碱洗塔洗塔系统的优化

介绍了氯乙烯合成工段碱洗塔洗塔工艺流程,并针对存在的问题对其进行了优化升级,使碱洗塔自控洗塔、配碱,提高了系统的自动化控制水平,节约了水资源,也降低了废水处理系统的负荷,最大限度地提高了碱液的利用率,提高了工作效率,增加了经济效益,     

个性营销能否撑起陶瓷企业那片天

前些天在杂志上看到过一个故事,说的是中国人和犹太人的区别,一个犹太人建了一所加油站,生意很好,第二个犹太人来了,就在加油站旁边建了一座购物中心,生意同样很好,第三个犹太人来了,就在旁边又建了一座游乐场,生意照样很好,第四个犹太人来了,就开了一家4S店,生意也是好的不得了,第五个犹太人来了,他建的是公共卫生间,也赚到了钱。可是在我国呢,第一个人建了一个加油站,赚钱了,第二个人看到了,觉得有利可图,也建了一个加油站,结果第三个,第四个,     

焦炉生产操作改进

介绍了焦炉生产中的改进措施,通过改进装煤方式,减少了装煤冒烟;配制新型填料,增强了炉体维护;改进了1M管的冲洗方式;改进炉顶水箱槽的高度;降低上升管底座的高度,杜绝连接处冒烟;改进装煤孔底座.通过采取这些改进措施,大大降低了生产成本,改善了职工的操作环境,降低了职工的劳动强度,提高了职工的工作效率,有效地保障了生产的平...     

石墨电极数控机床常见故障分析

近年来,各炭素企业为了扩大再生产和替换陈旧设备,相继加快了石墨电极机床数字化改造步伐,不仅降低了操作者的劳动强度,提高了生产效率,而且减少了人为误差,提高了控制精度,保证了加工质量.     

PUMP-200新型乳液泵组装机的研制与应用

介绍了PUMP-200新型乳液泵组装机的工作原理及特点,通过比较和分析,说明了该新机的运用,节省了大量的人力物力,降低了能耗,大大缩短了产品交货期,实现了产品质量的稳定,提高了生产效率,经济效益显著。     

带式过滤机在多品种氢氧化铝生产中的应用

介绍了带式真空过滤机的工作原理及其在多品种氢氧化铝生产方面的应用情况,并对带式真空过滤机使用过程中存在的问题进行了改造。改造之后,提高了洗涤过滤效率,降低了滤饼水分,降低了能耗,提高了产量,确保了产品质量,取得了较好的经济效益。     

高庄煤矿供热系统的改造

高庄煤矿针对原锅炉供热系统存在的问题进行了改造,拆除原锅炉,采用邻矿电厂的富余蒸气作热源,安装热交换器组。改造后保证了供热质量,节约了能源、资源,提高了矿区环境质量,降低了运行维护费用,节省了人力资源,减少了占地面积,节约了各项检查检测费用。     

绿色环保可降解乳化切削液的研制及工业应用

研制了绿色环保可降解的乳化切削液,确定了切削液的配方,对切削液的性能进行了测试,同时进行了工业应用,取得了较好的效果。     

焦炉生产操作改进

介绍了焦炉生产中的改进措施,通过改进装煤方式,减少了装煤冒烟;配制新型填料,增强了炉体维护;改进了1M管的冲洗方式;改进炉顶水箱槽的高度;降低上升管底座的高度,杜绝连接处冒烟;改进装煤孔底座。通过采取这些改进措施,大大降低了生产成本,改善了职工的操作环境,降低了职工的劳动强度,提高了职工的工作效率,有效地保障了生产的平稳顺行。     

医学专业物理化学教学改革的探索

结合多年的教学实践,分析了医学专业物理化学教学的现状和存在的主要问题,并对物理化学教学进行了改革和探索。改变了传统的教学模式,搭建了一个新的教学平台,增强了学生学习的主观能动性,提高了学生的学习效率和质量,培养了学生的创新意识和创新能力,取得了较好的教学效果。     

间苯二甲酸在瓶级聚酯生产中的作用及在线添加方式

瓶级聚酯切片生产中需要加入间苯二甲酸(IPA),简要介绍了IPA的添加对反应过程及产物性能的影响,以及在实际生产中,如何通过在线添加酯化物的方式控制一头两尾不同生产线上瓶级聚酯熔体中IPA的含量。     

Development of a pilot-plant process for the extraction of soy flakes with aqueous isopropyl alcohol

Soy flakes were extracted with aqueous isopropyl alcohol (IPA) at 77 C in a Kennedy countercurrent continuous extractor at a retention time of 71 min. IPA concentration was varied from 85.0 to 90.5% w/w and included the 87.7% IPA-water azeotrope. Solvent to meal ratios were varied from 1.5 to 3.0. The oil-IPA miscella leaving the extractor was chilled and coalesced to yield an oil phase and an IPA phase. The IPA phase was recycled to the extractor without being distilled. Excess IPA was expressed from the defatted flakes, and this also was recycled to the extractor. IPA recovered by distillation in the evaporator-stripper and desolventizer-toaster accounted for less than 10% of the total. Refined deodorized oils from the IPA extraction process compared favorably with their hexane counterpart in color, peroxide value and phosphorous and free fatty acid contents. Desolventized meals from the IPA process compared favorably with their hexane-extracted counterpart in protein, ash and fiber content.     

Silk fibroin nanofibers electrospun on glass fiber as a potential device for solid phase microextraction

The electrospinning technique was applied to coat fused silica fibers with regenerated silk fibroin (RSF) nanofibers, aiming to build a device applicable for solid phase microextraction analysis. The device was characterized by attenuated total reflectance infrared spectroscopy, thermal analyses (differential scanning calorimetry and thermogravimetric analysis), and scanning electron microscopy, and employed to extract/desorb isopropyl alcohol (IPA) from the headspace of an IPA aqueous solution. The electrospun coating proved to be thermally stable up to 250°C, even after 4 h of exposure to this temperature. A 2² factorial experimental design was used to evaluate the flow rate of the polymer solution and the distance between capillary tip and collector on the mean RSF fiber diameter. A low flow rate (0.20 mL h^?1) and large capillary tip‐to‐collector distance (12 cm) yielded fibers with mean diameter of (304 ± 46 nm). The nanofibers were heated to 250°C, simulating the conditions in the injector of a gas chromatograph (GC). In these conditions, the RSF nanofibers were found not to melt even after 4 h of exposure to heat, although slight structural damage was detected. Preliminary assays using the as‐constructed device built under optimized electrospinning conditions (0.20 mL h^?1 and 12 cm) were performed in a GC by contact with the headspace of a 50 ppm IPA solution to determine the extraction and desorption times. The results indicated that the extraction process stabilized after 20 min of contact with the headspace of the IPA solution. The desorption process was complete after 10 min at 140°C. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41717.     

Cleaning Efficiency of Amino‐Acid Surfactants with Polyoxyethylene Ether and Isopropanol in Liquid Carbon Dioxide

Although anionic surfactants have a distinct positive influence on the removal of particulate soil, the removal of particulate soils is insufficient in CO₂ compared to perchloroethylene. A series of amino‐acid surfactants was selected as main surfactants to study the influence of polyoxyethylene ether and cosolvent on the cleaning effect. Glu‐C12 and C16(3) gave the best cleaning results, which increased from a detergency value of 4.6 when no surfactants were used to 8.32 when surfactants were used. In all experiments, charged anionic surfactant particles were formed, which are responsible for the removal of particulate soil from fabric by electrostatic repulsion. The use of a cosolvent (Isopropanol [IPA]) had a positive effect on the removal of particulate soil when using Glu‐C12 and TX‐45. However, for other compounding combinations, the addition of IPA had a negative effect on particulate soil removal. Of the cosolvents investigated, IPA was the most suitable. With the polarity of the system increasing after adding IPA, the ethylene oxide groups of TX‐45 were partially extended to CO₂. Through the steric effects of branched methyl groups, the cleaning effect was improved.     

Effect of adsorption and solvent extraction process on the percentage of carotene extracted from crude palm oil

Palm carotene was successfully concentrated from crude palm oil (CPO) by a batch adsorption process using a synthetic (polymer) adsorbent followed by solvent extraction. Carotene was concentrated to about 20,000 ppm, or about 33.3 times the original concentration in CPO. Carotene recovery varied from 16 to 74% depending on the process conditions. Adsorption times, isopropanol (IPA) extraction times, temperatures of adsorption and solvent extraction process, effect of agitation during IPA extraction process, and adsorbent lifespan were evaluated to determine their effects on the percentage of carotene extracted and carotene concentration. The minimum adsorption time required was 0.5 h. However, an adsorption time of 1.5 h gave a significantly higher carotene concentration than adsorption times of 0.5, 1.0, and 0.2 h. The IPA extraction time was determined based on the final carotene concentration desired. The suitable temperature for adsorption and solvent extraction process was 40°C. There was no significant difference in the percentage of carotene extracted and carotene concentration between the IPA extraction process with and without agitation.     

Production of isophthalic acid from m-xylene oxidation under the catalysis of the H3PW12O40/carbon and cobalt catalytic system

Isophthalic acid (IPA) is commercially produced from m-xylene oxidation with the catalysis of the homogeneous Co–Mn–Br catalyst system. In this study, a catalytic system consisting of HPW/C and Co(II) has been put forward to oxidize m-xylene (MX) to IPA. The experimental results prove that the HPW/C and Co catalytic system is capable of catalyzing the oxidation of MX to IPA, which can obtain a higher MX conversion and IPA concentration than the homogeneous H₃PW₁₂O₄₀/Co(OAc)₂/Mn(OAc)₂ catalytic system. The heterogeneous catalytic system is also advantageous over the homogeneous catalytic system in the inhibition of the oxidation of acetic acid and IPA. The optimal amount of phosphotungstic acid supported on carbon is 7.5% (wt). The best dosage of HPW/C is 15 g l⁻¹. The optimum Co(II) concentration in the catalytic system for IPA production is 0.064% (wt). The best HPW/C activation temperature is 220 °C.     

瓶级PET切片的研究及分析

介绍了固相缩聚反应的工艺流程及瓶级PET切片的反应过程,从IPA和添加剂的用量,PET切片大小和形状,PET切片特性黏度,反应温度、结晶,氮气的影响等方面分析了固相缩聚的影响因素。     

瓶级聚酯质量对流变及加工性能的影响研究

研究和分析了加工温度、特性黏数、摩尔质量及其分布、间苯二甲酸含量(IPA)、二甘醇(DEG)含量等因素对瓶级聚酯流变性及加工性能的影响。结果表明,在低剪切速率下,温度的升高使熔体的切力变稀现象逐渐减弱,当剪切速率达到8 000 s-1以上时,温度及剪切速率都几乎对熔体的表观黏度没有影响;摩尔质量越高,熔体黏度的切变速率依赖性越大,摩尔质量分布宽有利于成型加工条件的控制;在相同剪切速率下,熔体的剪切黏度随着IPA含量的增大而逐渐降低;DEG含量低的聚合物熔体在低剪切速率下出现非牛顿性流动的现象比DEG含量高的要明显得多。     

Preparation of segmented, high molecular weight, aliphatic poly(ether-urea) copolymers in isopropanol. In-situ FTIR studies and polymer synthesis

The use of isopropanol (IPA) as the reaction solvent for the preparation of high molecular weight segmented polyether-urea copolymers based on cycloaliphatic diisocyanates was investigated. Reactivity of IPA with bis(4-isocyanatohexyl)methane (HMDI) and isophorone diisocyanate (IPDI) was studied between 0 and 40 °C using in-situ FTIR spectroscopy. HMDI, which has secondary isocyanate groups, shows a very slow reaction with a large excess of IPA at 0 and 23 °C. Analysis of the kinetic data indicates an activation energy of 51 kJ/mol for the reaction between HMDI and IPA. As expected, IPDI, which has both a primary and a secondary isocyanate (NCO) group, reacts faster with IPA compared with HMDI, which only has secondary NCO groups. However, the rate of reaction of IPDI with IPA at 0 °C is extremely slow (approximately 1% consumption of isocyanate in 60 min) thus allowing the use of IPA as the reaction solvent for polyether-urea synthesis. Preparation of high molecular weight, high-strength HMDI and IPDI based polyether-urea segmented copolymers in IPA has been demonstrated. Thermal analysis and stress-strain analyses were used to characterize the products.