167 resultados para PHA, BIOPLASTICA, DOWNSTREAM, NaOH
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A new-style silica planar lightwave circuit (PLC) hybrid integrated triplexer, which can demultiplex 1490-nm download data and 1550-nm download analog signals, as well as transmit 1310-nm upload data, is presented. It combines SiO2 arrayed waveguide gratings (AWGs) with integrated photodetectors (PDs) and a high performance laser diode (LD). The SiO2 AWGs realize the three-wavelength coarse wavelength-division multiplexing (CWDM). The crosstalk is less than 40 dB between the 1490- and 1550-nm channels, and less than 45 dB between 1310- and 1490- or 1550-nm channels. For the static performances of the integrated triplexer, its upload output power is 0.4 mW, and the download output photo-generated current is 76 A. In the small-signal measurement, the upstream 3-dB bandwidth of the triplexer is 4 GHz, while the downstream 3-dB bandwidths of both the analog and digital sections reach 1.9 GHz.
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在借鉴国内外现有主要烟气脱硫技术优点的基础上,该研究提出了一种应用多组分粒子流化床(MSFB)的半湿式烟气脱硫技术.在常温下,该研究探讨了MSFB的各种粒子的流态化特性,还进一步研究了多种粒子混合条件下流态化的机理,明确了MSFB正常操作的区域.通过合理的简化与理论上的解析,该研究对MSFB上段自由空间内液滴的传热问题进行了分析,认为MSFB烟气脱硫装置中,液滴下落过程的温度变化极微,可以忽略不计.通过热力学关系的分析,该文提出了MSFB烟气脱硫系统正常稳定操作应遵循的条件,并研究了实验过程中死床现象出现的原因.在250℃进口烟温下,该文通过一系列的实验,研究了MSFB中密相床内浆液的干燥机理.在150℃ˉ250℃较低温度范围内,该文实施了利用Ca(OH)<,2>脱硫剂浆液的模拟烟气脱硫试验,脱硫效率可达95%以上.该文还介绍了该技术的工业示范情况,比较系统地总结了在实际应用中MSFB所遇到的问题及相应采取的解决方案.对MSFB应用于工业实践的具体案例,该文通过细致的技术经济分析,以及与应用NaOH废液时的经济性的比较分析,证明了MSFB半湿式烟气脱硫的良好的技术经济性能.
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The objective of this paper is to investigate the effects of channel surface wettability and temperature gradients on the boiling flow pattern in a single microchannel. The test section consists of a bottom silicon substrate bonded with a top glass cover. Three consecutive parts of an inlet fluid plenum, a central microchannel and an outlet fluid plenum were etched in the silicon substrate. The central microchannel had a width of 800 mu m and a depth of 30 mu m. Acetone liquid was used as the working fluid. High outlet vapor qualities were dealt with here. The flow pattern consists of a fluid triangle (shrinkage of the liquid films) and a connected long liquid rivulet, which is generated in the central microchannel in the timescale of milliseconds. The peculiar flow pattern is formed due to the following reasons: (1) the liquid rivulet tends to have a large contact area with the top hydrophilic channel surface of the glass cover, but a smaller contact area with the bottom silicon hydrophobic surface. (2) The temperature gradient in the chip width direction at the top channel surface of the glass cover not only causes the shrinkage of the liquid films in the central microchannel upstream, but also attracts the liquid rivulet populated near the microchannel centerline. (3) The zigzag pattern is formed due to the competition between the evaporation momentum forces at the vapor-liquid interfaces and the force due to the Marangoni effect. The former causes the rivulet to deviate from the channel centerline and the latter draws the rivulet toward the channel centerline. (4) The temperature gradient along the flow direction in the central microchannel downstream causes the breakup of the rivulet to form isolated droplets there. (5) Liquid stripes inside the upstream fluid triangle were caused by the small capillary number of the liquid film, at which the large surface tension force relative to the viscous force tends to populate the liquid film locally on the top glass cover surface.
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Multi-channel effect is important to understand transport phenomenon in phase change systems with parallel channels. In this paper, visualization studies were performed to study the multi-channel effect in a silicon triple-channel condenser with an aspect ratio of 0.04. Saturated water vapor was pumped into the microcondenser, which was horizontally positioned. The condenser was cooled by the air natural convention heat transfer in the air environment. Flow patterns are either the annular flow at high inlet vapor pressures, or a quasi-stable elongated bubble at the microchannel upstream followed by a detaching or detached miniature bubble at smaller inlet vapor pressures. The downstream miniature bubble was detached from the elongated bubble tip induced by the maximum Weber number there. It is observed that either a single vapor thread or dual vapor threads are at the front of the elongated bubble. A miniature bubble is fully formed by breaking up the vapor thread or threads. The transient vapor thread formation and breakup process is exactly symmetry against the centerline of the center channel. In side channels, the Marangoni effect induced by the small temperature variation over the channel width direction causes the vapor thread formation and breakup process deviating from the side channel centerline and approaching the center channel. The Marangoni effect further forces the detached bubble to rotate and approach the center channel, because the center channel always has higher temperatures, indicating the multi-channel effect.
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Granules of waste tires were pyrolyzed tinder vacuum (3.5-10 kPa) conditions, and the effects of temperature and basic additives (Na2CO3, NaOH) on the properties of pyrolysis were thoroughly investigated. It was obvious that with or without basic additives, pyrolysis oil yield increased gradually to a maximum and subsequently decreased with a temperature increase from 450 degrees C to 600 degrees C, irrespective of the addition of basic additives to the reactor. The addition of NaOH facilitated pyrolysis dramatically, as a maximal pyrolysis oil yield of about 48 wt% was achieved at 550 degrees C without the addition of basic additives, while a maximal pyrolysis oil yield of about 50 wt% was achieved at 480 degrees C by adding 3 wt% (w/w, powder/waste tire granules) of NaOH powder. The composition analysis of pyrolytic naphtha (i.b.p. (initial boiling point) similar to 205 degrees C) distilled from pyrolysis oil showed that more dl-limonene was obtained with basic additives and the maximal content of dl-limonene in pyrolysis oil was 12.39 wt% which is a valuable and widely-used fine chemical. However, no improvement in pyrolysis was observed with Na2CO3 addition. Pyrolysis gas was mainly composed of H-2, CO, CH4, CO2, C2H4 and C2H6. Pyrolytic char had a surface area comparable to commercial carbon black, but its proportion of ash (above 11.5 wt%) was much higher.
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Condensation of steam in a single microchannel, silicon test section was investigated visually at low flow rates. The microchannel was rectangular in cross-section with a depth of 30 pm, a width of 800 mu m and a length of 5.0 mm, covered with a Pyrex glass to allow for visualization of the bubble formation process. By varying the cooling rate during condensation of the saturated water vapor, it was possible to control the shape, size and frequency of the bubbles formed. At low cooling rates using only natural air convection from the ambient environment, the flow pattern in the microchannel consisted of a nearly stable elongated bubble attached upstream (near the inlet) that pinched off into a train of elliptical bubbles downstream of the elongated bubble. It was observed that these elliptical bubbles were emitted periodically from the tip of the elongated bubble at a high frequency, with smaller size than the channel width. The shape of the emitted bubbles underwent modifications shortly after their generation until finally becoming a stable vertical ellipse, maintaining its shape and size as it flowed downstream at a constant speed. These periodically emitted elliptical bubbles thus formed an ordered bubble sequence (train). At higher cooling rates using chilled water in a copper heat sink attached to the test section, the bubble formation frequency increased significantly while the bubble size decreased, all the while forming a perfect bubble train flowing downstream of the microchannel. The emitted bubbles in this case immediately formed into a circular shape without any further modification after their separation from the elongated bubble upstream. The present study suggests that a method for controlling the size and generation frequency of microbubbles could be so developed, which may be of interest for microfluidic applications. The breakup of the elongated bubble is caused by the large Weber number at the tip of the elongated bubble induced by the maximum vapor velocity at the centerline of the microchannel inside the elongated bubble and the smaller surface tension force of water at the tip of the elongated bubble.
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The steady two-dimensional Navier-Stokes equations with the slip wall boundary conditions were used to simulate the supersonic flow in micro convergent-divergent nozzles. It is observed that shock waves can take place inside or outside of the micronozzles under the earth environment. For the over-expanded flows, there is a boundary layer separation point, downstream of which a wave interface separates the viscous boundary layer with back air flow and the inviscid core flow. The oblique shock wave is followed by the bow shock and shock diamond. The viscous boundary layer thickness relative to the whole nozzle width on the exit plane is increased but attains the maximum value around of 0.5 and oscillates against this value with the continuous increasing of the nozzle upstream pressures. The viscous effect either changes the normal shock waves outside of the nozzle for the inviscid flow to the oblique shock waves inside the nozzle, or transfers the expansion jet flow without shock waves for the inviscid flow to the oblique shock waves outside of the nozzle.
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Solid acid 40SiO(2)/TiO2-SO42- and solid base 30K(2)CO(3)/Al2O3-NaOH were prepared and compared with catalytic esterification activity according to the model reaction. Upgrading bio-oil by solid acid and solid base catalysts in the conditioned experiment was investigated, in which dynamic viscosities of bio-oil was lowered markedly, although 8 months of aging did not show much viscosity to improve its fluidity and enhance its stability positively. Even the dehydration by 3A molecular sieve still kept the fluidity well. The density of upgraded bio-oil was reduced from 1.24 to 0.96 kg/m(3), and the gross calorific value increased by 50.7 and 51.8%, respectively. The acidity of upgraded bio-oil was alleviated by the solid base catalyst but intensified by the solid acid catalyst for its strong acidification. The results of gas chromatography-mass spectrometry analysis showed that the ester reaction in the bio-oil was promoted by both solid acid and solid base catalysts and that the solid acid catalyst converted volatile and nonvolatile organic acids into esters and raised their amount by 20-fold. Besides the catalytic esterification, the solid acid catalyst carried out the carbonyl addition of alcohol to acetals. Some components of bio-oil undertook the isomerization over the solid base catalyst.
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A promising application for biomass is liquid fuel synthesis, such as methanol or dimethyl ether (DME). Previous studies have studied syngas production from biomass-derived char, oil and gas. This study intends to explore the technology of syngas production from direct biomass gasification, which may be more economically viable. The ratio of H-2/CO is an important factor that affects the performance of this process. In this study, the characteristics of biomass gasification gas, such as H-2/CO and tar yield, as well as its potential for liquid fuel synthesis is explored. A fluidized bed gasifier and a downstream fixed bed are employed as the reactors. Two kinds of catalysts: dolomite and nickel based catalyst are applied, and they are used in the fluidized bed and fixed bed, respectively. The gasifying agent used is an air-steam mixture. The main variables studied are temperature and weight hourly space velocity in the fixed bed reactor. Over the ranges of operating conditions examined, the maximum H-2 content reaches 52.47 vol%, while the ratio of H-2/CO varies between 1.87 and 4.45. The results indicate that an appropriate temperature (750 degrees C for the current study) and more catalyst are favorable for getting a higher H-2/CO ratio. Using a simple first order kinetic model for the overall tar removal reaction, the apparent activation energies and pre-exponential factors are obtained for nickel based catalysts. The results indicate that biomass gasification gas has great potential for liquid fuel synthesis after further processing.
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The novel hexagon SnO2 nanosheets are successfully synthesized in ethanol/water solution by hydrothermal process. The samples are characterized by X-ray diffraction (XRD), infrared ray (IR) and transmission electron microscopy (TEM). By changing the reaction conditions, the size and the morphology can be controlled. Comparison experiments show that when the temperature increased from 140 degrees C to 180 degrees C, the edge length of the hexagon nanoparticles increases from 300-450 nm to 700-900 nm. On the other hand, by adjusting the ratios of water to ethanol from 2 to 0.5, SnO2 nanoparticles with different morphologies of triangle and sphere are obtained. When the concentration of NaOH is increased from 0.15 M to 0.30 M, a hollow ring structure can be obtained. (c) 2006 Elsevier B.V. All rights reserved.
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研究生物法提取桑皮纤维的最佳漂白工艺。【方法】采用回归正交组合设计,研究了碱(NaOH)用量、漂白剂(H2O2)用量、水料比、漂白温度及漂白时间对生物法提取桑皮纤维漂白的技术参数。【结果】(1)各因子对纤维白度的影响程度依次为:漂白温度>漂白时间>碱用量>漂白剂用量>水料比,漂白温度是漂白过程中的关键控制因素。(2)因子交互效应分析显示,碱用量与漂白温度、漂白剂用量与漂白时间、料水比与漂白时间通过互作产生了增白效应。【结论】通过对纤维白度模型的优化,得到的最佳漂白工艺参数为:碱用量2.05 g/L,漂白剂用量6%,水料比16.7∶1,漂白温度112℃,漂白时间125 min。在最佳工艺参数条件下,纤维白度可达75.0以上,经反复试验验证,该工艺正确可行。
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以黄土高原自北向南采集的12个0~20 cm耕层土壤为供试土样,采用Tiessen和Moir修正的Hedley土壤有机无机磷分级方法研究了黄土高原石灰性土壤中不同形态磷组分的分布特征。结果表明:供试土壤各形态P总体分布特征为:HCl-P>Residual-P>NaHCO3-Po>NaHCO3-Pi>NaOH-Po>NaOH-Pi>H2O-P,以HCl-P和Residual-P为主,分别占土壤全磷的54.00%~88.96%和0~39.11%。黄土高原土壤磷含量总体分布表现为南高北低。在各土壤类型间,NaOH-Po、Residual-P和全磷平均含量表现为干润砂质新成土<黄土正常新成土<简育干润均腐土<土垫旱耕人为土,自北向南依次增加;H2O-P和HCl-P表现为简育干润均腐土<黄土正常新成土<干润砂质新成土<土垫旱耕人为土,自北向南先降后升,且上升幅度较大。黄土高原土壤全氮与全磷及各形态磷含量相关性均达显著水平,其中与NaOH-Pi、NaOH-Po、HCl-P及全磷含量达到极显著水平。C/N、pH及砂粒与全磷及各形态磷含量呈负相关关系,其中pH与NaHCO3-Po呈显著负相关,与H2O-P、NaHCO3-Pi...
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采用水热法结合后续热处理制备了一系列纯的和稀土离子(Eu3+,Dy3+)掺杂的黔具有纳米/微米结构的无机氧化物材料,包括YB03、姚03、Ga203和硅基MCM一攀41介孔分子筛体系。研究了这些体系的水热产物的晶体形貌、结构以及它们的生乖~一_长机理,并通过进一步热处理得到了保持水热产物纳米/微米结构形貌的发光材料,报道了以上各个体系材料的光致发光性能。一把姚03和Eu203粉末直接加入H3Bo3水溶液中,调节pH一1一4,在180一270夸_少℃水热处理得到了具有vaterite结构的YBo3:Eu3+晶体。xRD和FEsEM结果证明一扭03:E矿"晶体是由厚度小于50nm的纳米晶片构成的花状和猴头菇状的微米级晶丫体。水热温度提高时纳米晶片的厚度没有增加,形貌也不变,但是结晶度和发光一强度有所提高。pH值对纳米晶片之间的距离、角度和晶片数量有影响。pH低时,纳米晶片更多且包裹得更紧,形成了猴头菇状;而pH高时,晶片分得更开一些呈花朵状。这与pH值低时结晶成核较快较多有关。YB03:E矿+水热和固相法样品在24Onm激发下的发光谱峰位相同。但水热样品比固相法样品具有较高的红橙比[Eu3+:I(,D。一7F2)/I(SD。一7FI)],增加了12一37%。在24oC下制备的花03:Eu3+水热样品具有最大的结晶度和发光强度。报道了三种晶形调节剂对水热晶体形貌的影响结果。硝酸钻水溶液用氨水调节至pH一8一n,200oC下水热处理24小时,产物经xRD确定是单斜晶系的碱式硝酸盐叽O(0H)9困03)。FEsEM观察发现产物是一种具有几_三叶形截面的棱柱。改变合成条件可以调节三叶形棱柱的尺寸。增加氨水量时,PH从8调到n后,棱柱直径可从微米级调节到亚微米级,即从3一5林m左右下降到200一300纳米,同时长径比也有所增加,从pH一8的5增加到pH=n的10。调节机制可解释为较高的pH条件下结晶成核作用进行较快,形成了更多的晶核。三叶形棱柱的生长机理是、O(OH)9困03)的晶核依靠内在的趋势长成棒状纳米粒子;并通过一种直接的聚集生长,这些起始的纳米棒沿着它们横截面的径向方向快速自堆积成一种Y型结构的棒束;然后沿着棱柱轴向和平行于棱柱叶片方向的晶面同时优先生长,而垂直于叶片方向上的晶面生长得相对缓慢,导致三叶形棱I、-纳米/微米结构氧化物材料的水热合成、形貌与发光性质研究柱的形成。、经过高温相转变得到了姚03三叶形棱柱。采用同样方法可以制得姚03:E矿+的三叶形棱柱发光粉,其光谱与固相法样品的一致。将Gacl3一HZO一NaOH体系在pH=6一8时于180℃下水热处理得到了正交晶系的Gao0H晶体,其形貌分别是宽度在200一30Onm之间长径比约1:7的四方棱柱(pH=6)和长径比约1:3纺锤状的纳米棒束(pH=8)。使用HZO/DEG混合溶剂可以增加棱柱的长径比,1:Ivol时增加到1:15;1:Zvol时获得的是长达几十微米的四方棱柱纳米线6Go0OH纳米棒是从最初的胶状沉淀中成核后沿着c轴优先生长而成的。pH值的高低可导致Ga0OH晶体从四方棱柱到纳米棒束的不同形貌。DEG的存在对晶体的生长可能有两点作用:一是抑制晶核形成;二是降低晶体沿着横截面晶面的生长速度。经过高温锻烧的产物是保持着前驱体形貌的p一GaZO3晶体。254nm激发下p一GaZO3纳米棒的发射谱是从300nm到600nln的宽峰,最大值在455nln。发光的平均寿命是64ns。其蓝光发射起源于氧空位给体提供的电子和来自受体嫁空位或者嫁氧空位对的空穴之间的复合。采用相似方法制备了p一GaZO3:Dy纳米棒束,并与固相法样品对比了光谱性质的异同。将三种5102基材料:MCM一41型分子筛(直接分子筛CMS和萃取分子筛EMS)、无规颗粒(ASP)和干凝胶(SG)进行从室温到1000℃的不同温度不同时间热处理。254nm激发下,MCM一41没有发光现象。而ASP和SG系列样品随着热处理温度不同而显示不同的PL。说明ASP和SG与MCM一41有着不同的发光机理。排除了ASP和SG样品的发光中心是来自5102网络本身的结构缺陷,认为是其中所含有机物在热处理中产生的碳杂质引起。结果也表明MCM41中模板剂在热处理的碳化产物并没有引起MCM一41的PL。在365nm激发下,MCM一41与ASP、SG的PL现象大致相同。表明所有系列的样品的发光机理相同。CMS和EMS两个系列在300℃以上处理的样品的PL相似,说明模板剂的存在及其碳化并没有影响MCM一41的PL。所有系列样品在365nm激发下的PL认为是起源于5102网络中与氧相关的结构缺陷三Si一0.,而不是碳掺杂作用引起的。
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Ⅰ. 聚合过程中聚合物交联反应机制的探讨 聚丙烯酰胺是水溶性聚合物,但一般工业生产的聚丙烯酰胺在水中很难溶解。一个重要因素是由于在聚合过程中聚合物发生了交联。Minsk (1949)认为聚丙烯酰胺大分子上的-CoNH_2的亚胺化,导致聚合物在水中难溶或不溶:Gleason (1959)和Suen (1960)分别指出活性链的链转移和在丙烯酰胺聚合过程中产生末端双键是聚合物交联的起因:AδkuH (1973)认为丙烯酰胺在浓水溶液中聚合是通过水离子作用生成网状聚合物。由于交联是一个伴随聚合的付反应,少量的交联就导致聚合物不溶,加之缺乏有效的分析手段,所以难于定量研究这一过程。一些科学工作者对交联的性质提出了各种设想,但有关交联方面的系统讨论加交联机制问题至今未见报导。本工作估算了聚丙烯酰胺的内聚能和分子间力(主要-CoNH_2间氢键作用力),说明了丙烯酰胺浓度越大,它的聚合产物越易交联;研究了聚合体系PH值对聚合交联的影响,丙烯酰胺在酸性或中性介质中用r射线引发聚合,很快出现凝胶,只有在碱性(PH > 13)介质中r射线幅照可得到水溶性聚丙烯酰胺。用酰胺基的亲核反应能力解释了原子效应,幅照生成聚合物自由基和双键是聚合物交联的潜在因素,在聚合体系加入链转移剂抗坏血酸,可有效地抑制聚合过程中聚合物的迅速交联;从红外光谱观察到交联聚丙烯酰胺的酰胺特征吸收峰从1650 cm~(-1)向亚胺特征吸收峰方向位移,聚丙烯酰胺的含N量低于理论值,交联聚丙烯酰胺含N量偏离理论值更大,以及不溶聚丙烯酰胺的交联键可以羟高温水解完全破坏,由此肯定聚合过程中聚合物交联具有亚胺结构。根据酰胺基结构特点加亲核取代反应原理,提出丙烯酰胺水溶液辐射聚合过程中聚合物的交联机制如下:1.聚合物自由基的生成。2.自由基促使-CoNH_2活化,导致-CoNH_2间亲核取代反应。3.当R_2 = -CH=CH_2即单体参与亚胺化则导致在分子链上产生悬挂双键,将引起聚合物交联。这一反应机制可以阐明丙烯酰胺水溶液辐射聚合过程中聚合交联起因和历程,可以解释键材剂。质子效应和亚胺之间联系,为制备水溶性聚丙烯酰胺提供了线索。Ⅱ. 聚丙烯酰胺的溶解 关于聚合物溶解理论前人曾从两方面进行探讨。一是Hidebrand (1949)提出以内聚能密度的平方根作为溶度参数δ来鉴别两种物互溶的可能性。Burrel (1955)把这一方法来研究聚合物的溶解。内聚能依赖于色散力、极性力和氢/键,它由三部分组成E = E_d + E_p + E_h,对应的溶度参数方程为δ~2 = δ_d~2 + δ_p~2 + δ_h~2,因此只有两种物质的溶度参数的各个分量相近时,才有可能互溶。这一方面的研究仅涉及溶解过程的热力学。另一是Ueberreiter (1968)提出溶解是一个相互扩散过程。聚合物在溶解过程中,溶解速度S和溶胀层厚度δ处于稳态。它们和溶剂在聚合物中平均扩散系数D-bar_s的关系为2S = D-bar_s/δ,比式直接反映了溶解的动力学过程。聚丙烯酰胺有极强的极性和形成氢键的能力,它只溶于水,对溶度参数的研究存在一定困难。采用扩散原理研究聚丙烯酰按的溶解速度和规律比较有利。为此目地,我们设计制作了专门溶解实验装置,借助聚丙烯酰胺存在电离基因,利用电导测定溶解速度S,并借助针入法则定溶胀层厚度δ和溶胀速度W,发现极性聚丙烯酰胺的溶解不同于Ueberreiter所研究的非极性聚合物聚苯乙烯的溶解。它是一个非稳态过程,不存在诱导期,溶解和溶胀同时进行,根据这事实和理论分析得到2S + W = (D-bar)_s/δ这一关系式与实验数据相符。此关系式可还原Ueberreinter的稳态溶解得到的关系式,并适用于交联聚合物的溶胀。聚丙烯酰胺的-CoNH_2强吸水性导致它在溶解时溶胀形成凝胶层是一个快步骤,而-CoNH_2强的形成氢键能A是溶解的主要障碍,因此溶解是一个慢过程。聚丙烯酰胺的溶解活化能E_s和水在聚合物中扩散活化能E_D都是6干卡/克分子左右;处于氢键离解能范围之内,所以聚丙烯酰胺溶解主要克服分子间氢键作用力。研究了影响聚丙烯酰胺的溶解因素:(1)聚丙烯酰胺单位时间溶解量与它们的颗粒直径2.5次方成反比。(2)聚丙烯酰胺溶解速度与分子量0.5 - 0.7次方成反比。(3)聚丙烯酰胺溶解速度对湿度的依赖关系为S = 0.278 exp[-627o/RT](4)聚丙烯酰胺大分子中引进-CooNa,吸水性增强,溶解过程双电层形成,产生剪切应力和静电斥力,促使键移动,降低了溶解活化能,加速溶解。(5)聚合物中添加亲水性强的表面活活性剂有利于聚丙烯酰胺的溶解。Ⅲ. 合成在水中易溶或速溶丙烯酰胺聚合物和共聚物 本文强调了在丙烯酰胺水溶液辐射聚合过程中,避免聚合物交联是合成水溶性聚合物的先决条件。加NaOH的丙烯酰胺水溶液聚合和加链转移剂抗坏血酸的丙烯酰胺水溶液聚合物都可得到转化率和分子量都较高,而且不交联的丙烯酰胺的聚合物和共聚物。在单体水溶液中添加尿素对聚合物有助溶效果;添加亲水性强的表面活性剂JFC可改善聚合物颗粒的粘结和抱团。提出了两个聚合体系,合成出在水中速溶的聚丙烯酰胺和羰钠基不同含量的阴离子型 聚丙烯酰胺,聚合物颗粒小于40目,可在10分钟内完成溶解。