PPH治疗混合痔的护理体会

目的探讨混合痔行PPH的护理方法。方法99例混合痔患者均行PPH,手术前向患者介绍住院环境、住院须知,告知治疗方法及护理上需要的配合,饮食、排便的注意事项,术前准备等;术后体位及恢复饮食时间,大小便情况观察及各种外用药的使用,出血护理及伤口护理,肛门功能锻炼;制定入院评估,印制出院指导。结果99例患者痔核明显回缩,顺利出院。结论混合痔PPH的术前术后护理对患者顺利康复有重要意义。     

Crosslinking of styrene-butadiene rubber with polyurethanes bicapped with benzyocyclobutene

Summary A polyurethane prepared from 1,9-nonanediol and toluene-2,4-diisocyanate with M_n=11,840, was capped on both ends in a reaction with 4-(benzocyclobutenyl) methanol. The polyurethane was used to crosslink styrene-butadiene rubber through Diels-Alder reactions on the benzocyclobutene functionality. The synthesis and characterization of 4-(benzocyclobutenyl) methanol, a molecule not reported previously, is presented. The crosslinking reaction was carried out on intimate mixtures of the telechelic polyurethane and SBR at elevated temperature and pressure. Various physical properties of the crosslinked material were studied.Work done at the Department of Chemistry, University of Akron, Akron, OH 44325, USA     

Dehydrochlorination of propylene chlorohydrin with sodium hydroxide and with catholyte

Dehydrochlorination of an aqueous solution of propylene chlorohydrin with sodium hydroxide (12·5 and 30% by weight), with catholyte (5 or 10% by weight NaOH + 14% by weight NaCl) and with milk of lime (15% by weight) were compared. The use of catholyte (10% by weight NaOH + 14% by weight NaCl) enables propylene oxide to be obtained in a yield of 94·3%, with 100% conversion of chlorohydrin. The concentration of 1,2-propylene glycol in the waste is 0·07% by weight.     

复合扰流柱的螺旋内构件反应器内流体的宏观混合

在管式反应器内插入复合扰流柱的螺旋型内构件,采用脉冲示踪法测定了反应器内流体的停留时间分布,研究了器内流体的宏观混合特性,分析了该内构件强化混合的机理. 结果表明,复合扰流柱的螺旋型内构件反应器内的流体流动更接近于活塞流,其轴向扩散模型参数Pe为螺旋型内构件反应器的1.02~1.28倍,为不带内构件反应器的1.35~1.77倍. 复合扰流柱的螺旋型内构件能显著增强器内的二次流动,从而强化了宏观混合效果.     

Reaction of CH-acidic compounds with thiacumulenes and alkylation with dihaloalkanes

Dithiocarboxylation of CH-acidic compounds 1 and stepwise alkylation of primarily formed dithiolates 2 yielded ketene dithioacetals 5a,b or methylenebis(dithiocarbonates) 12a–c. Reaction of 5a,b with nucleophiles afforded thiophene 7 and dithioacetals 8, 9a,b, 11, respectively. 1,3-Thiazetidines 14a,c,e and thiazolidines 14b,d,f were prepared by thiocarbamoylation of 1b,c,e and subsequent alkylation with dihaloalkanes.     

Copolymerization of acrylonitrile with maleamic acid derivatives and with carboxyphenylmaleimide

Acrylonitrile was copolymerized with two N-arylmaleamic acids and with N-3-carboxyphenylmaleimide in dimethylformamide (DMF) using azobisisobutyronitrile as initiator. The reactivity ratios and the Q-e parameters of these monomers were estimated, and the resulting copolymers were characterized by viscosity measurements and thermal analysis. Thermogravimetry and differential thermal analysis data showed an improvement in the thermal behaviour of the investigated copolymers compared with that of poly(acrylonitrile). Mechanisms illustrating the role of both the acidic group and the maleimide ring in the nitrile oligomerization were proposed. The produced copolymers showed an excellent affinity towards basic dyes and better color fastness towards UV light.     

Syntheses of bismaleimides with ester units and their polymerization with diamines

Five structurally different bismaleimides were synthesized by reaction between 3(4)‐maleimidobenzylchloride with various diphenols. They were characterized by infrared (IR) and proton nuclear magnetic resonance (¹H‐NMR) spectroscopy. Thermal characterization of monomers and their polymers was accomplished by differential scanning calorimetry (DSC) and dynamic thermogravimetric analysis (TGA). Polyaminobismaleimides having inherent viscosities of 0.1–0.4 dL/g were prepared by Michael addition of diamines to bismaleimides. The polymers are soluble in solvents as DMF, NMP, and DMSO, and afforded film from their solutions. © 2002 John Wiley & Sons, Inc. J Appl Polym Sci 84: 750–757, 2002; DOI 10.1002/app.10294     

单双切向环流式旋风除尘器的比较

以粉煤灰 空气为实验物系 ,测定了单、双切向环流式旋风除尘器的除尘效率和压降。实验结果表明 ,双切向环流式旋风除尘器的除尘效率比单切向环流式旋风除尘器的除尘效率有所提高 ,压降比单切向环流式旋风除尘器的压降低 2 0 0Pa ,处理量有所增大     

Wettability enhancement of polystyrene with electron cyclotron resonance plasma with argon

Polystyrene cell‐culture substrates were treated with argon glow discharge to make their surfaces hydrophilic. The process was novel in that it used a microwave electron cyclotron resonance (ECR) source for polymer surface modification. The substrates were processed at different microwave powers and time periods, and the surface modification was assessed with by measurement of the water contact angle. A decrease in contact angle was observed with increasing microwave power and processing time. Beyond a certain limit of power and duration of exposure, however, surface deterioration occurred. The optimum conditions for making the surfaces hydrophilic without deterioration of the samples were identified. The plasma parameters were assessed by Langmuir probe measurement. Fourier transform infrared spectroscopy with attenuated total reflectance showed evidence for the induction of hydrophilicity on the surface. The surface micromorphology was examined with scanning electron microscopy. The results prove that the ECR glow discharge was an efficient method for enhancing the wettability of the polymer surfaces. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 1618–1623, 2003     

聚四氟乙烯修饰的MCM-49分子筛上苯与丙烯烷基化反应

制备了MCM-49分子筛负载25％聚四氟乙烯催化剂,将催化剂应用于苯与丙烯烷基化反应.结果表明,反应温度＜150℃时,表面疏油性催化剂可以使反应中由丙烯聚合生成的油性大分子和多异丙苯较快的从催化剂表面脱附,减少了油性大分子对催化剂活性中心的覆盖,减少积炭生成,提高了催化剂寿命.     

Reinforcement of polypropylene with lignocellulose nanofibrils and compatibilization with biobased polymers

Freeze‐dried and milled lignocellulose nanofibrils (LCNF) were used to reinforce polypropylene (PP) nanocomposites. The LCNF, containing up to 9% lignin, was obtained from residual Empty Palm Fruit Bunch (EPFB) fibers. Soy protein isolate (SPI) and hydroxypropyl cellulose (HPC) were tested as coupling agents as well as maleic anhydride grafted polypropylene (MAPP), which was used as a reference. A good level of dispersion of LCNF in the PP matrix while mechanical testing and thermal analyses indicated an improvement of the thermo‐mechanical behavior of the nanocomposites was revealed upon loading of the lignin‐containing nanofibrils. The tensile modulus of PP was increased by 15% upon the addition of 1% LCNF with SPI as a compatibilizer. Likewise, the thermal stability of the composites was most markedly enhanced. Overall, LCNF and SPI, two important bioresources, are introduced here for the development of novel and cost‐effective PP‐based composites. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43854.     

AN-VA-MAS体系与AN-VA体系两种腈纶生产情况的对比

通过对聚合物和纤维的主要质量指标以及聚合釜生产能力变化的对比分析,说明了在腈纶生产中,使用AN-VA-MAS三元体系的聚合工艺优于AN-VA的二元体系聚合工艺.     

Laser protection with optical limiting by combination of polymers with dyes

Lasers are becoming more and more common and can damage eyes and sensors, so arise the need for efficient protection. A possibility is the use of filters with optical limiting abilities. Optical limiting leads to a reduced transmittance of these filters above a certain light energy. Solid-state optical limiting filters consist frequently of poly(methyl methacrylate) (PMMA). Using dyes is an often used way to provide optical limiting qualities to polymers. PMMA does not offer the possibility to attach the dye covalently to the polymer chain. Poly(lactide), also a transparent polymer, has so far not been used for filters for optical limiting. Its polymerization mechanism offers a simple possibility to a covalent binding of the dyes, by using them as initiator. This should be, like the attaching of big side groups to dyes, a possibility to increase stability of dyes against aggregation. Hybrids out of polymers and dyes and filters thereof could be produced. The polymers were analyzed by nuclear magnetic resonance, gel permeation chromatography, and nonlinear optical measurements. Including azophloxine leads to an attenuation of the laser beam in the range of 10⁻³ and Eosin B even to 10⁻⁵. The eosin sample shows a two magnitudes better attenuation then usual guest–host systems like poly(methyl acrylate) with carbon nanotubes. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47150.     

微反应器耦合离子液体强化萃取过程的研究进展

离子液体作为一种绿色溶剂在强化萃取过程中获得了广泛的应用，但是高昂的生产成本以及以高黏度为特征的流体力学性质阻碍了其工业化应用。微化工技术为基于离子液体的连续化萃取提供了一种高效的过程强化平台。近年来，微化工技术与离子液体技术的耦合强化在萃取分离领域越来越受到关注。本文主要综述了微流动萃取技术的基本现状、离子液体参与的萃取过程特征、微反应器内涉及离子液体的互不相溶液-液两相流型、传质及其强化机制，重点介绍了微反应器在基于离子液体萃取金属、有机物等过程中的应用、微流动萃取过程放大的研究进展，并对涉及离子液体的多级萃取、功能化离子液体的萃取应用及其相应的微流动萃取放大等研究方向进行了展望。     

氯胺消毒及高锰酸钾氯胺联用消毒

以城市污水处理厂二级出水为试验水样,观察了氯、氯胺单独消毒工艺以及高锰酸钾与氯胺协同消毒工艺的消毒效能,同时比较了投药总量相同条件下单独氯胺消毒工艺及高锰酸钾与氯胺协同消毒工艺的消毒效能以及对THMs生成的影响。结果表明,对于污染严重,尤其是耗氯物质含量较高的污水,氯消毒效果受到极大影响,氯胺消毒的效果要略好于氯消毒的效果,而高锰酸钾与氯胺协同消毒工艺的消毒性能明显优于单独氯胺消毒工艺,并且能够进一步降低THMs的生成量。因此,高锰酸钾与氯胺协同消毒工艺可以使处理后水质从微生物安全性到化学安全性两方面均得到提高。     

中间层为聚吡咯的复合电极深度处理焦化废水

电催化技术深度处理焦化废水仍受极板导电性和催化活性制约而无法广泛应用。本文在以掺杂锑的二氧化锡的钛网（Ti/SnO₂-Sb）为底层、以掺杂铈的二氧化铅（PbO₂-Ce）为顶层的二维结构之间插入良好导电性的非离子型高聚化合物聚吡咯（PPy）,形成具有三维结构的Ti/SnO₂-Sb/PPy/PbO₂-Ce电极能够增加电流效率,提高催化活性。分别通过X射线衍射图谱、高分辨率透射电子显微镜、X射线光电子能谱和热重分析来表征电极的结构、元素的化学状态和热稳定性,通过线性扫描伏安法和循环伏安法测试电极的电化学表面行为。分析表明,铈的掺杂使极板羟基自由基（·OH）产生量有较大增幅;PPy中间层的插入增强了电极热稳定性,使电流效率提升至7.55%。电化学分析表明Ti/SnO₂-Sb/PPy/PbO₂-Ce电极具有较高的活性表面积和析氧电位。为使极板达到最佳应用条件,通过响应面法得到一组预测优化参数：电流密度161.18A/m²,电解质浓度5.90g/L,极板间距1.58cm,初始pH为9.05。在最优条件下,对焦化废水的降解效率达到90.47%,能耗为0.787kW·h/g,并据此对可能得催化氧化原理提供预测。     

Synthesis and characterization of block-copolymer surfactants with specific interactions with associative thickeners

It has been theorized that, in order to get some positive interaction with the associative thickeners, the surfactants should have, at the end of the hydrophilic sequence, a short hydrophobic group. On the other hand, in order to control the hydrophilic lipophilic balance (HLB), it is wise to use well controlled polymerization procedures to build the block-copolymer. Then, the safer and simplest way to reach such goal is to use the ring-opening living anionic polymerization of butylene oxide (hydrophobic sequence) and then ethylene oxide (hydrophilic sequence); this living block-copolymer is then killed using an alkyl or aryl chloride (or bromide). However, because such surfactants include at the end of the hydrophilic sequence a hydrophobic group, they tend to adopt, when adsorbed onto hydrophobic latex particles, a back-folded conformation. In order to get for them an extended conformation, the hydrophilic sequence should have charges able to repel each other. This was achieved upon preparing block-copolymers of acrylic acid and butylacrylate, using a controlled radical polymerization with reversible addition fragmentation transfer (RAFT) agents, starting with the poly(acrylic acid) (PAA) sequence. Then, the radical fragment coming from the RAFT agent is at the end of the PAA sequence. A few rheological data actually confirm the interest of the concept.     

Surface characterization of wood treated with boron compounds combined with water repellents

Longer weathering exposure periods are more reliable for end‐use performance evaluations of wood surfaces. This study aimed to investigate the effect of boron impregnation on the surface composition and color of Scots pine (Pinus sylvestris L.) wood exposed to 18 months of natural weathering in the West Black Sea Region of Turkey. All measurements were performed at 6 month intervals. Samples were first impregnated with boron compounds and then for a second time using five different water‐repellent materials. Polyethylene glycol and aluminum sulfate were introduced with the boric acid as single impregnations. With increased weathering time, the samples darkened, while sodium silicate kept the color change to a minimum. Nano boron‐impregnated samples exhibited more effective results than those impregnated with boric acid. The FTIR analysis results demonstrated that the impregnation process had caused significant changes in the chemical structure of the samples. The changes in the chemical structure of the wood resulting from the impregnation process were partially maintained during the weathering.