Advanced Materials Research Vols. 343-344

Abstract: Gallium Nitride (GaN) PIN betavoltaic nuclear batteries (GB) are demonstrated in our work for the first time. GaN films are grown on sapphire substrates by metalorganic chemical vapor deposition (MOCVD), and then GaN PIN diodes are fabricated by normal micro-fabrication process. Nickel with mass number of 63 (63Ni), which emits β particles, is loaded on the GaN PIN diodes to achieve GB. Current-Voltage (I-V) characteristics shows that the GaN PIN diodes have leakage current of 18 pA at -10V due to consummate fabrication processes, and the open circuit voltage of the GB is estimated about 0.14 V and the short circuit current density is 89.2nAcm^-2 . The relative limited performance of the GB is due to thick dead layer and strong backscattering of β particles, Which lead to less energy deposition in GB. However, the conversion efficiency of 1.6% and charge collection efficiency (CCE) of 100% for the GB have been obtained. Therefore, the output power of the GB are expected to greatly increase with thin dead layer and structural surface weakening the backscattering.

Abstract: In this paper, the removal behaviour of Zn²⁺ from aqueous solution by adsorption onto solidifying landfilled sludge and its mechanism were studied. The results showed that Zn²⁺ adsorption capacity reached optimum when initial pH was 3.0. When initial Zn²⁺ concentration was150mg/L, the removal efficiency could reach more than 90% with dosage of solidifying landfilled sludge being 6g/L. Moreover, the adsorption isotherm could conform to Freundlich equations best. The desorption ratio for adsorbed Zn²⁺ reached above 90% by HCl solution with pH value being 1.0, however, it was only about 10% despite of EDTA concentration. FTIR analysis showed that main site for Zn²⁺ adsorption onto solidifying landfilled sludge was Me-O group from metal oxide and hydroxyl group from fatty alcohol.

Abstract: The problems with underground service pipes are the regular session of accidents in city gas line network which is directly related to people's lives. However, there are potential risks with underground service pipe. The scientific and reasonable gas service pipe should be to minimize the accidents and easy to installed and guarantee the economical in the case of ensuring gas use. Comparing and analyzing the two ways frequently used in daily life from the aspect of pipe materiel and pipe laying methods, drawbacks of them are identified. Finally, the main use of PE pipe is recommended and measures to transform are proposed, which eliminate the security risk after improvement, and obtain the economic benefit in the long term.

Abstract: Scoria which is a kind of natural light bone material was selected as the reaction media of permeable reactive barrier (PRB) in this study. The aim is to investigate the scoria’s adsorption kinetics, adsorption isothermal model and reaction mechanism during the process of its purification to petroleum hydrocarbon contaminated groundwater. Parallel batch tests showed that the removal efficiency of TPH (total petroleum hydrocarbons) was 87.91% when the experiment time to 90 min. The adsorption of scoria to TPH was well fitted by the pseudo-second order kinetic equation and Langmuir isotherm, with the kinetic formula t/Qt=2.3082t+20.692 and the isothermal equation 1/Qe=6.5644/Ce+0.0007, respectively. It was also shown that the apparent maximum adsorption capacity of scoria was 1.7g/g. Analysis results from SEM, IR, XRD and other methods indicated that scoria’s composition and its material structure were closely related to the remediation mechanism of petroleum hydrocarbon contaminated groundwater. However, it was not only physical adsorption but also chemical adsorption happened during scoria’s adsorption process. The results could provide a reliable reaction medium for PRB technology which used in petroleum hydrocarbon contaminated groundwater remediation.

Abstract: This study was conducted to explore the effect of CuO nanoparticles (NPs) on the cell membrane permeability and its exclusion from cells. Human A549 lung cells were exposed to 5mg/L and 15mg/L CuO NPs. Cell membrane permeability was evaluated in 2h and 4h. After 4 hours exposure, the membrane was damaged. Exclusion of copper from cells after 24h exposure with 5mg/L and 15 mg/L CuO NPs are time and dose dependent. And the cell viability was resumed gradually. It is concluded that CuO NPs could induce cytotoxicity, and destroy the membrane integrity. One detoxify mechanism was the exclusion of excessive copper from cells themselves.

Abstract: With the rapid development and versatile applications of nanotechnology, a large quantity of nanoparticles (NPs) has been released into the environment. It has been one of the most popular studies that concerning about the toxic effect of NPs on the organism of the total environment. This paper reviews the new results that reflect the impact of NPs on the algae. It also concludes the new researches from the fate and behaviors of the NPs, the ecotoxicology to the algae and the possible mechanism. Finally, there is an expectation concerning the study of toxicity of NPs to the algae, and propose what should investigate in future.

Abstract: Based on the characteristic of cyclic softening of the quenched and tempered Carbon steel 45, a cyclic plastic constitutive model was proposed to describe the cyclic behavior under symmetrical and unsymmetrical strain cycling with different strain amplitudes. In this model, the phenomenon of the decrease of the up yield limit stress with the increase of strain in the initial 1/4 cycle was taken into account. The proposed evolution equations of the yield size and backstress can simulate the cycling softening under symmetrical and unsymmetrical strain cycling well. The results indicated that either the simulated shape of the cyclic softening hysteresis loops or the evolution of stress amplitude with the increase of the cyclic number during the low cycle fatigue coincides with the experimental ones very well.

Abstract: On the basis of summarizing the predecessors' achievements，according to the basic theory of rock mechanics, fluid mechanics in porous medium, geologic mechanics, calculated mechanics and fluid-solid coupling seepage, a mathematical and numerical model of seepage field and stress field coupling is developed in porous medium and the LiuNan blocks of JiDong oilfield wells.based area single phase Stress Field / Seepage Field in solving with the method of finite element software ANSYS, Contrast analysis of LiuNan blocks Coupling around of Field / Seepage Field is the change of average stress and total displacement. As can be seen from Table 3, after coupling the value of average stress and total displacement are greater than before coupling.So from figure 2 know than it is important meaning for used to solve practical engineering problems.

Abstract: We studied the relationship of the superlattice structure with the doping efficiency in detail by semi-classic calculation and follow experiment. The results show that period length of about 9nm and Al content of 30% is optimal. The Hall, AFM and PL measurement show that the best annealing temperature under atmosphere is about 540°C to 580°C. Finally we obtained the sample with resistivity of 0.31Ω·cm. It can be used for fabricating p type ohmic contact and active layer for blue LED.

Abstract: Polarization curves, corrosion potential, scanning electron microscopy (SEM) were adopted in order to investigate the corrosion behaviors of B10 under the combination action of anaerobic SRB and facultative anaerobic V.natriegens. The characteristics and mechanisms of microbial corrosion action in sea water were analyzed in this paper. The results show that the existence of marine microorganisms accelerates the corrosion process of B10; SRB in the mixed microbe medium plays a leading role; the combined action of SRB and V.natriegens influences the matrix surface reunion phenomenon seriously and prone to pitting corrosion. Furthermore, this investigation indicates that the affectability of microbial corrosion of the base metal can be shown as follows: SRB > Mixed bacteria > V.natriegens > Sterile.