水雷声引信系统海试考核方法探讨

对水雷声引信系统海上试验的考核方法进行了探讨,重点介绍了战技指标的概念和定义,并针对主要指标要求,分别详细介绍了考核评判标准。     

Effect of Drying on Particle Size and Sensitivities of Nano hexahydro-l,3,5-trinitro-l,3,5-triazine

Nano hexahydro-l,3,5-trinitro-l,3,5-triazine （RDX） was prepared using a bi-directional rotation mill and dried under different conditions （liquid, temperature and drying）. It shows that the samples cake seriously and the particles grow up obviously by ordinary drying in different liquids at 70 ℃, which occurs again after vacuum drying. With the increase of temperature, the degrees of caking and aggregation are enhanced. Well dispersed sample maintaining constant particle size is extracted by supercritical drying, especially freeze drying. Furthermore, the me- chanical sensitivities of I-RDX, O-RDX and F-RDX, of which the average sizes are 88.03 μm, 15.32 μm and 0.16 μm, respectively, are evaluated. Compared with I-RDX, the friction, impact and shock sensitivities of O-RDX are slightly lower. However, the friction, impact and shock sensitivities of F-RDX are reduced by 30%, 99.0% and 59.9%, respectively.     

飞机投弹出舱过程自动记录装置

介绍一种飞机投弹出舱过程自动记录装置。该装置没有对飞机的机械接口和电气接口进行任何改变,只需利用飞机现有挂弹架的挂弹钩接口安装设备,通过光敏开关感应光线强弱变化,判断飞机武器舱门是否打开,从而自动触发高速摄像机拍摄,完成飞机投弹出舱过程的记录任务。     

Biocompatible electrospun tactic poly(methyl methacrylate) blend fibers

Uniform and beads free fibers of pristine syndiotactic PMMA (s-PMMA), isotactic PMMA (i-PMMA), and their blends in the ratio of s:i = 3:1, 1:1 and 1:3 were successfully prepared using the electrospinning technique. The tactic PMMA blend fibers showed unique thermal stability and glass transition temperatures compared to their pristine counterparts. An interesting endotherm peak was observed for the s:i = 1:3 electrospun fibers, which might indicate a complex formation between the two tactic PMMAs. Systematic surface functionalities study by attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) revealed the interactions between these two tactic PMMAs. Biocompatibility of tactic PMMA and their blend fibers was first time comparably investigated using HeLa as the model mammalian cell line; an intriguing observance was first revealed that the blend fibers showed better biocompatibility than both pristine ones, though the behind mechanism is not well understood yet.     

TiB2 Powders Synthesis by Borothermal Reduction in TiO2 Under Vacuum

TiB₂ powders were synthesized by borothermal reduction in nanoscale TiO₂ with boron under vacuum. Reaction processes were investigated, and the effect of by‐product B₂O₃ was evaluated. Results showed that TiO₂ was firstly reduced by boron to form TiBO₃ and Ti₂O₃, and then to produce TiB₂ and B₂O₃ with increasing temperature. The reaction processes of TiB₂ powders synthesis included two‐step reduction in TiO₂ by boron and the removal of B₂O₃. The presence of B₂O₃, which was previously reported as the most important factor in promoting the coarsening of ZrB₂ and HfB₂ powders by borothermal reduction, did not lead to significant coarsening of TiB₂ powders. Due to the minor effect of B₂O₃, TiB₂ powders with small particle size and low oxygen content could be prepared by direct heat treatment of TiO₂ and boron at 1550°C under vacuum for 1 h. The particle size and oxygen content of synthesized TiB₂ powders were ~0.9 μm and ~1.7 wt%, respectively.     

A Decomposition Route for Synthesis of Al2O3 Crystal and its Applications as Thermal Conductivity Filler

Platelike α‐Al₂O₃ powder was obtained at 850°C by thermal decomposition of ammonium aluminum carbonate hydroxide precursor, which was treated by hydrofluoric acid. The results showed the decomposition of the as‐prepared precursors experienced via three steps, adsorption of physical water, dehydration of crystalline water, and decomposition of the precursor, and the activation energies of the above three steps were calculated using the Coats–Redfern method. Meanwhile, the intermediate of (NH₄)₃AlF₆ obtained played an important role in decreasing activation energy of the decomposition and phase transformation. Moreover, the thermal conductivity of the epoxy resin filled with platelike alumina was improved obviously.     

Pipelining image compositing in heterogeneous networking environments

Because of intensive inter‐node communications, image compositing has always been a bottleneck in parallel visualization systems. In a heterogeneous networking environment, the variation of link bandwidth and latency adds more uncertainty to the system performance. In this paper, we present a pipelining image compositing algorithm in heterogeneous networking environments, which is able to rearrange the direction of data flow of a compositing pipeline under strict ordering constraint. We introduce a novel directional image compositing operator that specifies not only the color and α channels of the output but also the direction of data flow when performing compositing. Based on this new operator, we thoroughly study the properties of image compositing pipelines in heterogeneous environments. We develop an optimization algorithm that could find the optimal pipeline from an exponentially large searching space in polynomial time. We conducted a comprehensive evaluation on the ns‐3 network simulator. Experimental results demonstrate the efficiency of our method. Copyright © 2016 John Wiley & Sons, Ltd.     

Injury Mechanisms of Lactic Acid Bacteria Starter Cultures During Spray Drying: A Review

Lactic acid bacteria (LAB) starter cultures can be processed by many drying techniques, among which spray drying has great potential. However, injuries of LAB during spray drying lead to a low survival rate. The microbial injuries of LAB during spray drying are specifically induced by dehydration inactivation, thermal inactivation, and balance between the two. To reduce the drying temperature, new drying techniques based on spray drying were tried; that is, low-temperature vacuum–spray drying and spray–freeze drying.     

Ca~(2+)和Mg~(2+)对石英浮选的影响研究

以含稀土磷矿石中的脉石矿物石英为研究对象,进行纯矿物浮选试验、Zeta-电位测试及溶液化学计算,研究Ca2+和Mg2+对石英浮选的影响。纯矿物浮选试验结果表明,捕收剂HAY浮选石英较为适宜的用量为0.5g/L。Ca2+对捕收剂HAY浮选石英具有一定活化作用,随着离子质量浓度增大而增大。低质量浓度Mg2+对捕收剂HAY浮选石英也具有一定活化作用,但当Mg2+达到一定质量浓度后,反而对捕收剂HAY浮选石英产生抑制作用。石英Zeta-电位测试和溶液化学计算结果表明,Ca2+和Mg2+活化捕收剂HAY浮选石英的主要活性成分为羟基络合物Ca(OH)+。     

细粒鲕状难选胶磷矿选别试验研究

本研究磷矿样主要为细粒鲕状胶磷矿,属于难选磷矿,通过擦洗试验、正浮选试验和反浮选试验,确定了反浮选试验流程是回收该磷矿的有效手段。在原矿品位为23.15%时,采用反浮选可以得到精矿品位为27.80%,回收率为76.85%的较好指标。