PBX传爆药制造中的界面化学问题

利用界面化学原理分析了PBX型传爆药配方中高分子粘结剂与炸药晶体粘结力的来源,讨论了溶液混合蒸馏工艺和水悬浮工艺中的润湿模型;根据动力学原理分析了工艺条件对包覆效果的影响,并指出目前存在的问题和今后的发展方向。     

大型捆绑助推器气动干扰流场数值模拟

从三维薄层近似N-S方程出发,采用TVD差分格式,对某捆绑了2个大型助推器的运载器(RLV)流场进行了计算,得到了大型捆绑助推器真实复杂流场.数值结果表明在捆绑大型助推器后,在运载器头部附近产生了很强的弓形激波;数值结果也较好地反映了助推器的喷流与运载器芯级发动机的喷流相互干扰状况,为今后大型捆绑式可重复使用运载器的气动设计提供了理论依据和计算方法.     

环锥形传爆药的多点同步起爆网络的设计

提出了将多点同步起爆网络用于起爆新型传爆药装药结构,以提高传爆药起爆能力的方法;研究了“一入四出”、“一入八出”同步起爆网络的设计方法,并分析了其同步时间表达式及同步时间的影响因素。分析表明：网络的机械加工精度、装药密度的一致性和爆轰波拐角偏差是主要影响因素。     

传爆药起爆效果的影响因素研究

采用侧向钢凹法考察传爆药柱的起爆效果，通过改变聚奥－X传爆药柱的药量，得出了在一定条件下聚奥－X最佳起爆效果的药量。初步讨论了传爆药技的形状对起爆效果的影响。     

Assuring pulsation-free flow in a directly pressurized fuel delivery at a retail hydrogen station

When a retail hydrogen station operates using booster compressors to directly fill cars, a need for an additional high-pressure buffer volume is present, in order to mitigate potential pressure pulsations in the system. In the case of the Cal State LA Hydrogen Fueling Station, pulsations with a magnitude up to 6.7 MPa were observed with no buffer volume during 70 MPa fueling. Thus the focus was placed on determining the minimum buffer volume required to ensure pulsation free operation to the entire downstream system (booster compressors, piping and the vehicle hydrogen hardware). A mathematical model of volumes involved has been developed and compared to experimental measurements. The station configuration allows isolating one or more of the four high-pressure buffer tanks with which the station was upgraded to reduce pulsations. Each tank has a volume of 0.05 m³. A relatively simple model developed shows a strong correlation with the experiments in determining the maximum pulse and the minimum additional high-pressure buffer volume. Effectively, one buffer tank would have provided a proper operation of the station by keeping the pressure pulsation magnitude under 0.2 MPa.     

Factors influencing the use of booster seats: a state-wide survey of parents

This study used telephone interview data on booster seat use from a state-wide probability sample of parents with children ages 4-8-years-old who were living in Michigan. Interviews were completed with parents of children in 350 households. Analyses examined the entire sample, and three sub-groups: always users, part-time booster seat users, and booster seat non-users. Results indicated that booster seat legislation was a key determinant of the level of use and the motivation to use booster seats. Nearly 70% of part-time users said that they used booster seats because they believed it was the law. Similarly, 60% of part-time and non-booster seat users said that they would be more likely to use booster seats if use were mandated by law, with non-users being 3.5 times more likely than part-time users to agree that a law would increase their booster seat use. Finally, over 90% of part-time and non-booster seat users said it would be easier for them to use booster seats if a law required it, and non-users were almost six times more likely than part-time users to agree that a law would make use easier. The need for booster seat laws, issues of social equity, and implications for intervention were discussed.     

Preparation and Performances of Castable HTPB/CL‐20 Booster Explosives

HTPB/CL‐20 castable booster explosives were prepared successfully by a cast‐cured process. Scanning electron microscope (SEM) and the charge density test were employed to characterize the molding effect of HTPB/CL‐20 explosives. The propagation reliability, detonation velocity, mechanical sensitivity, thermal decomposition characteristics and thermal stability of the HTPB/CL‐20 explosives were also measured and analyzed. The results show that, when CL‐20 content is less than 91 wt.‐%, the charges with better molding effect were obtained easily. The critical diameter of HTPB/CL‐20 explosives is less than 1 mm, which exhibits good propagation reliability. When the density of HTPB/CL‐20 charge with 91 wt.‐% CL‐20 is 1.73 g cm⁻³, its detonation velocity can reach 8273 m s⁻¹. Moreover, this kind of explosives has low mechanical sensitivity and good thermal stability.     

陶瓷抛磨废料免烧砖的制备与强度研究

陶瓷抛光砖的产量已位居我国瓷砖产量第一位,其生产的陶瓷抛磨废料已严重污染环境。笔者使用陶瓷抛磨废料替代部分石粉和砂制备免烧砌墙砖,研究结果发现:在未添加激发剂时,陶瓷废料的加入降低了砖坯强度;当加入1%自制激发剂后,与陶瓷废料活性成分生成硅酸钙(CSH)和钙矾石(AFt),可使砖坯强度提高2~3倍,并可明显降低生产成本,最大降幅可达26.8%。     

真空助力器主缸总成通用模拟负载结构设计

设计了一种适于各种型号的真空助力器及制动主缸总成抽检的通用模拟负载。首先对助力器主缸总成及检测项目进行了分析,确定通用负载由常规负载和ABS负载两部分组成,接着对通用的常规负载和ABS负载(弹簧负载)进行了设计,最后通过对特定产品的测试,对负载的性能进行了验证。测试结果表明,该负载能满足真空助力器及制动主缸总成多项性能测试和常规耐久测试,同时又能满足ABS耐久测试要求。该负载为真空助力器及制动主缸总成的出厂前检测提供支持。     

H型钢万能轧机液压动态轴向调整

简介H-Beam万能型钢轧机动态轴向调整控制系统的结构、原理及实现方法,以及动态轴向位置偏差单元、增压缸的结构及其对中控制、夹持板/增压缸动态位置基准值确定等。