Studies on Triple Base Gun Propellant Based on Two Energetic Azido Esters

Triple base propellant is the workhorse propellant because it possesses several advantages like reduced flash, flame temperature, and erosion of the barrel as compared to double and single base propellant. Hence, efforts are going on worldwide to increase its performance by increasing its energy using energetic plasticizers and binders. In the present article, nonenergetic plasticizer dibutyl phthalate (DBP) is replaced by two energetic azido ester plasticizers, tris(azido acetoxy methyl) propane (TAAMP) and bis(azido acetoxy) bis(azido methyl) propane (BABAMP), in triple base composition and their different properties are studied.

Experimental closed vessel (CV) results (loading density 0.2 g/cm³) clearly indicate that the triple base composition with 2% DBP has force constant 1018 J/g, which is increased to 1026 and 1030 J/g on replacement of DBP by 1 and 2% TAAMP, respectively. Mechanical properties of propellant compositions containing 1 and 2% TAAMP (compression strength 279 and 291 kg_f/cm², percentage compression 11.2 and 10.5, respectively) are also better than those of composition containing DBP (compression strength 275 kg_f/cm² and 10.3% compression). Similarly, 1 and 2% replacement of DBP by BABAMP shows further rise in energy (1032 J/g, 1038 J/g respectively) than that of compositions containing 1 and 2% TAAMP. These two compositions also exhibit better mechanical properties (compression strength 311.2 and 312.3 kg_f/cm², % compression 11.0 and 10.5, respectively) than compositions containing 1 and 2% TAAMP. The differential thermal analysis (DTA) results brought out the fact that the compositions containing energetic plasticizers revealed maximum decomposition temperature in the range of 172–174°C which is close to DBP plasticized triple base gun propellants (174°C). The energetic plasticized propellant compositions of both (TAAMP and BABAMP) showed sensitivity data in the range of (H₅₀ 19 to 22 cm, F of I 25 to 29 and friction insensitivity 19.2 kg) acceptable limit for gun propellant.     

DBP生产中副产废料的综合利用

采取实验方法，将DBP生产过程中产生的副产物丁醚进行提纯精制，过量的丁醇回收循环利用，取得良好的经济效益。     

Effects of tuber storage protein of yam (Dioscorea alata cv. Tainong No. 1) and its peptic hydrolyzates on spontaneously hypertensive rats

Yam storage protein (YSP) was purified from tubers of Dioscorea alata L. Tainong No. 1 (TN1) to homogeneity by DE‐52 ion‐exchange chromatography. The short‐term (24 h) and long‐term (25 days) antihypertensive effects of YSP‐TN1 and its peptic hydrolyzates (PH‐TN1) were measured in spontaneously hypertensive rats (SHRs). For 24‐h antihypertensive measurements, SHRs (age 10 weeks, body weight from 240 to 250 g) were administered orally once (YSP‐TN1 and PH‐TN1, 40 mg kg^?1 SHR) to measure the mean blood pressure (MBP), systolic blood pressure (SBP) and diastolic blood pressure (DBP). For a long‐term antihypertensive measurement, SHRs (age 12 weeks, body weight from 250 to 270 g) were administered orally once a day for 25 days (YSP‐TN1, 40 mg kg^?1 SHR) to measure SBP, DBP and MBP. Captopril (10 or 15 mg kg^?1 SHR) was used as a positive control. It was found that short‐term administration of 40 mg kg^?1 SHR of YSP‐TN1 and PH‐TN1 effectively lowered SHRs' MBP, SBP and DBP (For YSP‐TN1, the lowest blood pressure was reached in the fourth hour and for PH‐TN1 in the eighth hour). The lasting effects of PH‐TN1 on reduced SHRs' BP were better than those of YSP‐TN1 for one oral administration. For oral administration of 40 mg YSP‐TN1 kg^?1 SHR, the reduced MBP was 21.5 mmHg, which was comparable to 25.2 mmHg (the fourth hour) of 10 mg captopril kg^?1 SHR oral administration. For oral administration of 40 mg PH‐TN1 kg^?1 SHR, the reduced MBP was 33.7 mmHg, comparable to 38.4 mmHg (the fourth hour) of 15 mg captopril kg^?1 SHR. For long‐term 25‐day oral administration of 40 mg YSP‐TN1 kg^?1 SHR once a day, it was found that a feeding trial of YSP‐TN1 effectively lowered SHRs' SBP, DBP and MBP. The greatest reduction in SHRs' blood pressure was reached on the ninth day, for the reduced SBP, 27.7 mmHg; for the reduced DBP, 28.3 mmHg; and for the reduced MBP, 27.5 mmHg. Copyright © 2006 Society of Chemical Industry     

Pharmacokinetics of Dibutyl Phthalate (DBP) in the Rat Determined by UPLC-MS/MS

Dibutyl phthalate (DBP) is commonly used to increase the flexibility of plastics in industrial products. However, several plasticizers have been illegally used as clouding agents to increase dispersion of aqueous matrix in beverages. This study thus develops a rapid and validated analytical method by ultra-performance liquid chromatography with tandem mass spectrometry (UPLC-MS/MS) for the evaluation of pharmacokinetics of DBP in free moving rats. The UPLC-MS/MS system equipped with positive electrospray ionization (ESI) source in multiple reaction monitoring (MRM) mode was used to monitor m/z 279.25→148.93 transitions for DBP. The limit of quantification for DBP in rat plasma and feces was 0.05 μg/mL and 0.125 μg/g, respectively. The pharmacokinetic results demonstrate that DBP appeared to have a two-compartment model in the rats; the area under concentration versus time (AUC) was 57.8 ± 5.93 min μg/mL and the distribution and elimination half-life (t_1/2,α and t_1/2,β) were 5.77 ± 1.14 and 217 ± 131 min, respectively, after DBP administration (30 mg/kg, i.v.). About 0.18% of the administered dose was recovered from the feces within 48 h. The pharmacokinetic behavior demonstrated that DBP was quickly degraded within 2 h, suggesting a rapid metabolism low fecal cumulative excretion in the rat.     

短程蒸馏工艺参数对二元组分分离效果的影响

应用刮膜式短程蒸馏装置以邻苯二甲酸二甲酯(DMP)和邻苯二甲酸二丁酯(DBP)二元组分为对象进行系列实验。重点考察了进料速率、蒸馏温度、蒸馏压力和刮膜器转速对二元组分分离效果的影响。实验结果表明:在实验所取数值范围内,蒸馏温度和蒸馏压力为二元组分分离效果的主要控制因素,而进料速率和刮膜器转速对于分离效果的影响相对不明显。     

Effect of constructed wetlands receiving agricultural return flows on disinfection byproduct precursors

The effects of wetland treatment on disinfection byproduct precursors were evaluated for six constructed wetlands receiving agricultural return flows in the Central Valley of California. Wetlands varied in size, age, vegetation, hydrologic residence time (0.9-20 days) and water management (continuous flow vs. flood pulse). The effects of wetland treatment were determined by analyzing input and outflow waters for dissolved organic carbon concentration and quality, bromide concentration, and formation potentials for nine disinfection byproduct species, including trihalomethanes, haloacetronitriles, chloral hydrate, and haloketones. We hypothesized that hydraulic residence time was a key factor governing differences in disinfection byproduct precursors. Small wetlands (<3 ha) with short hydraulic residence times (<2 days) did not produce significant changes in disinfection byproduct precursor concentrations with respect to the agricultural return flows input to the wetlands. In these wetlands hydraulic residence times were not long enough to promote processes that adversely affect dissolved organic carbon and bromide quantity, such as evapoconcentration and leaching from vegetation. Thus, less negative effects were associated with disinfection byproduct formation. In contrast, larger wetlands (>100 ha) with long hydraulic residence times (>10 days) resulted in higher dissolved organic carbon and bromide levels, increasing disinfection byproduct formation by factors ranging between 1.7 and 10.2 compared to agricultural return flows. Results from this study provide important information for optimizing the design and management of constructed wetlands to effectively combine control of disinfection byproduct precursors with other water quality parameters.     

DBP装置脱醇系统的优化设计

通过对 DBP装置脱醇系统的分析及模拟计算 ,提出了扩产改造方案 ,消除了原脱醇系统存在的问题 ,提高了产品质量 ,系统能力增加一倍 ,达到了改造目的     

杂质对化成过程影响的初步研究

讨论聚合物锂离子电池在化成时出现充电异常的主要影响因素。通过实验表明:在生产中残留在电池中的DBP、CH3OH、H2O是造成电池化成过程充电异常的主要杂质并可能影响SEI层的性质。     

CB-TiO2薄膜光催化臭氧氧化邻苯二甲酸二丁酯研究

研究了碳黑改性TiO2（CB—TiO2）薄膜催化剂光催化臭氧氧化典型有机污染物邻苯二甲酸二丁酯的过程，重点研究了臭氧投加量对邻苯二甲酸二丁酯浓度降解和总有机碳（TOC）去除率的影响。结果表明，邻苯二甲酸二丁酯的光催化臭氧化（TiO2／UV／O3）过程的TOC去除率比光催化氧化（TiO2／UV）、单独臭氧化（O3）和光助臭氧化（UV／O3）过程明显增高。动力学研究表明，邻苯二甲酸二丁酯完全矿化过程遵循零级反应，仅取决于臭氧浓度而与邻苯二甲酸二丁酯浓度无关；邻苯二甲酸二丁酯在TiO2／UV／O3作用下完全矿化的速率常数是UV／O3过程的1．2～1．76倍（同样臭氧浓度下），是TiO2／UV过程的2．24～3．54倍。     

基于动态BP网络的实验电炉温度控制系统

针对一类不允许出现超调的工艺参数，提出了采用动态BP网络对工艺参数进行控制，可以达到良好的效果。并以实验电炉为对象，用工控机对其炉温进行控制，结果表明，采用动态BP网络进行控制，可以无超调地无限逼近给定值，控制精度高，控制时间较短。因此可以认为，用动态BP网络对这一类工艺参数的控制是有效的。