Preparation and characterization of conducting polymer coating on ABS substrate

Conducting polymer coatings on ABS were prepared by dipping them into m‐cresol solutions containing polyaniline (PANI), poly(o‐toluidine) (POT), and poly(o‐anisidine) (PoAN) protonated with dioctyl hydrogen phosphate (DiOHP) in the presence and absence of polystyrene (PS). The surface resistivity of ABS plates coated with DiOHP‐doped PANI in the presence and absence of PS were 5.3 × 10⁷ and 3.0 × 10⁵ Ω, respectively. The ABS plates coated with DiOHP‐doped PoAN and ‐doped POT showed higher resistivities (4.2 × 10⁹ and 2.4 × 10⁷ Ω, respectively) than that with DiOHP‐doped PANI. Although the conductivity of the coated ABS with DiOHP‐doped PANI was less in the presence of PS, the permanency and uniformity of the coating, which are very important for practical use, were much improved. Coatings and the coated ABS were characterized by X‐ray diffraction, TG/MS, SEM, and reduced viscosity measurements. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 81: 2661–2669, 2001     

Effect of ammonia on the thermal decomposition of ammonium nitrate

The effect of the partial pressure of gaseous ammonia on differential thermal analysis and thermogravimetric curves of ammonium nitrate has been determined. Observed variations of the thermal effect and decomposition rate constitute a basis for considering the factors which determine the decomposition and equilibrium of exo- and endothermic processes.     

造粒硝铵装置改产硝酸铵钙

介绍硝酸铵钙的物化性能，采用硝酸铵与石灰石混和法生产硝酸铵钙的工艺流程，以及技术经济指标，硝酸铵钙用作肥料能增加养分种类，改善土壤品质，并具有适应性广等特点。是硝铵生产厂家一条很好的改产途径。     

Investigation of factors affecting caking tendency of calcium ammonium nitrate fertilizer and coating experiments

Caking of fertilizers is an important problem both to manufacturers and users. Manufacturers must recycle the caked fertilizer to the process resulting in an extra cost and users may have difficulties during the application of the fertilizer to the soil. In the first part of this study major factors which influence caking of a commercial grade calcium ammonium nitrate (CAN) fertilizer were investigated with a laboratory caking apparatus kept in a controlled atmosphere. It was observed that the caking tendency of CAN fertilizer increases almost linearly with pressure exerted on the fertilizer and with moisture content of the fertilizer at a temperature of 35 °C. The results indicate that the phase transition of ammonium nitrate between crystalline forms IV and III plays a significant role in caking of CAN since caking tendency is greatly reduced below the phase transition temperature which occurs at about 32 °C. In the second part of the study, the effectiveness of some coating materials to reduce the caking tendency of CAN fertilizer were tested. Among the materials tested, kieselguhr gave the most satisfactory result under the experimental conditions employed.     

硝酸铵产品的改性研究

为了适应硝酸铵市场的需求,云天化公司对硝酸铵进行了改性研究。通过在现有装置上进行的四硝酸锌工业试验、硝酸铵钙工业试验和硝基复合肥的工业试验研究表明,硝酸铵钙和硝基复合肥的生产都存在许多问题,需要改进现有工艺和增加许多设备。而自行开发的硝酸锌熔融生产工艺在不改变现有装置情况下,生产的硝酸锌总氮为33.04%、NH4NO3为34.4%、抗压强度为9.92 N,产品的粒度、水分、强度都达到了国家标准,其松散度较好。     

粒度对硝铵类炸药静电火花感度的影响

采用喷射细化法和滴加法分别制备了3种粒度的RDX、HMX、PETN粉末。采用激光粒度分析仪和扫描电子显微镜（SEM）对样品进行了表征,并对其进行了静电火花感度实验。结果表明,随着粒度的减小,RDX、HMX、PETN 3种样品的静电火花感度均逐渐升高。从理论上分析了硝铵类炸药粒度对其静电火花感度的影响。     

硝酸铵的热稳定性研究

分析了硝酸铵热分解的机理及影响因素,介绍了测定硝酸铵热稳定性的方法及其优缺点。结果发现,加速度量热仪和C80微热量热法是目前最安全、简便、实用的反应性化学物质热危险性的评价方法。研究结论为解决硝酸铵生产、储存和运输过程中的安全问题提供了重要参考。     

Thermal decomposition of ammonium nitrate

The thermal decomposition reactions of ammonium nitrate (AN) are reviewed. Both neat AN and AN containing various contaminants are examined, however quantitative kinetics results are not encompassed. Also not included is the performance of AN as the oxidizer in rocket propellants or in explosives such as ANFO. The review is intended to be the most comprehensive review of decomposition reactions of AN since Berthelot's treatise of 1892. Despite hundreds of papers on the topic that have appeared in the intervening years, understanding of decomposition mechanisms remains only modestly more complete than it was in Berthelot's day. However, some additional reaction steps and mechanisms have been identified and these are discussed. Explosions of AN most commonly involve fire as the proximate cause, yet chemical-mechanism research on the topic is nil. A modest number of studies have explored the potentiation of AN decomposition by organic contaminants. These have, thus far, not produced guidance useful for promoting of safety from fire-related causes. Contamination from inorganic sources, notably chlorides is better understood and some mechanisms have been studied. The UN classification of AN as an oxidizer, instead of as an explosive, should not be interpreted literally, since AN has been associated with numerous detonation disasters.     

预处理对钼基片镀钌层结合力的影响

常用的钼基片镀钌前预处理工艺包括碱洗除油、阳极浸蚀、酸洗、活化、预镀冲击镍.讨论了预处理工艺中碱洗工艺方案、阳极浸蚀的电流密度和时间,以及预镀冲击镍的电流波形对钌镀层结合力的影响.在65℃的50 g/L氢氧化钠溶液中以阳极电流密度16 A/dm<'2>处理2 min,在体积分数为200 mL/L的硫酸溶液中以阳极电流密...     

农用硝酸铵的改性方法

介绍国内和国外硝酸铵改性的现状,并提出硝酸铵改性的发展方向。     

Detonation properties of ammonium nitrate

A published equation for determining the detonation parameters of mixed explosive compositions is used to compute the detonation characteristics. When this equation was used to analyze the detonation parameters of 6ZhV ammonite, the detonation characteristics of the TNT and ammonite in this composition were taken from published data and the parameters of the ammonium nitrate were determined from the equation for the mixture. The results of large-scale experiments on a mixture of no more than 3% TNT with ammonium nitrate are presented. The detonation velocity of ammonium nitrate is found to be 5 km/sec. The equation for the mixture is used to determine the pressure and adiabatic exponent of the explosion products of ammonium nitrate when the size of the explosion exceeds the limiting diameter. Translated fromFizika Goreniya i Vzryva, Vol. 35, No. 2, pp. 102–104, March–April 1999     

硝酸铵制冷剂的研究

对以硝酸铵为化学制冷剂的研究结果表明,硝酸铵作为固/固式冷袋中的冷却剂时,其冷却效果(冷却温度和冷却时间)与硝酸铵、十水碳酸钠的配比有关。经过适当热处理后的十水碳酸钠具有较好的致冷效果。     

硝酸铈铵复盐制备工艺研究

对硝酸铈铵复盐的制备工艺进行了研究。分析了反应物的加入量、反应温度、反应时间以及其它工艺条件对制备硝酸铈铵复盐产品质量的影响。得出了制备分析纯硝酸铈铵复盐的方法。该方法可获得纯度达99%以上的橘红色硝酸铈铵复盐,收率达85%以上。     

硝酸铵生产过程安全技术分析

简要介绍了硝酸铵的各种物理、化学性质以及我国工业上常采用的硝酸铵生产的工艺流程.在此基础上,结合具体生产实际,对生产过程中可能发生的硝酸铵均相分解爆炸的各种影响因素(温度、杂质、物料积聚、热敏感度),以及可能发生危险的其他因素(开、停车,传爆等)进行了详细的安全技术分析,并提出了相应的预防对策.     

Melting of hydrogels containing ammonium nitrate

The fusion of hydrogels containing ammonium nitrate (AN) has been investigated by differential scanning calorimetry (DSC). The polymers used were guar and xanthan gums as well as synthetic polyacrylamide polymers. Water in hydrogels could be classified into three types labeled as ordinary water (hump of the melting peak), intermediate water (broad component of the peak), and bound nonfreezing water (without any phase transition). The temperature of fusion of intermediate water was about 10° to 35°C lower than that of ordinary water. Intermediate and bound water was found in all the gels studied, whereas ordinary water existed mainly in mixtures with total water content higher than 62%. The presence, type, and concentration of a crosslinker had no effect on the amount of bound water in hydrogels containing AN. In such mixtures the amount of nonfreezing water increased with the polymer concentration as well with the AN proportion relative to water and represented in some cases up to 27% of the gel. Cold-crystallization was observed in all cases (except xanthan) and was probably initiated by AN or the crosslinking agent.     

硝酸铵的结块与防止

硝酸铵的吸湿性、多晶性造成了硝酸铵的结块。分析了影响松散型硝酸铵松散度降低并结块的主要原因是水分、造粒颗粒度、温度、松散添加剂、添加剂添加量、包装方式和储存条件,提出了提高硝酸铵松散度的具体改进措施。对防止硝酸铵结块的几种途径进行了讨论,介绍了防结块剂的应用情况,并介绍了五种硝酸铵专用防结块剂的特点及其应用情况。     

扩散退火温度对钢表面铁–铝金属化合物镀层的影响

通过热浸铝和扩散退火处理在45钢表面制备Fe–Al金属间化合物镀层。研究了镀层微观形貌、物相和显微硬度随退火温度升高的变化规律。结果表明,经700°C扩散退火处理的热浸镀铝钢,镀层与基体之间呈长舌状结合。800°C退火处理后,长舌状形貌基本消失,镀层厚度增至300μm。900~1 000°C退火处理后,镀层呈连续的双层结构,与钢基体结合得更紧密。随扩散退火温度升高,镀层由富铝相Fe2Al5转变为富铁相Fe Al和Fe3Al,导致镀层显微硬度降低。     

Anomalies in the burning of ammonium perchlorate and ammonium nitrate

Conclusions We have considered possible mechanisms of retardation of the chemical reactions when ammonium nitrate and perchlorate burn and have shown that one such mechanism is retardation by the water formed during combustion.We have studied the effect of the additives silica, liquid silicone, calcium stearate, etc. on the burning of ammonium perchlorate and ammonium nitrate catalyzed with chromium oxide in order to establish the causes of the anomalies observed during their combustion.We have shown that over a certain pressure range adding silica eliminates the observed anomalies (fall in burning rate with increase in pressure and pulsating combustion), whereas the addition of calcium stearate intensifies them.Depending on the pressure interval and the conditions under which combustion proceeds, the same additive may play the role of an inert admixture, a catalyst, or an inhibitor, which is apparently associated with changes in the leading reactions in differentpressure intervals.The author warmly thanks V. K. Bobolev for his assistance.Fizika Goreniya i Vzryva, Vol. 4, No. 3, pp. 314–322, 1968     

Antibacterial effect of nanometer-size grafted layer of quaternary ammonium polymer on poly(ether ether ketone) substrate

Owing to its excellent physicochemical properties, poly(ether ether ketone) (PEEK) has been used clinically for medical implants. However, its surface properties should be improved to further enhance its compatibility with a living organism and infection resistance. Here, we examined the surface construction via a combined process, that is, the self-initiated photoinduced graft polymerization of N,N-dimethylaminoethyl methacrylate (DMA) on PEEK substrate followed by polymer quaternization using various bromoalkanes (Q-PDMA-g-PEEK). Using a Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy, the grafting and quaternarization of poly(DMA) (PDMA) on the PEEK substrate was confirmed. The degree of quaternizations was at least 60% even when the various bromoalkanes were reacted. The Q-PDMA-g-PEEK with 1-bromooctane (BrC₈) (C₈-Q-PDMA-g-PEEK) substrate exhibited the highest ζ-potential of other Q-PDMA-g-PEEK substrates. However, no significant differences were observed in the degree of quaternization, thickness of the polymer layer, and hydrophilicity of all modified PEEK substrates. In addition, from antibacterial test with Escherichia coli, the C₈Q-PDMA-g-PEEK substrate exhibited the highest antibacterial rate (80%) among Q-PDMA-g-PEEK substrates examined. Therefore, we concluded that the surface ζ-potential is the one an important parameter for manufacturing PEEK substrates with bactericidal properties.