聚天冬氨酸的结构及其阻垢性能研究

对由马来酸酐胺化热聚合(方法Ⅰ)和由L-天冬氨酸单体热缩聚法(方法Ⅱ)合成的聚天冬氨酸(PASP)利用凝胶渗透色谱和红外光谱对产物进行了分析比较,认为工艺路线和反应条件的改变影响了产物的平均相对分子质量和相对分子质量的分布。产物的静态阻垢试验结果表明,方法Ⅰ所得产物在重均相对分子质量(Mw)为3000左右时的阻垢率和方法Ⅱ所得产物在Mw为5200左右时的阻垢率相当。利用SEM对碳酸钙垢型变化的研究结果表明．PASP的加入导致了成垢严重的晶格畸变。     

浅谈青花分水的工艺技法

青花是古代劳动人民在长期的陶瓷生产实践中创造的一种釉下装饰技艺,誉满中外的景德镇青花瓷,它色调明快、兰白相映,给人以赏心悦目的视觉效果。从内容题材上看,即人物、山水、花鸟图案,亦有规则的几何图案组合,在表现形式上有工笔、写意。     

强化科技创新促进结构调整

我国玻纤工业近几年在国家建材局正确领导下,全行业积极努力,在技术进步,产品开发,经营管理等方面都取得了较大成绩."九五"期间,面临东南亚经济危机的影响和世界玻纤生产能力大于需求,以及我国"八五"期间玻纤产量的较大发展情况下,这几年产量基本稳定在18万吨/年水平上.但是产品结构有了较大调整,产品质量有所提高,三座无碱池窑投产,使池窑生产比例从8%增长到20%以上,出台政策淘汰落后的陶土坩埚工艺、限制代铂工艺坩埚生产,从而增加了优质丝、纱的比例.     

微氧水处理技术的特性及应用研究进展

对于传统的好氧和厌氧而言,微氧水处理技术是在克服好氧反应能耗较大,厌氧反应器对于设备要求较高而出现的。微氧过程中包含的反应有短程硝化和反硝化、同时硝化与反硝化、氧化降解等反应,因此微氧水处理技术可以应用于有机物降解和深度处理。由于显著降低了曝气量,又不需要较高的设备要求,因此又是一种节能的技术。     

超纯水电解加工机理及工艺基础

引言 超纯水电解加工是在常规电解加工原理的基础上,利用超纯水作电解液,并采用强酸性阳离子交换膜来提高超纯水中OH-离子的浓度,使电流密度达到足够去除材料的一种新型电解加工工艺方法.     

微波辐照技术的工艺特性及其在水处理中的应用

分析了微波辐照技术的工艺特性及其在水处理中的作用机理,介绍了微波辐照技术用于废水处理领域中的研究状况与应用情况,综述了微波辐照技术用于废水处理的工艺类型及反应效果.结合相关研究与工程应用情况,分析了微波辐照技术在水处理应用中存在的问题,并提出了相应的意见和建议.展望了微波辐照技术在水处理中的发展方向.     

CSt-g-AMPS半干法制备及其结构与吸水性能

以玉米淀粉(CSt)为原料,2-丙烯酰胺-2-甲基丙磺酸(AMPS)为单体,硫酸铵为引发剂,采用半干法工艺制备接枝共聚物(CSt-g-AMPS),利用FTIR、XRD、SEM和TGA-FTIR对产物结构与热性能进行分析。考察反应条件对接枝率和接枝效率的影响,确定了较佳制备工艺条件:单体浓度为15%,反应温度100℃,反应时间20 min。CSt接枝AMPS产物的结晶结构及颗粒形貌已被破坏,成为无定形态的多孔物;在氮气保护的受热过程中,产物的热性能从原淀粉及空白样的快速热分解转为较为平缓的热分解,所接入的磺酸基团能稳定至300℃;产物具有快速吸水能力,饱和吸水倍率达267.53 g/g。     

Sulfonation of polyetheretherketone and its effects on permeation behavior to nitrogen and water vapor

The novel polytheretherketone (PEK-C) prepared from phenolphthalein in our institute is an amorphous, rigid, tough material with good mechanical properties over a wide temperature range. To improve its water vapor permeability for the application of gas drying, PEK-C was sulfonated with concentrated sulfuric acid and transferred in sodium, cupric, and ferric salt forms. Sulfonation degree can be regulated by controlling the temperature and reaction time. Characterization of sulfonated PEK-C in sodium form was made by infrared spectroscopy. Some properties of the sulfonated PEK-C, such as solubility, glass transition temperature, thermal stability, mechanical properties, and transport properties to nitrogen and water vapor, are also discussed. © 1996 John Wiley & Sons, Inc.     

水相添加剂对热可膨胀聚合物微球颗粒结构和膨胀特性的影响

通过戊烷发泡剂存在下的偏氯乙烯-丙烯腈-甲基丙烯酸甲酯(VDC-AN-MMA)悬浮共聚制备包覆型热可膨胀聚合物微球,考察氯化钠、柠檬酸和重铬酸钾等水相添加剂对聚合物微球颗粒结构和热膨胀特性的影响。结果表明氯化钠、柠檬酸和重铬酸钾的添加均可起到降低聚合过程中形成难膨胀聚合物细微粒子的作用,当氯化钠添加量为4%(质量分数,基于单体,下同)、柠檬酸添加量为2.5%～5.0%、重铬酸钾添加量为0.05%～0.1%时,制备的可膨胀聚合物微球具有粒径分布窄、形态规整、聚合物对发泡剂包覆效果好等特点;加热后未膨胀聚合物微粒数目少,膨胀均匀,膨胀温度区间宽。     

Determination of the technological parameters for the sonochemical purification of oily water

Ultrasound allows for the significant intensification of modern technologies, providing for the reduction of their energy capacity and the improvement of the quality of the final product. An experimentally revealed essential increase in the activity of crystals obtained in a galvanocoagulator upon ultrasonic exposure allowed for the elaboration of a new technology for the purification of large amounts of polluted waters in special reaction vessels. At the Institute of General and Inorganic Chemistry of Russian Academy of Sciences, a method for the purification of wastewaters from oil products and heavy metals using a galvanocoagulant as a reagent was developed. To realize this technique, flow drum reactors (galvanocoagulators) operating in a continuous mode by microferritization using magnetite, which is obtained by the electrochemical method directly in the rolling drums, are used.     

Network structure and temperature dependence swelling behavior of PEG-b-Poly (NIPAM-co-AMPSA) hydrogels in water

Temperature sensitive hydrogels were prepared by free radical polymerization of N-isopropylacrylamide (NIPAM) and 2-acrylamido-2-methylpropanesulphonic acid (AMPSA) in presence of polyethylene glycol (PEG) as macroinitiator. The aim of the work reported here was to investigate temperature sensitive swelling and deswelling behaviors of the hydrogels in water in order to investigate the effect of various amounts of AMPSA. The result indicated that the incorporation of a hydrophilic ionizable comonomer (AMPSA) affects the temperature sensitivity, swelling/deswelling, morphology and network structure of the hydrogels. The volume fraction in the swollen state (V_2m), the number average molecular weight between cross-links ([`(M)]_c {\overline M_c} ), the number of segments between the cross-linked point (N), polymer-solvent interaction parameter (χ), enthalpy (ΔH) and entropy (ΔS) were determined using the Flory-Rehner theory at equilibrium swelling. The negative values of ΔH and ΔS showed that the prepared hydrogels had lower critical solution temperature (LCST). The Flory-Rehner theory of swelling equilibrium was qualitatively satisfied with the experimental data of hydrogels at different temperature.     

Molecular dynamics simulation of water transport through graphene-based nanopores: Flow behavior and structure characteristics

The flowbehavior of pressure-drivenwater infiltration through graphene-based slit nanopores has been studied by molecular simulation. The simulated flow rate is close to the experimental values, which demonstrates the reasonability of simulation results. Water molecules can spontaneously infiltrate into the nanopores, but an external driving force is generally required to pass through the whole pores. The exit of nanopore has a large obstruction on the water effusion. The flow velocity within the graphene nanochannels does not display monotonous dependence upon the porewidth, indicating that the flowis related to the microscopic structures ofwater confined in the nanopores. Extensive structures of confined water are characterized in order to understand the flow behavior. This simulation improves the understanding of graphene-based nanofluidics, which helps in developing a new type of membrane separation technique.     

有机皂土的双硫腙修饰及其对水中铅离子的吸附行为

采用十六烷基三甲基溴化铵（CTMAB）对皂土进行改性,用双硫腙对其表面进行修饰,制备了廉价的新型固态吸附剂。用傅立叶变换红外光谱进行了表征。以火焰原子吸收为检测手段,研究了该吸附剂对水中铅离子的吸附行为,计算了吸附过程的焓变(△H),吉布斯自由能变(△G)和熵变(△S)等热力学常数和吸附活化能。结果表明,用CTMAB改性后,双硫腙可牢固的负载于皂土上,制备的固态吸附剂对水中铅离子具有较强的吸附能力。吸附量受介质的pH值,温度和吸附时间的影响。其吸附行为符合Langmuir吸附等温模型和HO准二级动力学方程式。该吸附反应为自发的吸热过程。     

偶氮引发剂对PAN及其原丝结构和热稳定化行为的影响

以丙烯腈和衣康酸为单体,以二甲基亚砜(DMSO)为溶剂,分别以含脒基的偶氮二异丁脒盐酸盐(AIBA)、偶氮二异丁腈(AIBN)为引发剂,采用溶液聚合法,制备了具有不同端基结构的丙烯腈与衣康酸共聚物PAN-AIBA和PAN-AIBN;经湿法纺丝得到聚丙烯腈(PAN)原丝,研究了AIBA,AIBN引发剂的分子结构对PAN相对分子质量、原丝结构、热行为的影响。结果表明:采用溶液聚合的方法,以AIBA为引发剂可制得适于湿法纺丝的PAN-AIBA,其环化反应的起始温度较PAN-AIBN的提前了20℃,放热峰较宽;与PAN-AIBN相比,PAN-AIBA原丝的晶粒尺寸更大、结晶度较高;在低温热稳定化条件下,PAN-AIBA原丝表现出优于PAN-AIBN的较高热环化效率,而在高温热处理时,二者热环化效率相近;通过利用AIBA引发剂在PAN大分子结构中引入脒基,有望改善PAN原丝的低温热稳定化行为。     

论煤泥水系统工艺流程中的局部循环

阐述了炼焦煤选煤厂煤泥水系统工艺流程中存在的几种局部循环形式,并以汾西中兴选煤厂为例,引用循环系数K值分析和评定局部循环对煤泥水系统的影响程度;对局部循环有针对性地实施整改措施,可简化煤泥水系统工艺流程,有利于选煤厂提效降耗。     

旋膜蒸发器及其新型设备与流程

介绍旋转薄膜蒸发器的结构与性能。讨论了原有设备及流程的不足，以及为解决这些不足而开发出的新型设备与流程。     

Relating the molecular structure and crystallization behavior of polypropylene

The crystallization behavior of two polypropylene (PP) resins as used for biaxially oriented polypropylene (BOPP) and general injection mold applications, respectively, has been intensively investigated and compared by means of polarized light optical micrography (POM), differential scanning calorimetry (DSC), conventional transmission electron microscopy (TEM), and high resolution transmission electron microscopy (HRTEM). It is found that both molecular weight distribution and isotacticity of polypropylene strongly affect its crystallization characteristics, e.g., the number of crystal nuclei at the initial stage, crystallization dynamics, the morphology, size and perfection of crystals in the final product, and so on. The results indicate an appropriate molecular structure is vital in producing high‐quality BOPP film. Polym. Eng. Sci. 44:1749–1754, 2004. © 2004 Society of Plastics Engineers.     

New technological process for the manufacture of tire cord and its apparatus design

Conclusions A new technological process for the manufacture of tire cord has been developed and tested under manufacturing conditions and equipment for realizing it which make it possible to prepare high-strength kapron yarn of single-twist structure for the preparation of type 35KNTS-O tire cord fabric.Khimtekstil'mash NPO (Chernigov). Translated from Khimicheskie Volokna, No. 5, pp. 37–39, September–October, 1993.