Surface activity and cleaning performance of rosin-based quaternary ammonium salt type asymmetric Gemini surfactants

Rosin,a renewable and abundant resource,has been extensively processed and chemically modified to endow it with special properties,especially in the surfactant industry.In this study,four rosin-based quaternary ammonium asymmetric gemini surfactants(RGS-2-n)with different alkyl chain lengths(n=12,14,16,18)were synthesized using a simple two-step method based on dehydroabietylamine as the raw material.The feasibility of these surfactants for cleaning purposes was comprehensively evaluated,suggesting that the surfactants own high surface activity and good cleaning performance.Furthermore,by successfully introducing the amine group of dehydroabietylamine into the hydrophilic group of the surfactants,we avoided its potential harm to the environment and water pollution.Density functional theory proves rosin-based gemini surfactants with asymmetric structure can further improve cleaning efficiency.Overall,our findings suggests that RGS-2-n surfactants are promising and sustainable candidates for cleaning electric plates,and provide new opportunities for rosin application in the electric industry.

基于Rosin-Rammler的离散元扩大头抗浮锚杆抗拔力学特性影响研究

目前,抗浮锚固技术已被广泛应用于工程建设中。然而,学界对扩大头抗浮锚杆与不同级配土体相互作用的力学机制的研究尚不充分。因此,文章针对扩大头抗浮锚杆与土体级配的相互作用展开了研究。首先通过Rosin-Rammler函数构建级配曲线,并以曲线形状参数m值表征土体颗粒的不均匀性,然后进行拉拔数值模拟。结果表明,在拉拔过程中,m值越大,土体颗粒越不均匀,并且拉拔承载力随着m值的增大而减小。同时,速度传递区域由类锥形转为类矩形分布,接触力链由粗支网状转为细支网状。

运用Rosin-Rammler分布函数研究煤尘粒径分布规律

运用Rosin-Rammler分布函数对伯方煤矿3#煤层煤样进行粒径分布情况的分析,得出结论:在双对数lnd-ln{-ln[1-F(d)]}坐标系下,所研究的材料颗粒分布的回归曲线为一条直线,R2=0.9672,线性回归良好。并得到了所研究粒径分布的具体函数表达式。由此可以对该煤层的冲击产尘的粒径分布有一个总体上的量化认识,为指导实际生产降尘、除尘提供了理论上的依据。

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。

基于Rosin-Rammler的海水冷却塔收水器流体力学性能研究

收水器是控制海水冷却塔性能及环境影响的重要塔内件。为探索其内部流动特征对性能的影响,采用试验与计算流体力学(CFD)方法,对海水冷却塔收水器流体力学特性进行研究。文中设计了海水冷却塔收水器压降性能的测试装置并对BO-45/160型收水器进行测试,运用Rosin-Rammler函数描述收水器内部液滴群的粒径分布,通过SST k-ω湍流模型及离散相(DPM)模型,建立CFD计算模型,与试验测试结果对比,模拟值与试验值达到较好的吻合效果,证明了CFD模型的准确性。随后,通过CFD方法考察波形、双波形、折线形收水器基本流道片型在多间距多高度条件下的流动形式,分析不同收水器型式在不同间距和高度下收水效率与压力降的影响因素,为新结构的开发提供数据支撑。

用双 Rosin-Rammler 函数求颗粒尺寸分布

用双Ｒｏｓｉｎ－Ｒａｍｍｌｅｒ分布函数不但可以求解具有双峰形式的颗粒尺寸分布，而且也可以求解具有单峰形式的实际颗粒系．模拟计算和实测表明，即便是求解单峰分布的颗粒尺寸，用双Ｒｏｓｉｎ－Ｒａｍｍｌｅｒ分布函数也明显比常用的单Ｒｏｓｉｎ－Ｒａｍｍｌｅｒ函数具有更高的反演算精度．

Sonochemical Synthesis of Maleated Rosin

The cycloaddition reaction of rosin and maleic anhydride under ultrasonic irradiation has been investigated. The results show that both isomerization and Diels-Alder cycloaddition reactions were accelerated remarkably. The sonochemical reaction reached equilibrium in 5-10 min at 110℃, comparing with regular synthesis of 4-5 h over 180℃.

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.

Synthesis, characterization and application of a dispersant based on rosin for coal-water slurry

A rosin derivative and maleopimaric acid diethanolamide(MAD), was synthesized, characterized by FTIR and1 H NMR, and applied as dispersant for the coal-water slurry(CWS) prepared from Chinese Shenfu coal. The CWS application performance investigation shows that the MAD dispersant has better abilities in reducing CWS viscosity and stabilizing the slurry than a commercial dispersant—sulfonated naphthalene-formaldehyde condensate(SNF). The physicochemical property investigation of the two tested dispersants shows that the adsorption amount of the MAD at coal-water interface is much larger than that of SNF, and the MAD has better wetting property than the SNF on the coal surface. It indicated that the excellent capabilities of MAD are related to the adsorption mode of standing upright on the coal surface. Based on the above, the mechanism of dispersion and stabilization of the CWS prepared from MAD dispersant is presented.

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.

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.

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.

基于二维Rosin阈值方法的道路裂纹边缘检测

为了在道路裂纹图像边缘检测时选择准确的区分噪声与边缘阈值,针对一维Rosin算法不能充分利用图像局部结构信息的缺陷,将传统Rosin方法推广至二维,联合Canny边缘检测算法和Rosin算法,利用像素点本身及其邻域的局部结构信息建立图像二维直方图;利用直方图的最高点和最低点构造全角旋转阈值选取平面,以搜索直方图与各阈值平面的空间距离最大值确定阈值点,获得一种自适应的Canny算法中的阈值选取方法。研究结果表明:该算法可对道路裂纹边缘进行有效检测,并扩展Canny算法的应用范围。

基于Rosin-Rammler函数的数值模拟对旋风除尘器粒径分布规律的研究

将试验室的一组颗粒进行筛分,运用Rosin-Rammler分布函数对所得到的颗粒累积粒径分布进行拟合,计算所得结果与实际的粒径分布具有较好的拟合性。将计算得到中位径和传播系数代入到fluent中进行数值模拟,得到的不同粒径的颗粒分布与试验数据有较好的吻合性,从而说明该颗粒分布模拟的可靠性;通过计算分级效率可以得出除尘器捕捉5μm以上的颗粒效率较高,与试验较为吻合,同时该结论为旋风除尘器不同粒径的数值模拟提供了参考依据。

Curing kinetics and mechanical properties of bio-based composite using rosin-sourced anhydrides as curing agent for hot-melt prepreg

In this study, a novel bio-based thermosetting system has been developed from epoxy resin （EP）, with rosin-sourced anhydrides （maleopimaric acid, RAM） as curing agent and imidazole type latent catalyst （two amino imidazole salt complex, IMA）, to be used as matrix for hot-melt prepreg curing at mid-temperature. For comparison, the epoxy resin system with petroleum sourced hardener methylhexahydrophthalicanhydride （MHHPA） was also examined. The curing behaviour and mechanism were investigated by non-isothermal differential scanning calorimeter （DSC） analysis and Fourier transform infrared （FTIR） spectra. The results showed that the curing course of bio-based epoxy resin system containing RAM included two stages, which were the reaction between the free carboxyl group of RAM and oxirane ring under the acceleration of IMA, and the main reaction attributed to the reaction between anhydride and oxirane. According to Kissinger method, the reaction activation energy （E,） of two stages were 68.9 and 86.5kJmo1-1, respectively. The Eo of EP/MHHPA and EP/IMA resin system were 81.04 and 77.9kJmol-I. The processing property of EP/RAM/IMA system, i.e. the relationship between viscosity-temperature-time, was characterized by cone-plate viscometer aim to decide the processing parameter ofprepreg preparation. The effect of RAM content on mechanical performance and dynamic mechanical property was investigated. Noteworthily, compared with the laminates with EP/MHHPA as matrix, the laminates with RAM as hardeners achieved a 44%, 73% and 70℃ increase in bending strength, bending modulus and the glass transition temperature, respectively, due to the bulky hydrogenated phenanthrene ring structure incorporated into the cross-linking networks. When the fiber volume fraction reached 47%, the mechanical property of the laminates prepared with hot melt prepreg was superior or comparable to that of composites with pure petroleum sourced matrix. RAM as cross-linking agent of epoxy resin holds a great potential to satisfy the requirement of composites such as structure and secondary structure parts preparation.

Synthesis of multifunctional monomers from rosin for the properties enhancement of soybean-oil based thermosets

Two kinds of rosin derivatives, （2-hydroxy-3-（methacryloyloxy）propyl 7-isopropyl-1,4a-dimethyl-1,2,3,4,4a,4b,5,6,10,10a- decahydrophenanthrene-1-carboxylate） （HMPIDDC） and （（（7-isopropyl-1,4a-dimethyl-1,2,3,4,4a,9,10,10a-octahydrophenan- thren-1-yl）methyl）azanediyl）bis（2-hydroxypropane-3,1-diyl）bis（2-methylacrylate） （IDOMAHM） were synthesized under mild and easy to implement conditions. The two derivatives were employed as the rigid monomers to copolymerize with acrylated epoxidized soybean oil （AESO）, as so to improve the performance of the cured resins. The chemical structures of HMPIDDC and IDOMAHM were confirmed by nuclear magnetic resonance （NMR） and Fourier Transform Infrared （FT-IR） before copolymerization. The curing behaviors of pristine AESO, AESO/HMPIDDC blend, and AESO/IDOMAHM blend were monitored by differential scanning calorimetry （DSC）. Moreover, the thermal and mechanical properties of the cured resins were evaluated by universal mechanical testing, dynamic mechanical analysis （DMA） and thermogravimetric analysis （TGA）. The results demonstrated that after the introduction of HMPIDDC and IDOMAHM, the glass transition temperature and mechanical properties of the copolymerized resin were significantly increased. In one word, HMPIDDC and IDOMAHM showed dramatic potential to be used as bio-based compounds to improve the properties of soybean-oil based thermosets.

Preparation and Characterization of Ester from Rosin Acrylic Acid Adduct and Hydroxyethyl Methacrylate

1 Results Rosin is a sort of important renewable resources,which is a foremost product of our country forestry. It has very important meaning to modify the rosin based on its molecule structure and active group, to develop some deep processing products, and to endure with rosin new characteristic[1]. This work uses the rosin and acrylic acid to form rosin adduct, and then reacted with 2-hydroxyethyl methacrylate (HEMA) to form ester under the different condition. The effect of different ratios with the ...

In situ Synthesis of Rosin Derived Chiral Derivatizing Agents for 31p NMR Assays of Amine and Alcohol Enantiomers

Chiral alcohols（3, 5） were synthesized in optically pure forms from easily available rosin acid in short-steps. A comprehensive protocol for the enantiomeric excess assays of mono- or di-functional-grouped chiral secondary amine or alcohol has been established with them used as chiral auxiliary for chiral phosphorus derivatizing agents（CPDAs） in 3Jp NMR tests. Chemical shift difference（△δp） values ranging from 4.5 to 0.15 between two dias- tereoisomers of the CPDAs and the aryl substrates were obtained. Positive △δR-S was observed for all the tested alco- hol P（III） and P（V） derivatives, while negative △δR-S was observed for all the amines.

Rosin side chain type catalyst-free vitrimers with high cross-link density,mechanical strength,and thermal stability

The emergence of vitrimer,a new class of polymer materials can address the problem of recyclability,reprocess ability and recyclability of thermosetting plastics.Rosin,a natural product,is an ideal raw material for the preparation of polymers in a more sustainable way.Nevertheless,due to the huge steric hindrance caused by the hydrogenated phenanthrene ring structure,the cross-link density of materials is frequently lowered.In this study,hydrogenated rosin was adopted for preparing hydrogenated rosin side-chain type diacids,which were reacted with mixed epoxy to obtain rosin side-chain type vitrimers.It was completely characterized by differential scanning calorimetry test,thermogravimetric analysis,shape memory test and self-healing test.The prepared vitrimers exhibited good self-healing properties,excellent heat resistance(T_(d)=352℃)as well as high mechanical properties(tensile strength of 46.75 MPa).The tricyclic diterpene structure of rosin was introduced into the side chain in order to avoid the reduction of cross-link density resulting from the huge steric hindrance of the rigid tricyclic hydrophenylene skeleton.Vitrimers can undergo dynamic transesterification reaction without external catalysts due to the autocatalytic effect of tertiary amines from epoxy.Moreover,our work expanded the application field of rosin,increased the added value of rosin,and provided a novel method for preparing rosin-based vitrimers with ideal properties.