非标压力机箱形主梁全约束优化设计

根据非标设备结构优化问题的特点,给出满足《钢结构设计规范》(GBJ17 88)规定的箱形主梁全约束优化设计方 法。将编制的内罚函数法优化程序应用于主梁的设计,计算结果表明,该优化方法可应用于实际设计。     

Influence of strain rate on interpass softening

Most laboratory simulations of hot rolling involve a scaling down of the strain rate from the much higher industrial levels. This leads to slower softening between each rolling pass, for which corrections must be made. In the present work, torsion testing simulations of “warm” rod rolling were conducted on a Ti-Nb interstitial-free (IF) steel at 840 °C and 770 °C(i.e., in the ferrite range). For this purpose, “strain rate corrected” interpass times were used, in addition to the more familiar corrections for the stress. The results are compared with those obtained from simulations using uncorrected industrial interpass times. At 840 °C, simulations using corrected interpass times led to high levels of softening between the stages of rolling, thus triggering the reinitiation of cycles of dynamic recrystallization. The initially high stress level at the start of these cycles was responsible for the large differences in the pass-to-pass mean flow stress behavior, compared with that observed when using uncorrected industrial interpass times, or continuous deformations. The differences were much less pronounced at 770 °C, where the rate of softening is much slower than at 840 °C. Predictions for softening based on the Avrami equation underestimated the softening observed using the continuous and uncorrected industrial interpass time schedules and overestimated it for the corrected ones. The former is due to the occurrence of recovery, which is not addressed by the Avrami relation, while the latter is due to the precipitation that takes place during the corrected (longer) interpass times. It was also found that simulations using continuous deformations are applicable only if the interpass softening that would be expected using the corrected interpass times does not exceed about 20 pct.     

钢坯修磨金属切除率数学模型的研究

从分析修磨过程运动学和单个磨粒切削入手,建立了磨削深度与磨削过程诸参数(如工艺、材料性能、砂轮性能等)的关系表达式,从而建立起金属切除率与各单项参数的定量关系,为改善或提高修磨效率和修磨过程控制提供了有意义的根据。理论分析与实验结果吻合良好。     

二叠氮季戊二醇二硝酸酯的研究

二叠氮季戊二醇二硝酸酯（ＰＤＡＤＮ）分子中有两种含能基─ＯＮＯ＿２和─Ｎ＿３，可望作为一种良好的炸药或火箭推进剂的组分。美国的Ｆｒａｎｋｅｌ等已合成出该化合物，并报道它在常温下（２２．５℃）是油状液体；但我们用相同方法合成出的产物却是熔点为３９．６～３９．７℃的晶体物质。本文介绍了我们的实验结果及其有关物理化学性质方面的数据。     

丙烯酸接枝聚丙烯纤维的结构与性能

本文研究了用化学引发剂引发丙烯酸接枝聚丙烯纤维的某些影响因素。红外光谱分析表明，丙烯酸接枝在聚丙烯大分子链的叔碳原子上。Ｘ－射线衍射和ＤＳＣ分析指出，纤维接枝后结晶度有所增加，接枝前纤维存在的β－变体转化成了α－变体，接枝纤维的吸湿性、离子交换容量和染色性随接枝率增加而增大。接枝纤维的力学性能有所下降。     

XD－YES：IC功能成品率模拟器的实现

首先建立缺陷空间分布和粒径分布的模型，并讨论了缺陷通过版图产生电路错误的过程，给出了ＩＣ功能成品率模拟器ＸＤ－ＹＥＳ的实现。用ＸＤ－ＹＥＳ对微电子测试图和实际ＩＣ的功能成品率模拟和分析表明，其结果与实际符合很好，从而表明ＸＤ－ＹＥＳ的可行性和实用性。     

固载杂多酸催化剂气相催化合成乙酸丁酯的研究

在气固相反应体系中研究了酸处理膨润士固载的具有 Keggin结构的四种杂多酸在乙酸丁酯合成中的催化性能。实验结果表明 :同一载体负载不同杂多酸催化活性相似 ;不同载体负载的同一种杂多酸的催化活性与催化剂的表面酸性呈顺变关系。同时考察了反应温度 ,空速 ,酸 /醇比对催化活性的影响。在酸 /醇比为 1 ,温度为 1 2 0℃ ,空速为 3～ 5h- 1时 ,正丁醇和乙酸有较高的转化率 ,选择性接近 1 0 0 %。     

基于Modbus协议的外输计量监控系统的设计与实现

原油的外输计量系统没有配套的上位机系统,其操作存在一定的缺陷。针对这种情况,在详细介绍了Modbus协议和CRC校验的基础上,提出了基于Visual Basic环境下与流量计算机通信的系统设计方案,在该设计中实现了基于Modbus协议的串口通信以及CRC校验。实际验证,该系统能够有效地解决原有问题。