The Influence of Crystal Orientation on Vibration Characteristics of DD6 Nickel-Base Single Crystal superalloy Turbine Blade

Modeling of a nickel-base single crystal superalloy turbine blade which accounts for material orthotropy is carried out to investigate the influence of axial direction and randomness crystallographic orientation on the dynamic natural frequency. In this paper, the natural frequency of the blade is calculated by the finite element method based on the commercial software ABAQUS. The results show that the deviation of the axial directions has a significant effect on the lower frequency as well as on the higher frequency, while the randomness in crystallographic orientations has a great impact only on higher order frequency. It is necessary to take the crystal orientation into account as an optimized factor and the variation of the vibration characteristics can be predicted.     

3,4,5-三羟基苯甲酸甲酯的抑菌特性及其对番茄青枯病的田间防治作用

[目的]为研制防治植物青枯病的新型农药,对3,4,5-三羟基苯甲酸甲酯进行了抑菌特性测定和田间防治试验。[方法]采用抑菌圈法测定供试化合物的稳定性以及没食子酸烷基酯类化合物对茄青枯拉尔氏菌的抑菌活性;通过大田防治试验,测定其对番茄青枯病的防治效果。[结果]该化合物具有很好的稳定性,酚羟基数目和烷基链长度同没食子酸烷基酯的抑菌活性密切相关;供试化合物可有效降低番茄青枯病发病率。[结论]该化合物具有开发为植物青枯病防治药剂的潜力。     

不锈钢酸洗污泥微波场中升温特性的研究

本文就酸洗污泥微波场中的升温特性进行了系统研究,旨在为探求酸洗污泥微波辐射深度脱水新工艺提供理论依据.结果表明,酸洗污泥干泥在微波场中的升温特性为先缓慢升温至拐点温度后开始快速升温;酸洗污泥湿泥在微波场中的升温特性为先快速升温至110℃左右后开始缓慢升温,直至水分蒸发完才出现拐点温度并开始快速升温.     

Synthesis of morphology-controlled mesoporous transition aluminas derived from the decomposition of alumina hydrates

Aluminum hydroxides were synthesized through the acidification of sodium aluminate solution using single organic diester or diacid as pH adjustor and aluminum chelating agent. The obtained alumina hydrates are investigated by XRD, SEM, IR and TG. Bayerite firstly formed at room temperature, and its morphology greatly varied with the pH adjustors used, which probably attributes to different kinetics of the acidification. The bayerite can evolve to gibbsite and boehmite after the hydrothermal treatment at 100 °C and 145 °C, respectively, where these alumina hydrates show diverse morphologies. After the calcination, these alumina hydrates of bayerite, gibbsite and boehmite could pseudomorphically transform to the corresponding η-, χ- and γ-aluminas, respectively, exhibiting different structural and textural properties. Interestingly, the transition aluminas derived from the aluminum tri-hydroxides, bayerite and gibbsite, both display locally organized mesopores, while no such meso-structure can be observed in γ-alumina obtained from the aluminum mono-hydroxide, boehmite. The changes of bayerite during calcination are investigated detailed. The dehydration of non-porous bayerite accompanied with the formation of meso-structured transition aluminas, where the meso-structure becomes more and more clearly defined and pore size expands with the calcination temperature increasing.     

An Information Hiding Algorithm Based on Bitmap Resource of Portable Executable File

An information hiding algorithm is proposed, which hides information by embedding secret data into the palette of bitmap resources of portable executable （PE） files. This algorithm has higher security than some traditional ones because of integrating secret data and bitmap resources together. Through analyzing the principle of bitmap resources parsing in an operating system and the layer of resource data in PE files, a safe and useful solution is presented to solve two problems that bitmap resources are incorrectly analyzed and other resources data are confused in the process of data embedding. The feasibility and effectiveness of the proposed algorithm are confirmed through computer experiments.     

Fault Prediction Based on the Kernel Function for Ribbon Wireless Sensor Networks

There exist several applications of wireless sensor networks in which the reliable operation can be crucial. Fault prediction is a critical problem in reliability theory for ribbon wireless sensor networks (RWSNs). Accurate fault prediction can effectively improve the availability of the WSNs system. In this paper, we evaluated the network performance for RWSNs, studied the basic theory of kernel functions, proposed a new failure prediction method based on kernel function, and selected the radial basis function as kernel function failure prediction models from two aspects of node hardware failures and network failures for fault prediction. Theoretical evidence and experimental results have shown that the proposed algorithmic prediction method has higher accuracy of 12 and 15% than that of GRNN and PNN respectively. Finally, we provided extensive numerical results to demonstrate the usage and efficiency of the proposed algorithms and complement our theoretical analysis.     

Preparation of ractopamine-tetraphenylborate complexed nanoparticles used as sensors to rapidly determine ractopamine residues in pork

In this work, we reported a simple, fast, and sensitive determination of ractopamine (RAC) residues in pork by using novel ractopamine-tetraphenylborate complexed nanoparticles (RT NPs) as sensors. The prepared RT NPs exhibited a fast response time of 10 s, a wide linear range from 0.1 to 1.0 × 10⁻⁷ mol/L, and a very low detection limit of 7.4 × 10⁻⁸ mol/L. The prepared sensor also presents a high selectivity for ractopamine under different pH conditions ranged from 2.85 to 7.18. These results reveal that the fabricated RT NPs can be used as efficient electrochemical sensors to determine ractopamine in animal productions.