无卤阻燃剂对聚乙烯复合材料性能影响的研究

采用聚磷酸铵(APP)与季戊四醇(PER)协效无卤阻燃聚乙烯(PE)复合材料,制备出不同膨胀阻燃剂用量的无卤阻燃PE复合材料,研究阻燃剂的添加量对材料性能的影响,并观察阻燃剂在复合材料中的分散状况。结果表明,随着增加体系中膨胀阻燃剂的添加量,材料拉伸性能与抗冲击性能变差,阻燃性能得到明显提高,阻燃剂的分散效果变差,团聚现象加重。     

氯离子对硫铵结晶系统的影响及对策

研究了硫铵结晶系统中氯离子的来源以及对硫铵结晶系统的影响,并制定了控制氯离子含量的对策。硫铵结晶系统由于氯离子进出严重不平衡,导致母液中的氯离子含量高,造成设备腐蚀,影响产品质量和系统安全,因而必须控制氯离子的含量。     

吸水膨胀弹性体PVA-g-PBA的研究

在水介质中.在氮气保护下以硝酸铈铵(CAN)为引发剂,将丙烯酸丁酯(BA)接枝到聚乙烯醇(PVA)上,制得水膨胀弹性体PVA—g—PBA。通过红外光谱证实了接枝物的形成。讨论了PVA浓度、单体浓度、引发剂浓度和反应温度对接枝物接枝率(G％)的影响。结果表明随PVC浓度增大,接技率降低.[PVA2.5×10-4mol/L.[BA]0.702mol/l、[CAN]0.01mol/L45℃接枝率较高.接枝率越高其吸水膨胀率越低,8h达吸水平衡,最大吸水率为165.1％。     

Zn~(2+)和HCO_3~-对纳米磁性铁去除水中砷的影响

研究Zn2+和HCO3?对纳米磁性铁去除水中砷的影响。结果表明:Zn2+可以显著增强纳米磁性铁对砷的吸附,使As(Ⅴ)去除率由原来的66%提高到99%以上;HCO3?对纳米磁性铁吸附砷具有明显的抑制作用,使As(Ⅴ)去除率降至15%;而Zn2+可以削弱HCO3?对As(Ⅴ)吸附的抑制效应,在较短时间内(2 h)去除90%以上的As(Ⅴ),达到世界卫生组织规定的饮用水砷标准10μg/L。     

5%碳酸氢钠严格控制代谢性酸中毒对活体肾移植患者术后早期肾功能的影响

目的：观察使用5%碳酸氢钠严格控制代谢性酸中毒是否可改善活体肾移植患者术后早期肾功能。方法：选择2019年3月至2020年3月于中国科学技术大学附属第一医院择期行活体肾移植手术的120例尿毒症患者为研究对象,随机分为观察组和对照组。观察组术中根据碱剩余（BE）测量值补充5%碳酸氢钠,维持－3 mmol/L≤BE≤+3 mmol/L。对照组仅在明显代谢性酸中毒（BE≤－10 mmol/L或pH≤7.25）时才补充5%碳酸氢钠。调整分钟通气量,使PaCO2在正常范围内。记录患者麻醉前（T0）、麻醉诱导后10 min（T1）、肾动脉血流开放前（T2）、肾动脉血流开放后5 min（T3）、手术结束时（T4）的血流动力学指标及术中出血量、输液量、手术时间。记录术后1、2、3、7、30 d的肌酐、尿素氮及尿量。结果：与对照组相比,观察组术中5%碳酸氢钠输注量明显增加,去氧肾上腺素使用量明显减少（P<0.05）,对照组无输注5%碳酸氢钠指征;观察组术毕时pH、BE明显大于对照组（P<0.05）。与T0时比较,T3时两组MAP、CVP均明显降低（P<0.05）。观察组术后1、2、3、7 d血肌酐、尿素氮含量明显低于对照组（P<0.05）。观察组术后1、2、3 d尿量明显多于对照组（P<0.05）。结论：活体肾移植术中应用5%碳酸氢钠严格控制代谢性酸中毒可改善术后早期肾功能。     

RE^3＋—NH4^＋—CO3^2—体系的研究

以碳酸氢铵为沉淀剂，制得片状的碳酸镧晶体和由微晶聚集而成的球状碳酸钇晶体，经鉴定它们分别属于正交与三斜晶系。同时制备了复盐ＮＨ４Ｌａ（ＣＯ３）２·１６Ｈ２Ｏ及ＮＨ４Ｙ（ＣＯ３）２·０８Ｈ２Ｏ的晶型沉淀。     

甲醛／氟化铵／有机羧酸盐酸化液的性能研究与现场试验

针对胜利纯梁油田泥质含量高的地质特点，研制了以甲醛、氟化铵和有机羧酸为主要成分的ＦＡＣ酸化液。本文介绍了ＦＡＣ酸化液的酸化机理、性能及现场试验情况。结果表明，该酸液腐蚀性小，与地层的反应速度低，不易产生二次沉淀，适合于低渗透砂岩油层的深部酸化     

A technical method to improve NOx/NH3 mixing ratio in SCR system and its engineering applications

A technical method for diagnosing the distribution of NO_x flux within the cross-section area in front of ammonia injection grid (AIG) was proposed for guiding the valve-tuning of AIG branch-pipes, in order to optimize the NO_x/NH₃ mixing ratio in the selective catalytic reduction (SCR) system of power plant. The weight coefficient of each branch-pipe in AIG system can be quantitatively determined with regard to the distribution of NO_x flux in the corresponding sub-zone of the cross-section area. The control strategy of the valves for different AIG branch-pipes can be achieved for guiding the NH₃ injection and improving the NO_x/NH₃ mixing ratio within the whole cross-section area in front of AIG. The technology has been applied on one side of the SCR system flue-gas tunnels (normally two tunnels for the SCR system called as A-side and B-side) of a 660 MW plant for more than one year. The ammonia consumption rate of the SCR system was reduced about 12.62% and the uniformity of outlet NO_x distribution was estimated to be greatly improved by about 79.01% with regard to the standard deviation. The rising rate of the flue gas resistance of the air preheater was slown down by 39.18% compared to that of the other flue-gas tunnel of SCR system. This implied that the formation of the sticky ammonium bisulfate (ABS) on air preheater was significantly inhibited through the application of this technology.     

Taguchi Optimization of Solvent-Antisolvent Crystallization to Prepare Ammonium Perchlorate Particles

The sphericity and size of ammonium perchlorate (AP) particles significantly influence the properties of composite propellants. As the AP particles become more spherical, the accumulation coefficient increases, the viscosity during casting decreases, and the particle loading and burning rate increase. Hence, the production of micronized AP particles with an average size between 1 and 20 μm is important to increase the loading percentage of AP in the composite propellant. Here, the Taguchi experimental design was used to optimize the solvent-antisolvent crystallization (SAC) process for the preparation of micronized AP particles with higher sphericity. SAC parameters such as the type of antisolvent, the solvent-to-antisolvent ratio, the antisolvent temperature, the stirring speed, and the retention time were investigated at four levels. The type of antisolvent and the solvent-to-antisolvent ratio were found to mainly contribute to improving the sphericity and size of the AP particles, respectively.     

硫酸体系中锰钽铌矿加压浸出研究

针对单一硫酸体系锰钽铌矿加压浸出下钽铌浸出率均不到10%的问题,在硫酸体系引入助浸剂,考察氟化铵、双氧水、反应压强、硫酸浓度、反应温度、氟化铵矿比对锰钽铌矿加压浸出的影响,采用XRD对浸渣进行物相表征。实验结果表明,在锰钽铌矿加压浸出中,引入助浸剂氟化铵,温度200℃、硫酸浓度50%及氟化铵/矿比为0.8∶1的条件下钽浸出率超过93%,铌浸出率超过96%。引入氟化铵对硫酸体系下锰钽铌矿的加压浸出效果的提升十分显著。