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Oxidation of Partially Hydrolyzed Polyacrylamide from Polymer Flooding Processes Using Fenton Reagents 被引量:1
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作者 Li Jinlian Wang Jia +2 位作者 Liu Hongyan Wu HongJun Zhang Yongjun 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS CSCD 2023年第4期86-92,共7页
The degradation of partially hydrolyzed polyacrylamide(HPAM) found in alkaline/surfactant/polymer flooding sewage was investigated using Fenton-type reagents. Different Fenton reagent treatments for HPAM degradation w... The degradation of partially hydrolyzed polyacrylamide(HPAM) found in alkaline/surfactant/polymer flooding sewage was investigated using Fenton-type reagents. Different Fenton reagent treatments for HPAM degradation were compared. The effects of pH, hydrogen peroxide(H_(2)O_(2)), ferrous ion(Fe^(2+)), and tartaric ion(C_(4)H_(4)O_(6)^(2-)) concentrations were studied. The degradation reaction occurred within a wide range of pH(3–9). The HPAM degradation performance of photo-Fenton processes using solar light and UV were compared with that of the Fenton process. The degradation rate was found to be strongly dependent on the H_(2)O_(2)/Fe^(2+)/C_(4)H_(4)O_(6)^(2-)molar ratio. The HPAM degradation efficiency was 90%, and the chemical oxygen demand removal efficiency was 85%. HPAM could be degraded into a compound with a lower molecular weight, but it was difficult to achieve complete mineralization to CO_(2). The presence of intermediate products hindered further oxidation in the Fenton process. 展开更多
关键词 PHOTODEGRADATION UV Fenton reagent partially hydrolyzed polyacrylamide
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A review of complications of polyacrylamide hydrogel injection 被引量:1
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作者 Chenlu Xiong Youbai Chen +7 位作者 Yujian Xu Weiqian Jiang Xiangye Yin Dongsheng Chen Xiaojing Gong Tian He Yang An Yan Han 《Chinese Journal of Plastic and Reconstructive Surgery》 2023年第2期86-95,共10页
Once a popular injectable filler,polyacrylamide hydrogel(PAAG)has been banned in China since 2006 due to its unclear safety and long-term complications.However,it is still being used worldwide because of its huge comm... Once a popular injectable filler,polyacrylamide hydrogel(PAAG)has been banned in China since 2006 due to its unclear safety and long-term complications.However,it is still being used worldwide because of its huge commercial profit,leading to emerging complications and an urgent need for standardized clinical management.This review aimed to assess the properties,safety,and complications of PAAG and treatment strategies for its removal. 展开更多
关键词 polyacrylamide hydrogel FILLERS COMPLICATIONS TREATMENT REMOVAL
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Synthesis and Flocculation of Polyacrylamide with Low Water Absorption for Non-dispersible Underwater Concrete
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作者 LI Hongling YAN Na +2 位作者 SUN Guowen ZHENG Haorui YANG Xinyu 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2023年第6期1404-1413,共10页
The polyacrylamide which is directly added into concrete shows strong water absorption property.Thus the construction of underwater constructure would demand high amount of water,resulting in poor workability of concr... The polyacrylamide which is directly added into concrete shows strong water absorption property.Thus the construction of underwater constructure would demand high amount of water,resulting in poor workability of concrete and strength shrinkage after hardening.Herein,a kind of anionic polyacrylamide(APAM)grafted with water reducing functional group(-COOH)was synthesized at low temperatures by partial factor design and response surface design.The structure and morphology of APAM were characterized by UV,FTIR and SEM methods.The experimental results show that the molecular weight of the synthesized APAM could reach 11 million,under the condition that the temperature was 35℃,the pH value was 8,the monomer concentration was 27wt%,the initiator dosage was 0.6wt%,and the monomer ratio(n(AM):n(AA))was 3.When the APAM was applied into the underwater slurry,it presented good flocculation and low water demand.When the dosage was 1%of the mass of the cement,the water demand increased by 12%,which could meet the self-leveling and anti-dispersity of the underwater slurry at the same time.This technology provides technical guidance for the large-scale industrial production of polyacrylamide for underwater concrete construction while achieving environmental protection during production. 展开更多
关键词 non-dispersible underwater concrete anionic polyacrylamide partial factor design response surfacedesign FLOCCULATION
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Study on the Effects of Polyacrylamide on Phosphorus Adsorption and Desorption Characteristics of Soil Aggregates 被引量:7
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作者 杨雪芹 王旭东 《Agricultural Science & Technology》 CAS 2008年第3期149-152,共4页
[Objective]The research aimed to provide scientific reference for reasonable utilization of polyacrylamide(PAM).[Method]After PAM treatment,the soil aggregates were classified through dry sieve analysis and the adsorp... [Objective]The research aimed to provide scientific reference for reasonable utilization of polyacrylamide(PAM).[Method]After PAM treatment,the soil aggregates were classified through dry sieve analysis and the adsorption capacity and desorption capacity of all soil aggregates to phosphorus at different phosphorus concentrations were analyzed.[Result] The phosphorus adsorption and desorption of soil sample treated by PAM declined. The amount of phosphorus adsorption increased with the increase of phosphorus concentration and this increase was fast in low phosphorus concentration area but slow in high phosphorus concentration area.At different phosphorus concentrations,adsorption showed a へ shape changing trend.The phosphorus adsorption was related to phosphorus concentration and the 2-3 mm aggregate had the highest desorption rate while 0.1-0.25 mm aggregate and 0.45-1 mm aggregate had lowest desorption rate.[Conclusion]The PAM treatment generated significant influence on phosphorus adsorption and analytic features of aggregate in all size fractions. 展开更多
关键词 Lou soil polyacrylamide(PAM) AGGREGATE PHOSPHORUS ADSORPTION DESORPTION
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Optimization of SSR-PCR Non-denatured Polyacrylamide Gel Electrophoresis Conditions in Kernelled Apricot 被引量:1
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作者 艾鹏飞 方闪闪 +1 位作者 吴学敏 靳占忠 《Agricultural Science & Technology》 CAS 2010年第9期50-52,139,共4页
[Objective] The aim was to optimize the SSR-PCR non-denatured polyacrylamide gel electrophoresis conditions in kernelled apricot.[Method]25 accessions of kernelled apricot and three accessions of edible apricot were s... [Objective] The aim was to optimize the SSR-PCR non-denatured polyacrylamide gel electrophoresis conditions in kernelled apricot.[Method]25 accessions of kernelled apricot and three accessions of edible apricot were selected as experimental materials to screen the repeatable SSR loci with high polymorphism by the use of SSR markers combined with non-denatured polyacrylamide gel electrophoresis.And the effect of different factors on electrophoresis conditions was compared to explore the optimal SSR-PCR non-denatured polyacrylamide gel electrophoresis conditions in kernelled apricot.[Result]The optimal non-denatured polyacrylamide gel electrophoresis conditions for SSR-PCR were established as follows:polyacrylamide gel concentration 6%,the ratio of acrylamide to bisacrylamide 29∶1,electrophoresis at 1 000 V for 2-3 h,and staining for 15 min within 0.1% AgNO3.[Conclusion]The optimum electrophoresis system has provided some technical foundations to further study the phylogenetic relationship of kernelled apricots by SSR markers. 展开更多
关键词 Kernelled Apricot SSR markers polyacrylamide gel electrophoresis Silver staining
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Improvement of Polyacrylamide Gel Electrophorus in Phytophthora infeatans SSR Marker 被引量:1
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作者 张芳 权军利 单卫星 《Plant Diseases and Pests》 CAS 2011年第4期3-5,共3页
[Objective] The paper was to improve polyacrylamide gel electrophorus in Phytophthora infeatans SSR Marker.[Method] With the disease sample of P.infeatans collected from Guyuan in Ningxia Province in 2009 as test mate... [Objective] The paper was to improve polyacrylamide gel electrophorus in Phytophthora infeatans SSR Marker.[Method] With the disease sample of P.infeatans collected from Guyuan in Ningxia Province in 2009 as test material,its DNA was extracted and amplified with PCR,and its products were carried out polyacrylamide gel electrophoresis.[Result] 12% polyacrylamide gel electrophoresis was used to detect primers D13,G11 and PI02,and 8% polyacrylamide gel electrophoresis was used to detect primers PI4B,PI63,SSR4,SSR8 and SSR11,then 0.1% silver nitrate was used to stain,and an ideal electrophoresis and staining effect was obtained.[Conclusion] The electrophoresis and staining method suitable for P.infeatans SSR Marker established in the study had the characteristics of high sensitivity,simple operation and clear bands,which was an effective,simple and quick detection method. 展开更多
关键词 polyacrylamide gel electrophorus Phytophthora infestans SSR China
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EXPERIMENTAL CHARACTERIZATION OF FLUOROCARBON-MODIFIED POLYACRYLAMIDE/SURFACTANT AQUEOUS SOLUTIONS
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作者 杨振忠 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2003年第3期297-302,共6页
The interaction between surfactants and fluorocarbon-modified polyacrylamide (FC-PAM) in aqueous solutionswas evaluated by rheological means and fluorescence spectroscopy and was found to be strong regardless of the s... The interaction between surfactants and fluorocarbon-modified polyacrylamide (FC-PAM) in aqueous solutionswas evaluated by rheological means and fluorescence spectroscopy and was found to be strong regardless of the surfactant'snature. Two representative surfactants, anionic sodium dodecyl sulfate (SDS) and nonionic Triton X-100, were used. The origin of the interaction and its dependence on the surfactant concentration were discussed. 展开更多
关键词 polyacrylamide Fluorocarbon-modified polyacrylamide SURFACTANT Rheology Fluorescence Spectroscopy
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Drag reduction behavior of hydrolyzed polyacrylamide/xanthan gum mixed polymer solutions 被引量:9
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作者 Mehdi Habibpour Peter E. Clark 《Petroleum Science》 SCIE CAS CSCD 2017年第2期412-423,共12页
Partially hydrolyzed polyacrylamide(HPAM)as the main component of slickwater fracturing fluid is a shear-sensitive polymer,which suffers from mechanical degradation at turbulent flow rates.Five different concentrati... Partially hydrolyzed polyacrylamide(HPAM)as the main component of slickwater fracturing fluid is a shear-sensitive polymer,which suffers from mechanical degradation at turbulent flow rates.Five different concentrations of HPAM as well as mixtures of polyacrylamide/xanthan gum were prepared to investigate the possibility of improving shear stability of HPAM.Drag reduction(DR)measurements were performed in a closed flow loop.For HPAM solutions,the extent of DR increased from 30%to67%with increasing HPAM concentration from 100 to1000 wppm.All the HPAM solutions suffered from mechanical degradation and loss of DR efficiency over the shearing period.Results indicated that the resistance to shear degradation increased with increasing polymer concentration.DR efficiency of 600 wppm xanthan gum(XG)was 38%,indicating that XG was not as good a drag reducer as HPAM.But with only 6%DR decline,XG solution exhibited a better shear stability compared to HPAM solutions.Mixed HPAM/XG solutions initially exhibited greater DR(40%and 55%)compared to XG,but due to shear degradation,DR%dropped for HPAM/XG solutions.Compared to 200 wppm HPAM solution,addition of XG did not improve the drag reduction efficiency of HPAM/XG mixed solutions though XG slightly improved the resistance against mechanical degradation in HPAM/XG mixed polymer solutions. 展开更多
关键词 Slickwater polyacrylamide Xanthan gum Drag reduction Shear stability
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Study on purification technology of polyacrylamide wastewater by non-thermal plasma 被引量:8
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作者 Junfeng RONG Kaixun ZHU Minggong CHEN 《Plasma Science and Technology》 SCIE EI CAS CSCD 2019年第5期66-72,共7页
In this work, non-thermal plasma has been applied to treat polyacrylamide(PAM) wastewater.We have investigated the influence of the rule of PAM wastewater initial pH, solution concentration and discharge time, disch... In this work, non-thermal plasma has been applied to treat polyacrylamide(PAM) wastewater.We have investigated the influence of the rule of PAM wastewater initial pH, solution concentration and discharge time, discharge voltage on chemical oxygen demand(COD)degradation rate. At the same time, the effect of pH and discharge time on the viscosity removal rate of PAM solution was also studied. Then, the effect of pH on the viscosity removal rate of1.0 gl-1 PAM solution was studied separately. Through orthogonal test, the factors affecting the COD degradation rate of PAM wastewater were determined as follows: discharge time > discharge voltage > solution concentration > wastewater initial pH. The COD highest removal rate of PAM wastewater reached 85.74%, when the optimal conditions are as follows:discharge voltage 40 k V, discharge time 5 h, solution concentration 1.0 gl-1, pH 1.5. This research provides some basic data and new theoretical basis for PAM wastewater purification. 展开更多
关键词 NON-THERMAL plasma polyacrylamide COD degradation RATE VISCOSITY removal RATE DISCHARGE voltage
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Application of Tertiary Amine Cationic Polyacrylamide with High Cationic Degree in Salt-free Dyeing of Reactive Dyes 被引量:9
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作者 TENG Xiaoxu MA Wei ZHANG Shufen 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2010年第6期1023-1028,共6页
Tertiary amine cationic polyacrylamide with high cationization degree was used as a new cationic agent to pretreat cotton with dip-pad-bake method. The obtained cationic cotton was dyed with reactive dyes in the ab-se... Tertiary amine cationic polyacrylamide with high cationization degree was used as a new cationic agent to pretreat cotton with dip-pad-bake method. The obtained cationic cotton was dyed with reactive dyes in the ab-sence of electrolyte. The effects of the characteristics of the cationic agent and the pretreatment conditions on dye-ability of reactive dye were investigated. The results showed that the fixation and K/S values of the reactive dyes on the cationic cotton were improved compared with those on the untreated one in the presence of salt. Tests on fast-ness properties of the dyed cotton and fabric quality of the pretreated cotton were carried out and the results showed that wash and rub fastness of the salt-free dyeing were both satisfactory. And anti-crease property,tensile and tear strength,and handling of the cationic cotton were also good compared with that of the untreated one. 展开更多
关键词 tertiary amine cationic polyacrylamide reactive dye cotton fabric salt-free dyeing
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Dissolution Characteristics of Hydrophobically Associating Polyacrylamide in Stirred Tanks 被引量:7
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作者 周国忠 谢明辉 +3 位作者 刘敏 吴华晓 龙湘犁 虞培清 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2010年第1期170-174,共5页
Enhanced oil recovery(EOR)by means of polymer flooding is an important technology for the strategic development of offshore oilfields in China.Hydrophobically associating polyacrylamide(HAPAM)has been recently propose... Enhanced oil recovery(EOR)by means of polymer flooding is an important technology for the strategic development of offshore oilfields in China.Hydrophobically associating polyacrylamide(HAPAM)has been recently proposed as a new flooding agent.The solubility of HAPAM is low,which is the bottleneck for further improving the oil recovery through polymer flooding in offshore oilfield.Stirred tanks have been used on offshore platforms to enhance HAPAM dissolving.But there is little literature on the study of HAPAM dissolving characteristics in stirred tanks.In this paper,effects of temperature,salinity,stirring speed,impeller type and stirring method on the dissolution of HAPAM are reported.The experimental results manifest that the dissolving rate of HAPAM increases with temperature and stirring speed,but the viscosity of the polymer solution decreases.There is an optimal range of salinity for polymer dissolving.Combining the operation mode of up-pumping with varying stirring speed,hydrofoil impeller can accelerate the dissolution of HAPAM and maintain a high solution viscosity. 展开更多
关键词 hydrophobically associating polyacrylamide VISCOSITY dissolution time impeller type stirring method
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Preparation of cationic polyacrylamide microsphere emulsion and its performance for permeability reduction 被引量:9
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作者 Guo Aijun Geng Yiran +3 位作者 Zhao Lili Li Jun Liu Dong Li Peng 《Petroleum Science》 SCIE CAS CSCD 2014年第3期408-416,共9页
In this paper, cationic polyacrylamide microspheres (CPAM) were synthesized using acrylamide (AM) and methacryloyloxyethyl trimethyl ammonium chloride (TMAEMC) as monomers, ammonium sulfate as dispersant, poly(... In this paper, cationic polyacrylamide microspheres (CPAM) were synthesized using acrylamide (AM) and methacryloyloxyethyl trimethyl ammonium chloride (TMAEMC) as monomers, ammonium sulfate as dispersant, poly(acryloyloxyethyl trimethyl ammonium chloride) (PAETAC) as dispersion stabilizer, and ammonium persulfate as initiator. The synthetic method was dispersion polymerization. The effects of monomer ratio (AM/TMAEMC), dispersant concentration, and dispersion stabilizer dosage on dispersion polymerization were systematically studied to determine the optimal preparation conditions. The structure and viscosity of the synthesized polymer were characterized by FTIR and capillary viscometry, respectively, and the particle sizes and distribution of the polymer microspheres were characterized by microscopy and dynamic light scattering, respectively. Finally, flow tests were conducted to measure the permeability reduction performance of the microspheres at various concentrations in sand packs with different permeability. Results show that CPAM emulsion of a solids content of 1 wt% has excellent performance in low-to-medium permeability formations (〈 1,000 mD), and the efficiency may reach above 90%. 展开更多
关键词 Dispersion polymerization cationic polyacrylamide microspheres profile modification permeability reduction
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Rheological Properties of Hydrophobically Associating Polyacrylamide Solution 被引量:5
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作者 Ren Kun Wang Jinlan +1 位作者 Lin Meiqin Xu Chunming 《Petroleum Science》 SCIE CAS CSCD 2006年第2期66-72,共7页
A temperature-resistant, salt-tolerant polyacrylamide, hydrophobically associating polymer (HAP), was synthesized in the State Key Laboratory of Heavy Oil Processing. The rheological behavior of HAP solution was inv... A temperature-resistant, salt-tolerant polyacrylamide, hydrophobically associating polymer (HAP), was synthesized in the State Key Laboratory of Heavy Oil Processing. The rheological behavior of HAP solution was investigated by means of flow experiments in porous media and by using a HAAKE RS600 rheometer. The results of Nuclepore membrane filtration showed that filtration time increased sharply when the critical association concentration was reached. Shear rate had a greater impact on viscosity and shear stress with increasing HAP concentration. The HAP solution with a concentration of 100 mg/L (salinity 32,868 mg/L) exhibited negative thixotropy. However, at the same salinity the HAP solution showed thixotropy and its viscosity became greater when the polymer concentration increased to 1,500 mg/L. The flow experiments in cemented core samples indicated that the resistance factor and residual resistance factor of the HAP solution were 31.8 and 12 when polymer concentration and salinity were 1,500 mg/L, 32,868 mg/L at 85℃ respectively, which is favorable for flooding application. Such factors of partially hydrolyzed polyaerylamide 3530S were merely 3.14 and 1.71, so it could not be applied to polymer flooding in the oilfield with high temperature and high salinity. 展开更多
关键词 Temperature-resistant salt-tolerant polyacrylamide hydrophobically associating polymer RHEOLOGY porous media VISCOSITY
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MONODISPERSE MICRON-SIZED POLYACRYLAMIDE PARTICLES SYNTHESIZED BY DISPERSION POLYMERIZATION 被引量:6
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作者 侯信 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2007年第3期277-283,共7页
Monodisperse micron-sized polyacrylamide (PAM) particles with a regular shape have been successfully prepared through dispersion polymerization of the monomer using a rotary reactor. FTIR and NMR spectroscopic resul... Monodisperse micron-sized polyacrylamide (PAM) particles with a regular shape have been successfully prepared through dispersion polymerization of the monomer using a rotary reactor. FTIR and NMR spectroscopic results demonstrated the formation of PAM. POM and TEM observations revealed that PAM particles had a regular shape and good dispersity. A thick layer of surfactant (PVP) still existed on PAM particles after multiple centrifugation and ultrasonic re-dispersion in ethanol, which indicates a strong interaction between PVP and PAM. The effects of various polymerization factors on the average size of PAM particles have also been studied. 展开更多
关键词 Dispersion polymerization polyacrylamide Rotary reactor
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Treatment of Wastewater Containing Polyacrylamide Using Three Dimensional Electrodes 被引量:6
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作者 CHEN Wu YANG Changzhui +1 位作者 MEI Ping YIN Xianqing 《Wuhan University Journal of Natural Sciences》 CAS 2007年第2期353-360,共8页
A method using three-dimensional electrode is applied to treat wastewater in oil fields, which contains polyacrylamide (PAM), for analogue. A best condition for electrolysis (I= 1.0 A, t=90 min, c=0.1%, m=980 g,φ=... A method using three-dimensional electrode is applied to treat wastewater in oil fields, which contains polyacrylamide (PAM), for analogue. A best condition for electrolysis (I= 1.0 A, t=90 min, c=0.1%, m=980 g,φ=5 mm, d=5.0 cm) has been determined, under which the COD removal efficiency reached 96.0%, COD containing in wastewater reduced to 64.3 mg/L from 1 622.9 mg/L, the figure before treatment. Three categories of PAM-containing wastewater in production practice have been treated with the COD removal ratios being 87.5%, 82.4% and 84.7% respectively. Presence of H2O2 and ·OH are detected by means of Ti(IV)-5-Br-PADAP technique and colorimetry respectively. The concentration is positively proportional to the COD removal ratio and increases in accordance with increment of time of electrolysis and current. 展开更多
关键词 ELECTROCHEMISTRY three-dimensional electrode (TDE) oilfield wastewater treatment polyacrylamide (PAM)
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Intermittent swelling and shrinkage of a highly expansive soil treated with polyacrylamide 被引量:4
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作者 Amin Soltani An Deng +1 位作者 Abbas Taheri Brendan C.O’Kelly 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2022年第1期252-261,共10页
This laboratory study examines the potential use of an anionic polyacrylamide(PAM)-based material as an environmentally sustainable additive for the stabilization of an expansive soil from South Australia.The experime... This laboratory study examines the potential use of an anionic polyacrylamide(PAM)-based material as an environmentally sustainable additive for the stabilization of an expansive soil from South Australia.The experimental program consisted of consistency limits,sediment volume,compaction and oedometer cyclic swell-shrink tests,performed using distilled water and four different PAM-to-water solutions of P_(D)=0.1 g/L,0.2 g/L,0.4 g/L and 0.6 g/L as the mixing liquids.Overall,the relative swelling and shrinkage strains were found to decrease with increasing number of applied swell-shrink cycles,with an‘elastic equilibrium’condition achieved on the conclusion of four cycles.The propensity for swelling/shrinkage potential reduction(for any given cycle)was found to be in favor of increasing the PAM dosage up to P_(D)=0.2 g/L,beyond which the excess PAM molecules self-associate as aggregates,thereby functioning as a lubricant instead of a flocculant;this critical dosage was termed‘maximum flocculation dosage’(MFD).The MFD assertion was discussed and validated using the consistency limits and sediment volume properties,both exhibiting only marginal variations beyond the identified MFD of P_(D)=0.2 g/L.The accumulated axial strain progressively transitioned from‘expansive’for the unamended soil to an ideal‘neutral’state at the MFD,while higher dosages demonstrated undesirable‘contractive’states. 展开更多
关键词 Expansive soil polyacrylamide(PAM) Consistency limits Sediment volume Swell-shrink cycles Swelling and shrinkage strains Accumulated axial strain
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Synthesis of YAG∶Ce^(3+) Phosphor by Polyacrylamide Gel Method and Promoting Action of α-Al_2O_3 Seed Crystal on Phase Formation 被引量:5
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作者 李永绣 李颖毅 +4 位作者 闵宇霖 吴燕利 程昌明 周雪珍 辜子英 《Journal of Rare Earths》 SCIE EI CAS CSCD 2005年第5期517-520,共4页
YAG: Ce^3 + phosphor particles were prepared using polyacrylamide gel method. The structure evolution of powders during annealing process was followed by X-ray diffraction determination. It is found that some interm... YAG: Ce^3 + phosphor particles were prepared using polyacrylamide gel method. The structure evolution of powders during annealing process was followed by X-ray diffraction determination. It is found that some intermediate phases, including θ-Al2O3, YAM and YAP, are formed when calcining polyacrylamide gel, however, the pure YAG phase can be formed directly when calcining polyacrylamide gel with α-Al2O3 as seed crystal. These facts show that the existence of α- Al2O3 seed crystal can block the formation of θ-Al2O3, YAM and YAP, and accelerate its reaction with Y2O3 to form YAG phase directly at lower temperature. The emission peak of prepared YAG : Ce^3 + phosphor is wide with maximum at 550 nm and the exitation band has two peaks, the major one is around at 460 nm, which matches the blue emission of GaN LED and is suitable for the assemble of white LED. Some fluxes can enhance the photoluminescence intensity of phosphor particles, that can be attributed both to the improvement of crystallization processes of YAG and to the stabilization of trivalence cerium ion in YAG:Ce^3 +. 展开更多
关键词 YAG Ce^3 phosphor polyacrylamide gel α-Al2O3 seed crystal phase formation rare earths
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Molecular Simulations of the Effect of Hydrated Montmorillonite on the Viscosity of Polyacrylamide under Confined Shear 被引量:3
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作者 李文卓 WANG Jianlong XU Dingjia 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2015年第3期556-561,共6页
Our researches are based on the fact that the systems composed of polyacrylamide and montmorillonite under a kind of shear state often appear in some important practical processes like drilling well etc. The viscosity... Our researches are based on the fact that the systems composed of polyacrylamide and montmorillonite under a kind of shear state often appear in some important practical processes like drilling well etc. The viscosity of polyacrylamide is usually the most important one among the characteristics to decide if the practical processes succeed or not. Therefore, we studied the effect of hydrated montmorillonite on the viscosities of polyacrylamide with temperature and shear rate varying under confined shear by molecular simulation method. Adopting the condition of confined shear in the research could make our simulations and the practical processes as similar as possible. First, the model of one polyacrylamide polymer chain with 20 monomers linearly linking surrounded by water molecules between two of montmorillonite layers was constructed. Then canonical ensemble (NVT) MD simulations were carried out for the built model at different temperatures and shear rates. From the gained simulation results, we calculated the polymer's structural property-radius of gyration, which was directly related to the viscosity property of polyacrylamide polymer. It was found that the viscosity of the polyacrylamide polymer between hydrated clay layers decreased with the temperature increasing from 298 to 343 K under the condition of confined shear. The variation trend of viscosity from simulation results was also confirmed by our experiments. Besides, the viscosity of the polyacrylamide between hydrated clay layers decreased with the shear rate increasing within the range of higher shear rates. 展开更多
关键词 molecular simulation polyacrylamide MONTMORILLONITE confined shear VISCOSITY
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Preparation of Dysprosium Ferrite/Polyacrylamide Magnetic Composite Microsphere and Its Characterization 被引量:3
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作者 雄泽英博 王志峰 +3 位作者 周兰香 张红 李幼荣 张明 《Journal of Rare Earths》 SCIE EI CAS CSCD 2005年第3期262-265,共4页
Using the technique of microemulsion polymerization with nano-reactor, dysprosium ferrite/polyacrylamide magnetic composite microsphere was prepared by one-step method in a single inverse microemulsion. The structure,... Using the technique of microemulsion polymerization with nano-reactor, dysprosium ferrite/polyacrylamide magnetic composite microsphere was prepared by one-step method in a single inverse microemulsion. The structure, average particle size, morphology of composite microsphere were characterized by FTIR, XRD, TEM and TGA. The magnetic responsibility of composite microsphere was also investigated. The results indicate that the magnetic composite microsphere possess high magnetic responsibility and suspension stability. 展开更多
关键词 dysprosium ferrite polyacrylamide composite microsphere magnetic polymer microsphere rare earths
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Determination of the Structure of Polyacrylamide/Aluminum Citrate Colloidal Dispersion Gel System 被引量:2
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作者 彭勃 李明远 +1 位作者 纪淑玲 吴肇亮 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 1998年第2期81-83,共3页
1 INTRODUCTIONIn recent years,colloidal dispersion gel(CDG)have been attracting more and more in thefield of enhanced oil recovery on account of the cost-effectiveness and high efficiency ofblocking formation.Compared... 1 INTRODUCTIONIn recent years,colloidal dispersion gel(CDG)have been attracting more and more in thefield of enhanced oil recovery on account of the cost-effectiveness and high efficiency ofblocking formation.Compared with bulk gel(BG),CDG exhibits lower polymer concentra-tion,undefined shape and selective blocking formation characteristics.The characteris-tics of CDG and BG are related to structure.In the bulk gel a continuous network of polymermolecules is formed predominant through intermolecular cross-linkages.The 展开更多
关键词 polyacrylamide COLLOIDAL DISPERSION GEL CROSSLINKING system photomicrograph
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