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Superplastic Pb-Sn alloys were produced via tube high-pressure shearing (t-HPS), in a single step starting from elemental solid bulks. A Pb-40 wt% Sn alloy showed an exceptional superplastic elongation as high as ∼1870% at a strain rate of 1.0 × 10 −3 s −1 at room temperature, thereby elevating the optimum strain rate for maximum elongation under these conditions by more than one order of magnitude over conventional cast Pb-Sn alloys. This unprecedented room temperature superplasticity is attributed to the equiaxed grains having uniform sizes of the order of one micrometer, and in particular to the well-mixed domains of Pb and Sn in nearly equal proportions. This microstructure cannot be attained in cast eutectic or hypoeutectic alloys through conventional thermomechanical processing, but instead it is a direct outcome of t-HPS-generated compositional patterning at room temperature.

The Lailishan deposit is an important tin deposit that is genetically associated with an Early Eocene biotite granite in the western Yunnan metallogenic belt in the Sanjiang region, SW China. This study reports new zircon U–Pb ages and Hf isotopic data, whole–rock elements, mica Ar–Ar age and C–H–O–S–Pb isotope for the Lailishan Sn deposit. The mineralization–related biotite granite crystallized during the Early Eocene (50.5 Ma), with its zircon eHf(t) values ranging from −11.5 to −7.6 and two–stage Hf model ages (T DM2 ) ranging from 1.60 to 1.85 Ga. The rocks are peraluminous with A/CNK values of 0.99–1.08. The granites display high Si, Al and K contents but low Mg, Fe and Ca contents. The rocks show flat chondrite-normalized REE patterns with strong Eu negative anomalies. These characteristics indicate that the magma originated from a continental crustal source. The hydrothermal muscovite exhibits an Ar–Ar plateau age of 50.4 ± 0.2 Ma. The δ 18 O and δD values of hydrothermal quartz from the deposit range from −7.32‰ to 4.01‰ and from −124.9‰ to −87.1‰, respectively. The δ 13 C PDB and δ 18 O SMOW values of calcite range from −11.3‰ to −3.7‰ and from +2.2‰ to +12.7‰, respectively. The sulfur isotopic compositions (δ 34 S V–CDT ) range from +3.3‰ to +8.6‰ for sulfide separates, and the lead isotopic ratios 206 Pb/ 204 Pb, 207 Pb/ 204 Pb and 208 Pb/ 204 Pb range from 18.668 to 18.746, from 15.710 to 15.743 and from 39.202 to 39.295, respectively. These isotopic compositions are similar to those of magma–derived fluids, indicating that the ore–forming fluids and materials mainly originated from magmatic rocks with some input from meteoric water. This evidence suggests that the tin mineralization is closely linked to the Lailishan I–type granites. In combination with previous data, it is proposed in this study that widespread early Eocene magmatism resulted from the slab breakoff of the subducting Neo-Tethyan slab at ca. 55 Ma.

Recently, with the increasing strength of attracting business and investments in Liaoning coastal area or big cities’ suburbs (counties), a large number of industrial and mining enterprises have shifted to rural areas. The rural areas’ power load is growing rapidly, but at the same time, many power sites such as 66kv substation, 10kv transmission line, and low-voltage distribution area have occurred different levels of “low voltage”, which affect the daily life and production of native residents. From 2011, Liaoning Electric Power Co., Ltd. has applied the third generation of dynamic reactive power compensation technology—SVG to control the “low voltage” of rural network, which has fast speed and strong compensation. And as a consequence, there is good social and economic benefit.

sensor used in DC ground fault detection system according to measurement method can be divided into low frequency AC signal detecting and DC signal detecting of leakage current . It greatly affect the accuracy of the earth fault signal because of the existence of capacitance in the detecting of low frequency AC signal and it doesnt have online measurement DC current sensor in the market when we want to measure load leakage current. Caliper DC ammeter cant meet the requirements in DC system ground fault diction in terms of resolution, accuracy, range, on-line installation and on-line measurement.

Polycrystalline silicon film was directly fabricated at 200°C by the conventional plasma enhanced chemical vapour deposition method from SiCl4 with H2 dilution. The crystallization depends strongly on the deposition power. The maximum crystallinity and the crystalline grain size are over 80% and 200-500 nm, respectively. The results of energy dispersive spectroscopy and infrared spectroscopy measurements demonstrate that the film is mostly composed of silicon, without impurities such as Cl, N, C and bonded H. It is suggested that the crystallization at such a low temperature originates from the effects of chlorine, i.e., in-situ chemical, etching, in-situ chemical cleaning, and the detachment of bonded H.

The effect of hydrogen dilution was investigated on polycrystalline silicon formation using radio frequency excitation SiH4/ H2 plasma. The hydrogen dilution reduces the growth rate of the a-Si : H films. The dark conductivity of the a-Si : H films increases with increasing H2 dilution. The dark conductivity of the poly-Si films formed by recrystallization annealing of the a-Si : H film decrease with H2 dilution. The grain size, with X-ray diffraction spectroscopy and scanning electron microscopy images of the poly-Si films, is in reverse ratio to the H2 dilution.

The stability of pc-Si films under long-time illumination was studied. The films were fabricated at low temperature of 250degC by plasma-enhanced chemical vapor deposition technology from SiCl4 /H2. The light soaking for 720 min in vacuum was carried out using white light of an intensity of 100 mW/cm2. The light-induced effects were monitored by measuring the changes in the photoconductivity and dark conductivity. The experimental results indicate that light-soaking degradation phenomenon doesn't exit in the pc-Si films, which almost appears in all a-Si films. During long-term light irradiation, the photoconductivity is increasing all along until saturation. The phenomenon is similar to the persistent photoconductivity effect observed in the a-Ge films. Furthermore, the light-induced changes of conductivity depend on hydrogen dilution ratio. The persistent photoconductivity effect appeared in pc-Si films maybe relate to the material microstructure. Comparing with amorphous silicon films, pc-Si films have high crystallinity. Besides, we think chlorine element plays a important role

Ball screw are widely used in the steering-gear of automobile, aero-mechanism, machine tools and precision instrument. Since the thread form is referred to as a Gothic arch, so it is difficult to measure the ball screw. The traditional screw measuring method is "three wire" method or "three ball" method. The weakness of these methods is that the measuring process is too complicated or the measuring precision is not high. We have developed an intelligent ball screw measuring instrument. The instrument can measure the ball center diameter of ball screw. Using a new measuring method("two wire and one ball" method), the instrument has high measuring precision, high reliability and it is easy to operate.The 8098 microcomputer system in the instrument can control the measuring process and accomplish data collecting and processing automatically. This measuring instrument can be used on the production site for fast and precise measurement of ball screw.

Polycrystalline silicon films were prepared from SiCl4 diluted with hydrogen by plasma-enhanced chemical vapor deposition at a low temperature of 250℃. The effect of hydrogen dilution on their structure and optical properties were investigated. It was found that the effect of hydrogen on the growth behavior of the films deposited using SiCl4+H2 are completely different from that of using SiH4/H2. The crystalline fraction increases with decreasing the hydrogen dilution ratio R and reaches a maximum value of 85% at a low hydrogen dilution. However, further decreasing hydrogen dilution ratio leads the crystallinity to deteriorate and a phase transition between microcrystalline silicon and amorphous silicon is observed. The optical band gap gradually decreases from ～1.5eV to ～1.2eV and then increases up to 1.8eV with the decrease of the hydrogen dilution ratio. The deposition rate initially increases and then decreases with decreasing hydrogen dilution ratio, and no film is formed by using pure SiCl4. According to these results, we conclude that under the condition of optimum hydrogen dilution ratio, the enhanced crystalline fraction and the increase in grain size are attributed to the Cl radicals which play important roles in the low-temperature growth of crystalline silicon films.

We have studied the stability of amorphous silicon and polycrystalline silicon films under illumination. These films are prepared by plasma-enhanced chemical vapor deposition technology from SiH4/H2 and SiCl4/H2 separately. The exp eriment indicates that the light-soaking degradation phenomenon, which exists in almost all amorphous silicon films, does not appear in the polycrystalline sili con films. The light-dark conductivity of polycrystalline silicon films does not decrease but increase during light irradiation. Furthermore, the variance of co nductivity depends on hydrogen dilution ratio. It is suggested that the persiste nt photoconductivity effect of polycrystalline silicon films may originate from the high crystallinity and the action of chlorine.