and flux linkage produced in the conventional direct torque control (DTC) system for permanent magnet synchronous motors (PMSM); this paper proposes a expected space vector modulation (ESVM) strategy of DTC. The expected voltage was produced by SVM. PI controller was used in flux and torque controller, instead of hysteresis comparator...
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