Preparation and Characterization of Biobased Dehydroabietyl Polyethylene Glycol Glycidyl Ether-Grafted Hydroxyethyl Cellulose with High Emulsifying Property

Dehydroabietyl polyethylene glycol glycidyl ether-grafted hydroxyethyl cellulose(HEC)polymer surfactant(DA(EO)5GE-g-HEC)was prepared using ring-opening polymerization with biobased rosin and hydroxyethyl cellulose as feedstocks.Dehydroabietyl polyethylene glycol glycidyl ether(DA(EO)5GE)was formed by condensation of dehydroabietyl alcohol polyoxyethylene ether(Rosin derivative:DA(EO)5H)and epichlorohydrin.The grafting degree of DA(EO)5GE-g-HEC was manipulated by adjusting the mass ratio of HEC and DA(EO)5GE and confirmed by EA.According to the formula,when m(HEC)/m(DA(EO)2GE)was 1:1~1:5,the grafting rate of DA(EO)5GE in DA(EO)5GE-g-HEC varied from 34.43%to 38.33%.The surface activity and foam properties of DA(EO)5GE-g-HEC aqueous solution were studied.The results showed that with the increase in grafting rate,the critical micellar concentration(CMC)in aqueous solution changed from 1.28 to 0.96 g/L.The results of the thermogravimetric analysis showed that the temperature range of the main stage of mass loss of DA(EO)5GE-g-HEC was 310°C~410°C,and the thermal decomposition processes of the samples with five mass ratios were similar.An oil in water emulsion was prepared by choosing cyclohexane as the oil phase and DA(EO)5GE-g-HEC as the emulsifier.The effect of DA(EO)5GE-g-HEC mass fraction on emulsion particle size and stability was analyzed.The results suggested that when the oil-water ratio was 8:2 with 0.4%emulsifier,the emulsion droplets were the smallest in terms of particle size and were the most stable.The rheological test results showed that the apparent viscosity decreased with the increase in shear rate and showed a typical elastic gel phenomenon.

CO_(2)-Responsive Smart Foams Stabilized by an Extremely Rigid Bio-Based Surfactant

Environment friendly and intelligent surfactants have attracted great attention in recent years.A bio-based CO_(2)responsive surfactant rosin acid dimaleimide choline(R-BMI-C)with an extremely rigid skeleton was prepared using rosin and choline as raw materials by Diels-Alder addition reaction and acid-base neutralization reactions.Its structure was confirmed by IR and^(1)H NMR spectra.The foams’properties of R-BMI-C could be adjusted by bubbling CO_(2)/N_(2)to change the structure of the surfactant.At pH 10.4,R-BMI-C forms an unstable foam with a half-life of 1.5 h.When the pH was reduced to 7.4 by bubbling CO_(2),R-BMI-C forms an extremely stable foam with a half-life of 336 h.The surfactant R-BMI-C changed from bola type to conventional type when bubbling CO_(2).And the internal aggregation structure of R-BMI-C aqueous solution changed from spherical micelles to laminar micelles according to the cryogenic-transmission electron microscope.We know that the lamellar structure tends to adsorb at the air/water interface or is trapped in the foam film,which slows down the foam coarsening and agglomeration process,resulting in a significant increase in foam stability.R-BMI-C could be used in oil extraction,fire-fighting and chemical decontamination due to its excellent foaming,stabilization and defoaming properties.

Synthesis and Properties of Rosin-Based Composite Acrylamide Hydrogels

Hydrogels have been widely applied in agricultural drought-resistance,pollution regulation,drug delivery and so on.Acrylamide(AM)is usually used as raw material to synthesize acrylamide hydrogels.However,inherently low mechanical strength greatly limits their applications in some special areas.Therefore,it is necessary to choose suitable functional monomers to optimize acrylamide hydrogels and improve their mechanical performances.In this paper,a novel acrylamide monomer modified by rosin was synthesized,and then polyacrylamide/rosinbased acrylamide(RAM)composite hydrogels were prepared via free radical polymerization using potassium persulfate as initiator,N,N′-methylene-bisacrylamide(MBA)as a crosslinker.The influence of RAM monomer was investigated in detail.The chemical structure,pore structure,swelling properties,thermal performances and mechanical properties of composite hydrogels were characterized by Fourier Transform Infrared spectrometer(FT-IR),thermogravimetric analysis(TG),scanning electron microscope(SEM),and universal testing,respectively.The results showed that the thermal stability and mechanical property of RAM hydrogels were improved significantly.The compressive strength of RAM hydrogels was increased to 3.5 times than that of AM hydrogels,and the tensile strength was 5.1 times compared with AM hydrogels as well.Moreover,RAM hydrogels exhibited a faster initial swelling rate due to the new pore structure formed after introducing the RAM monomer.

矿物质超细粉在水泥粉体中填充效果的分析

将矿物质超细粉应用于高性能混凝土中。其填充作用可以降低混凝土孔隙率,改善其微观结构和宏观性能,但提高填充效果的途径依然有待探讨。粉体的最紧密堆积要求其粒径分布服从Andrensen方程,而实际水泥粉体的粒径分布则服从Rosin-Rammler-Bennet方程。将实测水泥及矿渣超细粉的微分粒径分布与Andrensen方程微分曲线进行了分析和对比。结果表明:在混凝土中掺入比表面积800 m2/kg矿物质超细粉时.虽然可在一定程度上降低孔隙率。但无法达到最紧密堆积的效果,而就工程实际而言,通过多级填充.将超细粉与更细颗粒的材料,如:硅灰等配合使用是更好的方法。

磨制煤粉粒度组成及其质量分布关系研究

为认识磨制煤粉的粒度特性及灰分、硫分矿物质在各粒度级的分布状况,选取西山煤电公司等三个产地的原煤和内蒙五虎山洗精煤共四个样品,采用小型球磨机在相同条件下分别进行了制粉实验,通过对磨制煤粉的粒度特性进行测试分析,证实了磨制煤粉的粒度组成均符合Rosin-Rammler粒度特性方程;该方程的参数k和b分别反映了煤样的可磨性和磨粉产品的细度,洗精煤的k值明显高于原煤.各粒度级的灰分和硫分实验结果表明:粗粒级煤粉的灰分均较高,而硫分在各粒度级中的分布同煤种有关,缺乏普遍规律可循.

不同煤粉燃烧对一次颗粒物排放特性的影响

在实验室条件下,以沉降炉作为燃烧设备,用8级Andersen粒子撞击器分离并收集燃烧后的颗粒物,研究了3种煤粉燃烧后生成的一次颗粒物中可吸入颗粒物排放的特性.结果表明,煤粉燃烧后,PM10、PM2.5、PM1的排放量并不是煤中灰分、固定碳或挥发分的单一函数.用Rosin-Ramm ler函数对一次颗粒物的质量-粒径分布进行曲线拟合,并计算了其中PM2.5/PM10、PM1/PM2.5的值.结果显示,灰分较高的煤粉生成的PM2.5/PM10、PM1/PM2.5值较高,灰分含量低的煤粉生成的PM2.5/PM10、PM1/PM2.5值较低.但PM2.5/PM10、PM1/PM2.5的值与灰分含量并不成正相关性.分析认为,不同煤粉中组分形式和含量的不同,影响了煤粉燃烧后一次颗粒物形成的过程,造成一次颗粒物排放特性的不同.

新拌水泥浆体中邻近胶凝材料粒子表面最近间距分布的解析解

依据Torquato的最邻近表面函数公式,推导了新拌水泥浆体邻近水泥粒子表面最近间距分布的解析解,并采用计算机模拟生成了1个水泥浆体结构模型,选取邻近粒子表面最近间距概率密度分布曲线、区间概率曲线和累计概率分布曲线这3个函数检验模拟结果与理论结果之间的差别。结果表明,该解析解与计算机模拟实验结果吻合良好。利用该解析解,以Rosin-Rammler分布为例,研究了胶凝材料细度以及水胶比对邻近水泥粒子表面最近间距分布及其平均值的影响。结果显示,水泥细度对邻近粒子表面最近间距平均值的影响高于水胶比的影响。邻近粒子表面最近间距解析解的获得,不但为基于不同粒径分布以及尺度范围粉体之间搭配的高粉体初始堆积密度的实现提供了依据,而且对多尺度模拟方法中选取各级模型的尺度、量化粉煤灰浆体中粉煤灰颗粒的微集料效应、了解邻近集料间的交互作用程度以及界面重叠程度等问题具有参考价值。

原生煤粉粒度特性的研究

认识和把握原生煤粉的粒度特性是对其进行有效分选的前提,对采自兖矿集团济二、济三矿各2个工作面的4个煤样进行了原生煤粉的筛分试验。通过研究分析原生煤粉的粒度组成规律,证实了原生煤粉的粒度特性均符合Rosin-Rammler粒度特性方程,并均具有显著的线性相关关系;发现原生煤粉的Rosin-Rammler方程中的参数k与平均粒度d之间存在线性关系,参数b随着参数k的增大而减小。

金刚石绳锯切割花岗石过程中岩屑粒度分布研究

对三种不同花岗石绳锯切割过程中不同弧区位置的岩屑进行了采集，并对其粒度进行了分析。实验结果表明：三种花岗石岩屑粒度分布曲线均大致为单峰分布，符合罗辛一拉姆勒分布规律，大部分岩屑颗粒尺寸集中在20～100μm之间，花岗石岩屑的粒度分布不仅与加工弧区的长度有关，还受到花岗石的原始粒径的影响。

Rosin-Rammler分布的实验拟合曲线优化

基于Rosin-Rammler分布函数,提出一种新的实验拟合曲线优化方法,以二氧化硅、钾长石粉、矿石粉和石英砂四种材料为例,对激光粒度仪实验测量数据进行分析和处理,并应用Matlab软件编程实现实验数据分析和处理自动化。拟合曲线、误差分析和文献对比结果表明,优化方法正确、合理,优化后的拟合曲线更接近实验测量曲线。该方法对于准确计算平均粒径和方差、客观评价粉体材料性能等实际应用具有重要意义。

Synthesis and Kinetics of Hydrogenated Rosin Dodecyl Ester as an Environmentally Friendly Plasticizer

The plasticizer is an important polymer material additive.Non-toxic and environmentally friendly plasticizers are developed recently in order to decrease fossil fuel reserves,serious environmental pollution and the toxicity of phthalate esters.In this study,a new,efficient and environmentally friendly plasticizer of hydrogenated rosin dodecyl ester was prepared by an esterification reaction of hydrogenated rosin and dodecanol.The influences of different reaction conditions(including different catalysts,the catalyst concentration,the ratio of the reactants,reaction temperature,and reaction time)on the esterification yield are examined and discussed.Hydrogenated rosin dodecyl ester with 71.8%yield was synthesized under the optimized reaction conditions(1:0.8 molar ratio of rosin to dodecanol,1 mol%tetrabutyl titanate concentration,and 210℃for 6 h).The esterification reaction is a second-order reaction,and kinetic calculations showed that the activation energy is 39.77 KJ·mol^(−1).The structure of the hydrogenated rosin dodecyl ester was confirmed by FT-IR spectroscopy and^(13)C NMR spectrum.Besides,the thermal stability of target product(hydrogenated rosin dodecyl ester)was also tested by thermal gravimetric analysis(TGA),which showed a good thermal stability.

基于二维直方图构建的图像边缘提取算法实现

针对部分采用一维直方图法和一些改进的二维直方图法,采用阈值法分割图像,实现图像边缘特征提取的算法进行分析,找出这些算法中存在的问题,提出一种基于二维直方图构建确定阈值,并与Canny算子结合的图像边缘提取算法。研究中抓住阈值确定与边缘特征提取两个关键环节,通过对典型的Otsu和MSA等阈值算法进行分析,以一维Rosin算法为基础,通过构建二维直方图,设计以像素灰度值与像素邻域平均灰度值结合的、以阈值权重为参量的阈值选取数学模型;通过对Canny算子具备的图像边缘特征提取占有的优势进行分析,在理论上证明所提出算法的可行性和优越性。通过仿真实验表明,该算法不仅易于实现,还具有较强的实用性,且运算效率较高。

FUNCTIONS OF POLYAMINES IN ROSIN SIZING UNDER NEUTRAL PAPERMAKING CONDITIONS

Functions of the polyamines in neutral rosin sizing were investigated using X-ray photoelectron spectroscopy (XPS) and laser diffraction particle analysis. The polyamine with a higher charge density and a smaller unite size could retain more rosin and cover larger fiber surfaces. The XPS spectra demonstrated that polyallylamine (PAAm) and polyvinylamine (PVAm) could react with a rosin size to form a -OC-N-CO- structure, but polydimethylamino ethyl methacrylate (PDMAEMA) could not. The formation of this structure may be a key step for effective sizing.

格陵兰冰盖次表面湖多源遥感监测——以格陵兰中西部流域为例

格陵兰冰盖在夏季会发生剧烈融化,融水在低洼处汇集形成冰面湖,储存了大量的融水,在冰盖的水文系统中起着至关重要的作用,是格陵兰冰盖质量平衡的重要组成部分.近期有研究发现大量的冰面湖在冬季不会完全冻结,而是掩埋在雪层或冰层下以液态水形式存在,形成冰盖次表面湖.冰盖次表面湖对格陵兰冰盖稳定性和物质平衡会产生重要的影响.由于次表面湖存在于冰盖表层之下难以通过可见光影像进行提取和分析,次表面湖的监测成为次表面湖研究的难点之一.本研究提出一种利用Landsat8和Sentinel-1数据自动提取次表面湖范围的方法.该方法先利用可见光影像提取夏季冰面湖的范围对SAR影像进行掩膜,再根据冬天水体和冰面的后向散射具有可分性的原理,通过Rosin阈值分割算法,提取得到2018—2019年冬季格陵兰中西部流域的次表面湖并对其分布进行分析.在研究区内选择10个测试区域,利用该方法对区域内的次表面湖进行目视解译,并对算法自动提取次表面湖结果进行精度验证.结果表明,本研究提出的自动提取算法Kappa系数为0.85.基于该方法,本研究在2018年格陵兰中西部流域共提取夏季冰面湖的面积为102.28 km~2.约43.09%的夏季冰面湖不会完全冻结,从而在冬季形成次表面湖(面积为44.07 km~2).

Development and Characterization of an Electrochemical Sensor for Cinchonidine Detection Based on Molecularly Imprinted Polymer with Modified Rosin as Cross-linker

Molecularly imprinted polymers（MIPs） were applied as molecular recognition elements to an electro- chemical sensor for cinchonidine（CD）. A kind of MIP was synthesized with cinchonidine as template, modified ro- sin（ethylene glycol maleic rosinate acrylate） containing the skeleton of phenanthrene rings as cross-linker and me- thylacrylic acid as functional monomer. MIP membrane was prepared on a glassy carbon electrode for the determina- tion of CD via free radical polymerization method. Electrochemical impedance spectroscopy（EIS） and cyclic vol- tammetry（CV） were used to characterize the membrane electrochemical behavior in electrode fabrication process. The experimental conditions were discussed. Under optimum conditions, it was found that the response of peak cur- rents was linear to the concentration of CD in a range of 0.013-2.26 mmol/L. The detection limit for CD is 1 μmol/L the relative standard deviation for 100 μmol/L CD is 1.34% and the incubation time is 2 min. The sensor was applied to the determination of CD in urine samples with satisfactory results.

The effect of rosin acid on hydrodeoxygenation of fatty acid

In this study, inhibition of tall oil fatty acid hydrodeoxygenation(HDO) activity due to addition of rosin acid over sulfided Ni Mo/Al_2O_3 was investigated. Oleic acid and abietic acid were used as model compounds for fatty acid and rosin acid respectively in tall oil. After completion of each HDO experiment,the Ni Mo catalysts were recovered and used again under the same conditions. The results showed that the oleic acid HDO activity of sulfided catalysts was inhibited by addition of abietic acid due to competitive adsorption and increased coke deposition. The rate of carbon deposition on the catalysts increased when abietic acid was added to oleic acid feed. Moreover, the coke was in a more advanced form with higher stability for the catalysts exposed to both oleic acid and abietic acid. Furthermore, a clear correlation between the rate of coke formation and concentration of abietic acid was observed.

Water Repellency of Cellulosic Fibrous Mats Impregnated with Organic Solutions Based on Recycled Polystyrene

Recycled polystyrene in combination with paraffin wax,alkyd resin,and gum rosin were used as components in formulations to investigate their water repellency when applied to cellulosic filter paper substrates.Polystyrene was used in concentration of 5,10,15 and 20%,alkyd resin and gum rosin of 5%each and paraffin wax of 0.5%.Totally,twenty four water repellent solutions were prepared.Water repellency was evaluated in terms of water absorption of the cellulosic fibrous mats.The relations between retention of solid substances of the formulations and grammage and water absorption of filter paper samples were also determined.The results showed that all the water repellent formulations exhibited a degree of water repellency.Water absorption decreased by increasing the polystyrene concentration in the solution and polystyrene retention by the impregnated filter paper samples.The incorporation of 0.5%paraffin wax improved the hydrophobicity of treated samples.The best of the three water repellent formulations including paraffin wax was found to be the“polystyrene+gum rosin+paraffin wax”solution followed by the“polystyrene+alkyd resin+paraffin wax”and“polystyrene+paraffin wax”solution.The inclusion of 5%gum rosin in polystyrene solutions compared to that of 0.5%paraffin wax was found more effective in almost all cases.

运动学一例题的探讨

在理论力学教材中有这样一道运动学例题:小船 M 被水冲走后,用一绳将它拉回岸边A点。假定水流速度 C1沿河宽不变,而拉绳子的速度则为 C2。如小船可以看成一个质点,求小船的轨迹。

常量代换在解题中的应用

一.用模式“M/M”代换“|”例1.已知a+b+c=0,求证: a(1/b+1/c)+b(1/c+1/a)+c(1/a+1/b)+3=0证明:a(1/b+1/c)+b(1/c+1/a)+c(1/a+1/b)+3 =a(1/a+1/b+1/c)+b(1/a+1/b+1/c)+c(1/a+1/b+1/c)

喷油螺杆压缩机用油气分离器滤芯出口孔径对分离特性的影响

采用大涡模拟分三种出口孔径的模型,对喷油螺杆空压机用油气分离器滤芯的一次分离筒内的流场进行了对比分析.结果表明:出口孔径的尺寸对切向速度和轴向速度分布有一定的影响;对自由涡和强制涡区域、上行流下行流的数值、二次流的程度和油滴的分布等均产生一定的影响;综合各项因素可知,2 mm出口孔径有较好的分离效果.