挤出机螺杆转速对马来酸酐官能化EVA性能的影响及其增韧研究

采用添加引发剂过氧化二异丙苯（DCP）和提高熔融挤出过程中双螺杆挤出机螺杆转速的机械力引发方法研究了马来酸酐（MAH）官能化乙烯一醋酸乙烯酯共聚物（EVA）的熔融挤出反应.研究了引发剂用量和螺杆转速对产物的接枝率和熔体流动速率的影响.结果表明,随着DCP用量的增加,产物接枝率出现峰值,而随着螺杆转速的增加,产物接枝率出现先下降后增大的变化,接枝产物的熔体质量流动速率（MFR）在螺杆转速达到300r/min时出现显著增大,在一定的配方条件下,通过改变螺杆转速,可以抑制EVA在接枝过程中的交联副反应,控制制得具有较高接枝率（0.29%～0.8%）和较好熔体质量流动速率（0.7～1.2g/10 min）的接枝产物（EVA-g-MAH）.力学性能测试表明,此复合引发接枝产物对尼龙66具有较好的增韧效果.     

Crystallography and Structure–Property Relationships in 2,2′,2″,2′′′,4,4′,4″,4′′′,6,6′,6″,6′′′‐Dodecanitro‐1,1′ : 3′1″ : 3″,1′′′‐ Quaterphenyl (DODECA)

X‐ray crystallographic study of 2,2′,2″,2′′′,4,4′,4″,4′′′,6,6′,6″,6′′′‐dodecanitro‐1,1′ : 3′1″ : 3″,1′′′‐quaterphenyl (DODECA) has been carried out. Nonbonding interatomic distances of oxygen atoms inside of all the nitro groups are shorter than those corresponding to the intermolecular contact radii for oxygen. By means of the DFT B3LYP/6‐31(d, p) method a difference of 136 kJ mol⁻¹ between the X‐ray and DFT structures of DODECA was found. The bearer of the highest initiation reactivity in its molecule in solid phase should be the nitro group at 4′′′‐position, in contrast to those at 2′‐ or 2″‐positions in its isolated molecule. The most reactive nitro group in the DODECA molecule can be well specified by the relationship between net charges on nitro groups and charges on their nitrogen atoms, both of them for the X‐ray structure. The ¹⁵N chemical shift, corresponding to this nitro group for the initiation by impact and shock, correlates very well with these shifts of the reaction centers of the other six “genuine” polynitro arenes.     

露天矿中深孔微差控制爆破技术的试验与生产应用

结合自己多年来广州市珠江水泥厂石灰石露天矿中深孔微差控制爆破技术的试验与生产应用，通过计算机模拟爆破试验，进行起爆网络设计，爆破过程控制，爆破方向控制，岩石移动方向，块度大小控制，爆破振动，根底，硬墙的状况，爆堆的松散性、形状，后冲，实现“逐孔起爆”技术，改善爆破效果。并对过去的生产爆破参数和爆破方案加以修正，掌握了露天矿山爆破关键技术，优化露天矿山爆破参数，实现最小的投入，赢取最大的收益，降低矿山综合成本，充分合理的利用国家矿山资源。     

Study on the effects of geometry on the initiation characteristics of the oblique detonation wave for hydrogen-air mixture

The Oblique Detonation Wave Engine (ODWE) may act as a hypersonic propulsion system operating at high Mach numbers, which is an important member in the family of Scramjet. Hydrogen is a promising fuel for Scramjet, which provides wider Mach number range and is environmentally friendly. The geometry of the engine greatly affects the performance of the ODWE using hydrogen fuel. This investigation focuses on a novel wedge proposed recently, which may be utilized in scramjet engines. The wedge consists of two sub-wedges and a step. This research focuses on how the geometry of the wedge affects the initiation characteristics of the oblique detonation. Simulations are conducted on basis of Euler equations and a 9-species and 19-reactions mechanism. It is found that a larger leading wedge angle leads to a shorter initiation length. A larger step angle induces a longer initiation length. Few effects are observed on the initiation characteristics for the current range of depth. The streamline surface at the rear of the step weakens the rear shock wave and induces a longer initiation length. The streamline surface at the tip of the step begins to take effect when the initiation position is away from the step. This research provides basis for understanding the performance of the oblique detonation wave under different geometries and provides theoretical basis for scramjet engine design.     

瞬时聚合丙烯酸酯浆料的性能研究

探讨在采用瞬时聚合法直接合成固体丙烯酸酯浆料的过程中,疏水性单体丙烯酸丁酯用量对所生成丙烯酸酯浆料性能的影响.测试了不同丙烯酸丁酯用量下反应生成物的水溶性、水溶液黏度及对涤棉粗纱黏附性,并对合成的固体丙烯酸浆料进行红外表征.结果表明:在丙烯酸的中和度为50%、氧化还原引发体系中引发剂为单体量的6%时,丙烯酸丁酯为单体量的25%时合成的浆料性能最好,所生产的浆料为丙烯酸-丙烯酸钠盐-丙烯酸丁酯共聚物.     

46700m~2楼房一次爆破拆除

东北汽配城为框架结构,总建筑面积46700m2,周边环境非常复杂。该建筑物共有260根柱子,断面尺寸不尽相同。按建筑伸缩缝将楼房分为5个部分,分别采用了原地坍塌、定向倾倒、折叠倾倒一次控制爆破技术,并将土石方爆破的斜线起爆技术用于拆除爆破。由于爆破设计、施工及安全措施得当,爆破获得圆满成功。     

逐孔起爆技术在太和铁矿的应用

论述了逐孔起爆技术的原理和特点,以及其在太和铁矿爆破开采中的应用。采用这种方法有效地降低了矿石的大块率和选矿的破碎处理量,提高了铲装效率,保证了岩石爆破破碎的质量,降低了炸药单耗,对类似工程有很好的借鉴作用。     

控制爆破技术在改善露天矿边坡稳定性的应用

为防止露天矿边坡过爆和减小爆破振动对边坡的破坏,对边坡处炸药单耗、起爆方式、延时等因素,结合爆破反馈的数据进行了分析,提出了对生产爆破、缓冲爆破和预裂爆破各参数具有操作性的建议。     

桃林铅锌矿挤压爆破试验研究

针对桃林铅锌矿大爆破中的事故隐患问题,开展了挤压爆破研究,确定了适应该矿矿岩条件的挤压爆破参数,并将其应用于工业试验。试验表明,该爆破方法具有工艺简单、作业安全、操作方便,大块率低等优点。试验取得了良好的效果。     

应用决策集选播模式的SIP测控网络负载均衡策略

针对目前单优化目标选播模式容易导致负载发生新的不均衡问题,建立了SIP测控网络平台并分析其选播机理。采用网络层选播和应用层选播综合的方式,提出了最优决策集选播的负载均衡策略。选播目标为一个集合,包含多个满足要求的服务器,以避免蜂拥抢占服务器资源的情况发生;建立SIP测控网络最优决策集选播数学模型,采用证据理论决策选播目标权重,从而产生最优决策集。在OPNET仿真环境下,搭建SIP测控网络平台进行实验,结果表明最优决策集选播模式比单优化目标选播模式的服务器占用资源不均衡率降低了31%,能够很好地将负载均衡到各个服务器中,并减少了单个服务器处理多进程需要的额外资源开销。