Improved moving least squares algorithm for directed projecting onto point clouds

Directed projection is a key issue in many point-based techniques in geometric modeling, computer graphics, and computer vision. This paper proposes a new point-based directed projection method in the frame of moving least squares (MLS) projection where the reference plane is determined by approximating its normal using weighting least squares method, and the weighting value, on every neighboring points is determined according to the distance from the point to the projection ray. At every optimal step, the normal is calculated from updated neighborhood to relocate the reference plane, and check the variation in energy. The resulting solution is obtained with the local minima of the energy. Comparing with the existing directed projection algorithm, the proposed method is more robust and efficient, especially for the surfaces with complex profiles. To demonstrate the valid of the proposed approach and its application in part manufacturing, several numerical experiments have been presented and the results show that it is promising.     

Inhibition of copper corrosion in sodium chloride solution by the self-assembled monolayer of sodium diethyldithiocarbamate

Sodium diethyldithiocarbamate (DDTC) self-assembled monolayer (SAM) on copper surface has been investigated by SERS and EDS and the results show that DDTC SAM is chemisorbed on copper surface by its S atoms with tilted orientation. Corrosion inhibition ability of DDTC SAM was measured in 3% NaCl solution using electrochemical methods. The impedance results indicate that the maximum inhibition efficiency of DDTC SAM can reach 99%. Quantum chemical calculations show that DDTC has relatively small ΔE between HOMO and LUMO and large negative charge in its two sulfur atoms, which facilitates the formation of a DDTC SAM on copper surface.     

淮南矿区煤层气民用补充气源方案探讨

将矿井瓦斯作为淮南矿区居民民用燃气是矿井瓦斯利用的主要途径。针对淮南矿区煤层气产业化发展的需求，从互换性、安全性和实用性三方面对天然气混合气作为煤层气补充气源的可行性进行分析，指出天然气混合气与煤层气具有互换性，可作为补充气源，并提出了具体实施方案。     

Temperature and strain rate dependence of deformation behavior of Zr65Al7.5Ni10Cu17.5

In this work, the effects of temperature and strain rate on the deformation behavior of Zr₆₅Al_7.5Ni₁₀Cu_17.5 bulk metallic glass (BMG) were investigated. It was found that both temperature and strain rate had a significant influence on the deformation behavior of the BMG. The alloy exhibited Newtonian behavior at low strain rates but showed non-Newtonian behavior at high strain rates in the supercooled liquid region. However, the crystallization occurred slightly at a strain rate of 2 × 10^?4 s^?1 at the temperature of 693 K that is lower than the crystallization temperature Tx of Zr₆₅Al_7.5Ni₁₀Cu_17.5 BMG. The deformation mechanisms were discussed in terms of the transition state theory based on the free volume model.     

Fabrication and Magnetic Properties of Fe<Subscript>65</Subscript>Co<Subscript>35</Subscript>–ZnO Nano-Granular Films

A series of nano-granular films composed of magnetic metal (Fe₆₅Co₃₅) granules with a few nanometers in size and semiconductor oxide (ZnO) have been fabricated by a magnetron sputtering method, and excellent soft magnetic properties have been achieved in a wide metal volume fraction (x) range for as-deposited samples due to the exchange coupling between FeCo granules (a ferromagnetic interaction in nano-scale). In a wide range (0.53 < x < 0.71), the films exhibit coercivity H _C not exceeding 15 Oe, along with high resistivity. Especially for the sample with x = 0.67, coercivities in hard and easy axes are 1.43 and 7.08 Oe, respectively, 4πM _S  = 9.85 kg, and ρ reaches 2.06 × 10³ μΩ cm. The dependence of complex permeability μ = μ′ − jμ″ on frequency shows that the real part μ′ is more than 100 below 1.83 GHz and that the ferromagnetic resonance frequency reaches 2.31 GHz, implying the promising for high frequency application. The measured negative temperature coefficient of resistivity reveals that may be the weak localized electrons existing in samples mediate the exchange coupling.     

大悬挑钢结构雨篷的设计与施工

通过某具体工程,运用3D3S结构分析软件对大悬挑雨篷的结构计算进行分析并对施工的主要步骤进行介绍。结果表明该雨篷设计及施工能够满足结构安全及使用功能的要求。     

Chemical modification of ethylacetoacetate with ASB in aqueous medium

Ethylacetoacetate (EAA) was mixed with aluminum sec-butoxide (ASB) in aqueous medium. The molar ratio among aluminum sec-butoxide, water, and ethylacetoacetate was 1:200:1. Water diluted nitric acid was added into the mixture until it finally transformed into transparent solution. TEM analysis showed that the surfaces of the colloidal particles with EAA were not as clean as those without EAA, implying the formation of a surface modification layer around the colloidal particle. The IR spectra analysis revealed that with the addition of EAA two characteristic peaks of EAA at 1 731 cm⁻¹ and 1 642 cm⁻¹ associated with C=O stretching vibrations were red-shifted to 1 619 cm⁻¹ and 1 530 cm⁻¹, respectively, indicating the occurrence of the chemical modification reaction among the C=O bonds of EAA and the surface Al-OH bonds of the particles., Furthermore it was confirmed by UV spectra analysis that the UV absorption band of EAA underwent 26 nm of red-shift as a result of the formation of the six-membered ring of the complex between ethylacetoacetate and ASB. It was examined that the chemical modification could be photolyzed by the UV illumination with a wavelength shorter than 270 nm due to the excitation of π − π * transition in the complex. Funded by the Doctoral Fund of University of Jinan (No. XBS0812)