期刊文献+
共找到2,605篇文章
< 1 2 131 >
每页显示 20 50 100
Alkali Tolerance of Concrete Internal Curing Agent Based on Sodium Carboxymethyl Starch
1
作者 陈梅花 刘荣进 +3 位作者 CHEN Ping JING Daiyan WAN Dandan FU Siyuan 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2024年第1期82-90,共9页
Internal curing agents (ICA) based on super absorbent polymer have poor alkali tolerance and reduce the early strength of concrete.An alkali tolerate internal curing agent (CAA-ICA) was designed and prepared by using ... Internal curing agents (ICA) based on super absorbent polymer have poor alkali tolerance and reduce the early strength of concrete.An alkali tolerate internal curing agent (CAA-ICA) was designed and prepared by using sodium carboxymethyl starch (CMS) with high hydrophilicity,acrylic acid (AA) containing anionic carboxylic group and acrylamide (AM) containing non-ionic amide group as the main raw materials.The results show that the ratio of CAA-ICA alkali absorption solution is higher than that existing ICA,which solves the low water absorption ratio of the ICA in alkali environment.The water absorption ratio of CAA-ICA in saturated Ca(OH)_(2) solution is 95.8 g·g^(-1),and the alkali tolerance coefficient is 3.4.The application of CAA-ICA in cement-based materials can increase the internal relative humidity and miniaturize the pore structure.The compressive strength of mortar increases up to 12.95%at 28 d,which provids a solution to overcome the reduction of the early strength. 展开更多
关键词 alkali tolerance sodium carboxymethyl starch internal curing agent compressive strength
下载PDF
Synthesis of Ionic and Non-Ionic Modified Waterborne Polyurethane Curing Agent
2
作者 Ying Qiao Xu-dong Zhang 《Journal of Electronic Research and Application》 2024年第1期86-92,共7页
By using HDI and TMP as the main raw materials,polyethylene glycol 400(PEG400)is used as a non-ionic hydrophilic modifier,and sodium hydroxyethyl sulfonate is used as an ionic hydrophilic modifier to synthesize a dual... By using HDI and TMP as the main raw materials,polyethylene glycol 400(PEG400)is used as a non-ionic hydrophilic modifier,and sodium hydroxyethyl sulfonate is used as an ionic hydrophilic modifier to synthesize a dual hydrophilic modified polyurethane curing agent.Research revealed that introducing PEG400 for hydrophilic chain segments and sodium hydroxyethyl sulfonate for hydrophilic ionic groups in the polyurethane curing agent component leads to a uniform distribution of hydrophilic components,significantly enhancing compatibility with the aqueous polyol component,and results in excellent film performance.The synthesis process and film were characterized using Fourier transform infrared spectroscopy and high-resolution scanning electron microscopy in the study. 展开更多
关键词 COATING Water polyurethane curing agent Two-package Double modification
下载PDF
Solidification Efficiency and Mechanism of Conventional Curing Agents for Sewage Sludge Stabilization and Dewatering 被引量:1
3
作者 Siliang Li Liangliang Wei +1 位作者 Qingliang Zhao Lu Li 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2015年第6期1-10,共10页
One of the challenges faced by sewage sludge treatment and disposal is its higher water content,and how to efficient dewater those hazardous materials properly is welcome in practice. This study stabilized the sewage ... One of the challenges faced by sewage sludge treatment and disposal is its higher water content,and how to efficient dewater those hazardous materials properly is welcome in practice. This study stabilized the sewage sludge via the using of conventional curing agents and calcined aluminum salts,and the corresponding dewatering mechanisms and structural changes of the stabilized sludge were further comparable analyzed.Experimental results showed that wollastonite and kaolin exhibit a relative higher dewatering efficiency as compared to other conventional curing agents; however the releasing rate of heavy metals of Cu,Cr,Ni for kaolin solidification and Zn,Pb for wollastonite solidification is higher than the sludge samples solidified by other curing agents. For comparison,the sludge samples solidified by calcined aluminum salts (AS),calcium ash,Mg-based curing agent,tricalcium aluminate( C_3A) show a lower heavy metals leaching potential and unconfined compressive strength. In addition,the economic characteristics and local availability of AS,calcium ash,C_3A and CaO makes it have a broad prospect in extension and application. These findings are of great significance for stabilization and dewatering of sewage sludge. 展开更多
关键词 sludge dewatering curing agents SOLIDIFICATION/STABILIZATION heavy metal leaching
下载PDF
Synthesis and Characterization of Waterborne Epoxy Curing Agent Modified by Silane 被引量:28
4
作者 卢光岐 孙建中 周其云 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2007年第6期899-905,共7页
A novel waterborne epoxy curing agent was prepared using 3-glycidoxypropyl trimethoxysilane (GPTMS) as a termination agent of adduct, which was synthesized by triethylene tetramine (TETA) and liquid epoxy resin (... A novel waterborne epoxy curing agent was prepared using 3-glycidoxypropyl trimethoxysilane (GPTMS) as a termination agent of adduct, which was synthesized by triethylene tetramine (TETA) and liquid epoxy resin (E-51). The effects of the reaction temperature and time on the synthesis process were investigated experimentally. The particle size and the distribution of water dispersion of the curing agent were measured by dynamic light scattering(DLS). The structure of the products was characterized by Fourier transform infrared spec-trometer (FTIR) and ^1H-nuclear magnetic resonance (^1H NMR). The properties of the synthesized curing agent and the epoxy resin film cured by it were also measured. The results showed that the appropriate temperature for the synthesis of adduct was at 65-75℃ and the reaction time was 4-5h, and that the suitable reaction temperature of curing agent synthesis was 75-85℃ and the reaction time was 3-4h. When the mass ratios of GPTMS and acetic acid were 3%-5% and 5%-10% respectively, the hardness, water resistance and adhesion of the cured film were improved significantly. 展开更多
关键词 waterborne epoxy curing agent SILANE MODIFICATION
下载PDF
Synthesis and Curing Properties of a Novel Novolac Curing Agent Containing Naphthyl and Dicyclopentadiene Moieties 被引量:8
5
作者 任华 孙建中 +1 位作者 吴斌杰 周其云 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2007年第1期127-131,共5页
A novel novolac curing agent containing both naphthalene and dicyclopentadiene (DCPD) moieties was prepared to produce a highly heat-resistant cured polymer network. The chemical structure was characterized using Four... A novel novolac curing agent containing both naphthalene and dicyclopentadiene (DCPD) moieties was prepared to produce a highly heat-resistant cured polymer network. The chemical structure was characterized using Fourier transform infrared spectroscopy, nuclear magnetic resonance, mass spectrometry, and gel permeation chro-matography analyses. The thermal properties of the resulting polymer from diglycidyl ether of bisphenol A epoxy resin cured with the novel curing agent were evaluated using dynamic mechanical thermal analysis and thermogra-vimetric analysis. Compared with the conventional curing agent, the resulting polymer cured with naphtha-lene/DCPD navolac shows considerable improvement in heat resistant properties such as higher glass transition temperature (Tg) and thermal stability. The result also shows better moisture resistance because of the hydrophobic nature of naphthalene/DCPD structure. 展开更多
关键词 epoxy curing agent heat resistance NAPHTHOL DICYCLOPENTADIENE
下载PDF
Solidification/stabilization of Dewatered Sludge with Multi-Component Solidifying Agents 被引量:1
6
作者 Jun-Qiu Jiang Kun Wang +3 位作者 Zi-Ye Li Yang Li Qing-Liang Zhao Guang-Yi Liu 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2013年第6期46-52,共7页
This work experimentally examined the optimal proportioning of sludge curing agent for dewatered sludge curing on solidified sludge,two components sludge curing agent consisted of cement and slag,and three components ... This work experimentally examined the optimal proportioning of sludge curing agent for dewatered sludge curing on solidified sludge,two components sludge curing agent consisted of cement and slag,and three components consisted of cement,slag and inorganic salt. The results showed that,increasing of curing ages could increase unconfined compressive strength and reduce moisture content for solidified sludge. For the test of two components,the biggest unconfined compressive strength of the solidified sludge achieved to 543. 72 kPa and the minimum moisture content achieved to 3. 56% of 21 d. The optimum proportion of the sludge curing agent of two components is sludge: cement: slag = 1 ∶ 0. 05 ∶ 0. 2 which selected by Design-expert. It could rapidly increasing the unconfined compressive strength of solidified sludge when added three components sludge curing agent( sludge: cement: slag: MgSO4= 1 ∶ 0. 05 ∶ 0. 2 ∶ 0. 03) on sludge curing. The results showed that,curing ages of 7 d,the unconfined compressive strength could achieve to 126. 74 kPa,which was more than 11 times comparison with the solidified sludge curing by two components curing agent. Two or three components sludge curing agent all could stabilize the heavy metals on solidified sludge and the leaching of heavy metals was below the government standard,while the stability of the heavy metals was superior for three components sludge curing agent. 展开更多
关键词 dewatered sludge SOLIDIFICATION curing agent stabilizationCLC number:X705 Document code:AArticle ID:1005-9113(2013)06-0046-07
下载PDF
Preparation of aqueous dispersion of epoxy curing agent with specially synthesized phase inversion emulsifier 被引量:4
7
作者 周继亮 涂伟萍 胡剑青 《化工学报》 EI CAS CSCD 北大核心 2005年第10期2029-2032,共4页
关键词 相反转乳化剂 水基环氧固化剂分散体 制备方法 理化性能
下载PDF
Control Effect of Different Microbial Agents on Tobacco Bacterial Wilt 被引量:5
8
作者 Li Xiaolong Shen Jianping +2 位作者 Yang Zhanwei Li Hongli Wang Yan 《Plant Diseases and Pests》 CAS 2017年第3期35-38,共4页
[ Objectives] The paper was to study effects of different microbial agents on occurrence of tobacco bacterial wilt. [ Methods I Antagonistic strains against Ralstonia solanacearum were screened from in situ soil, and ... [ Objectives] The paper was to study effects of different microbial agents on occurrence of tobacco bacterial wilt. [ Methods I Antagonistic strains against Ralstonia solanacearum were screened from in situ soil, and prepared into four different combinations. The number of soil microorganisms and incidence of bacterial wilt of four combinations were observed. [ Results] The incidence rate of bacterial wilt treated by microbial agent OR-1 was significantly lower than that in control, and the control efficacy against bacterial wilt reached 67%. [ Conclusions] Application of microbial agent OR-1 could effectively reduce the incidence rate and disease index of bacterial wilt, thus improving the quality of tobacco. 展开更多
关键词 Microbial agent Flue-cured tobacco Bacterial wilt
下载PDF
Investigation of the role of aziridine bonding agents on the aging of the composite solid rocket propellant(CSRP) 被引量:2
9
作者 Amged A Ali ZHANG Jian-wei CAI Guo-biao 《航空动力学报》 EI CAS CSCD 北大核心 2008年第11期2101-2106,共6页
The role of bonding agents on the aging characteristics is one of the important research topics.Aging program of the prepared propellant samples was conducting as follows:Five samples,two free of bonding agents,and th... The role of bonding agents on the aging characteristics is one of the important research topics.Aging program of the prepared propellant samples was conducting as follows:Five samples,two free of bonding agents,and three containing an aziridine based bonding agents(MAPO,HX-752,MAT4),four samples based on different bonding and curing agents all were aged at 70 ℃.The prepared bonding agent "MAT4" gave remarkable improvements and resulted in highly stable mechanical properties comparing with HX-752 or MAPO.The selected bonding agents family inhibited the rate of decomposition of the propellants during the aging periods and supported the propellant matrix against decomposition at the elevated temperatures. 展开更多
关键词 氮丙啶黏结剂 老化现象 复合固体火箭推进剂 航空动力系统
下载PDF
PREPARATION AND PROPERTIES OF THERMOSETTING ACRYLIC COATINGS USING TITANIUM-OXO-CLUSTER AS A CURING AGENT
10
作者 周树学 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2009年第3期351-358,共8页
Thermosetting acrylic coatings were prepared by using carboxyl acid group-containing acrylic oligomer and curing with titanium-oxo-clusters which were first pre-hydrolyzed from titanium n-butoxide.The curing ability o... Thermosetting acrylic coatings were prepared by using carboxyl acid group-containing acrylic oligomer and curing with titanium-oxo-clusters which were first pre-hydrolyzed from titanium n-butoxide.The curing ability of the titanium-oxo-cluster was examined using a microdielectric analytical(DEA)curing monitor,Fourier transformed infrared spectroscopy(FTIR),and Soxhlet extraction experiments,and the properties of the resulted coatings were investigated with pendulum hardness tester,dynamic mechanical analysis(DMA),thermogravimetric analysis(TGA)and ultraviolet-visible spectrometer.The effect of titania-oxo-cluster in leading acrylic oligomers to form thermosetting acrylic coatings was confirmed.An increasing pendulum hardness and modulus of acrylic coatings with increasing titania content was observed, which resulted from the increment of crosslinking degree rather than of the titania content.The thermosetting acrylic/titania coatings also showed better thermal stability and higher UV-blocking properties than those coatings using organic curing agent. 展开更多
关键词 Acrylic resin TITANIA Thermosetting coating curing agent
下载PDF
Influence of CaO-based expansive agent,superabsorbent polymers and curing temperature on pore structure evolution of early-age cement paste
11
作者 ZHAO Hai-tao LI Xiao-long +5 位作者 XIE Dong-sheng DI Yun-fei HUANG Jie XU Wen WANG Peng-gang ZUO Jun-qing 《Journal of Central South University》 SCIE EI CAS CSCD 2022年第5期1663-1673,共11页
Cracks easily generate in concrete at early age owing to the shrinkage deformation.CaO-based expansion agent(CEA)and superabsorbent polymers(SAP)have been extensively used for the mitigation of concrete shrinkage.The ... Cracks easily generate in concrete at early age owing to the shrinkage deformation.CaO-based expansion agent(CEA)and superabsorbent polymers(SAP)have been extensively used for the mitigation of concrete shrinkage.The macroscopic properties of concrete are highly determined by the microstructure.In this study,the influence of CEA and SAP addition on the pore structure evolution of cement paste under different curing temperatures was evaluated via low-field nuclear magnetic resonance spectroscopy.Test results indicated that,in cement paste,a higher CEA content led to a higher porosity and a larger most probable pore diameter(MPPD).Meanwhile,SAP addition increased the porosity and MPPD of CEA cement paste at early age but decreased them after 7 d,and a higher SAP content always brought a higher porosity and MPPD.Furthermore,the addition of SAP led to a lower porosity and MPPD of CEA cement paste than that of plain cement paste after 14 d.Moreover,the porosity and MPPD of CEA cement paste decreased first and subsequently increased as the curing temperature raised. 展开更多
关键词 cement paste pore structure CaO-based expansion agent superabsorbent polymers curing temperature low-field nuclear magnetic
下载PDF
施用不同有益菌剂对长期连作烤烟根际土壤微生态的影响 被引量:1
12
作者 王政 刘久羽 +3 位作者 李智 李博 李莹 敖金成 《西南农业学报》 CSCD 北大核心 2024年第3期612-621,共10页
【目的】探究不同有益菌剂对长期连作烤烟根际土壤微生态环境的影响,为连作土壤改良及连作障碍消减提供参考依据。【方法】采用盆栽试验和高通量测序技术,分析长期连作烤烟后添加有益菌哈茨木霉菌剂T-22(T1处理)、枯草芽孢杆菌剂(T2处理... 【目的】探究不同有益菌剂对长期连作烤烟根际土壤微生态环境的影响,为连作土壤改良及连作障碍消减提供参考依据。【方法】采用盆栽试验和高通量测序技术,分析长期连作烤烟后添加有益菌哈茨木霉菌剂T-22(T1处理)、枯草芽孢杆菌剂(T2处理)、哈茨木霉菌剂T-22+枯草芽孢杆菌剂(T3处理)的烤烟根际土壤理化性质、酶活性及微生物群落结构和功能。【结果】相较于不施有益菌(对照,CK),施用有益菌剂可提高长期连作烤烟根际土壤的速效养分含量和酶活性,其中,在10个环境因子中,速效磷(AP)含量对烤烟根际土壤细菌群落分布的贡献度(4.97%)最高,碱解氮(AN)含量对烤烟根际土壤真菌群落分布的贡献度(6.91%)最高,蔗糖酶(SC)活性对烤烟根际土壤真菌群落分布的贡献度(6.75%)次之;施用有益菌剂可提高长期连作烤烟根际土壤微生物群落丰度、多样性指数和细菌特有OTUs数;施用有益菌剂可改变长期连作烤烟根际土壤的指示物种丰度,其中,细菌假单胞菌属(Pseudomonas)为T1处理的指示物种,鞘氨醇单胞菌属(Sphingomonas)和被孢霉属(Mortierella)为T1处理的优势菌属,丰度分别为12.2%和25.0%,Minimedusa属为T3处理的指示物种。单施细菌有益菌剂可降低长期连作烤烟根际土壤细菌群落主要代谢途径的丰度,单施真菌有益菌剂则相反;单施真菌、细菌与真菌有益菌剂混施可提高烤烟根际土壤真菌代谢途径的丰度。【结论】施用有益菌剂对长期连作烤烟根际土壤微生态环境具有一定的改良效应,其中,哈茨木霉T-22的施用效果较好,可用于烤烟连作障碍防控。 展开更多
关键词 烤烟 长期连作 土壤微生态环境 土壤酶活性 有益菌剂 高通量测序
下载PDF
有机肥+生物炭+微生物菌剂配施对烤烟多酚和化学成分的影响
13
作者 严锦申 李琳霖 +5 位作者 袁文彬 杨天旭 邵兰军 王维 温润豪 黄瑞寅 《江西农业学报》 CAS 2024年第2期61-67,共7页
以云烟87为研究对象,采用三因素三水平正交试验设计,设置3个生物炭(900、1800、2700 kg/hm^(2))、3个微生物菌剂(30、60、90 kg/hm^(2))和3种有机肥(羊粪肥、芝麻饼肥、菜籽饼肥)组合成9个处理,并以无机肥为对照处理,研究了上述因素对... 以云烟87为研究对象,采用三因素三水平正交试验设计,设置3个生物炭(900、1800、2700 kg/hm^(2))、3个微生物菌剂(30、60、90 kg/hm^(2))和3种有机肥(羊粪肥、芝麻饼肥、菜籽饼肥)组合成9个处理,并以无机肥为对照处理,研究了上述因素对烤后烟叶多酚类和常规化学成分的影响。结果表明:生物炭施用量是影响烤烟的多酚和化学成分含量的主效因素,随着生物炭施用量的增加,烟叶的总糖、还原糖及各种多酚类物质含量均有所增加,施用2700 kg/hm^(2)生物炭的整体表现较优。微生物菌剂也是重要的影响因素,随着微生物菌剂施用量的增加,烟叶的总糖、还原糖、多酚类、绿原酸含量均有所增加,施用60 kg/hm^(2)微生物菌剂的整体表现较优。施用有机肥的影响则较小,其中,羊粪肥的表现相对较好。综上,最佳组合方式为2700 kg/hm^(2)生物炭+60 kg/hm^(2)微生物菌剂+羊粪肥,并且将其可应用于凉山产区烤烟的施肥管理中。 展开更多
关键词 烤烟 生物炭 微生物菌剂 多酚 化学成分
下载PDF
基于响应面法的碱硫酸盐激发固废型固化剂组成优化设计 被引量:1
14
作者 李悦 刘学磊 +2 位作者 林辉 穆金磊 李亚强 《建材世界》 2024年第2期10-14,共5页
论文采用响应面法对碱-硫酸盐激发固废型固化剂体系进行优化,以赤泥、矿渣、生石灰和脱硫石膏为变量因素,以流态固化土的7 d、28 d无侧限抗压强度和流动扩展度为评价指标,建立预测模型。结果表明:当赤泥掺量为26.6%、矿渣掺量为53.2%、... 论文采用响应面法对碱-硫酸盐激发固废型固化剂体系进行优化,以赤泥、矿渣、生石灰和脱硫石膏为变量因素,以流态固化土的7 d、28 d无侧限抗压强度和流动扩展度为评价指标,建立预测模型。结果表明:当赤泥掺量为26.6%、矿渣掺量为53.2%、石灰掺量为11.7%、脱硫石膏掺量为8.5%时,流态固化土的工作性能和力学性能均达到最优,响应值的实测值和预测值误差范围控制在5%内,表明该响应面法预测模型预测精度高。 展开更多
关键词 固化剂 赤泥 响应面法 多目标优化
下载PDF
保水剂施用量对西南紫色土水分和养分特征及烟叶品质的影响
15
作者 周萍 方珂 +5 位作者 赵楠 鞠臻 庄文化 杨军伟 叶田会 张丹 《水土保持研究》 CSCD 北大核心 2024年第5期53-63,共11页
[目的]揭示保水剂聚丙烯酸钾不同施用量对西南烟区紫色土水分、土壤孔隙状况、土壤养分特征及烟叶品质的影响,为缓解季节性干旱区植烟土壤水分缺乏及高产优质的烟草生产提供重要参考。[方法]采用随机区组设计,定量研究了不同保水剂施用... [目的]揭示保水剂聚丙烯酸钾不同施用量对西南烟区紫色土水分、土壤孔隙状况、土壤养分特征及烟叶品质的影响,为缓解季节性干旱区植烟土壤水分缺乏及高产优质的烟草生产提供重要参考。[方法]采用随机区组设计,定量研究了不同保水剂施用量条件下的紫色土水分、养分及烟叶品质特征。[结果]保水剂添加后,土壤pH值变化范围为7.4~7.7,土壤总孔隙度、毛管孔隙度、土壤饱和含水量、田间持水量、毛管含水量均呈先增大后减小变化规律,当保水剂施用量为150 kg/hm^(2)时,土壤容重达到最低值,土壤总孔隙度和毛管孔隙度、土壤饱和含水量、毛管含水量均达到最大值。土壤的阳离子交换量(CEC值)呈现出波动式变化。土壤有机碳、全钾和速效钾含量随着保水剂施用量的增加呈先增加后降低的趋势,土壤全氮、全磷、碱解氮和速效磷含量呈逐渐增加趋势。土壤容重呈现出先减小后增大的趋势。烟叶氯含量、总氮含量变化为上部叶<中部叶<下部叶。随着保水剂施用浓度的增加,烟叶氯含量呈波动变化。中上部烟叶含钾量高于下部烟叶含钾量且随保水剂施用浓度的增加略有增加。烟碱含量变化为上部叶>中部叶>下部叶,且烟碱含量与保水剂施用浓度相关性较弱。烟叶还原糖和总糖的变化趋势较为一致。不同部位的烟叶钾氯比表现为上部叶>中部叶>下部叶,且最随着保水剂施用浓度的增加,烟叶钾氯比呈波动态变化。不同叶位烟碱/总氮比和糖碱比均表现为上部叶<中部叶<下部叶,且随着保水剂浓度的增大,均表现为递增趋势。植烟土壤全氮含量与不同叶位的烟叶氯含量、上部叶含钾量、还原糖含量之间均呈显著正相关关系(p<0.05)。不同叶位烟叶氯含量、还原糖含量、上部烟叶钾含量、下部烟叶烟碱含量均与土壤有机碳间存在显著正相关关系(p<0.05)。[结论]保水剂为150 kg/hm^(2)对于西南紫色土的改良效果最佳,研究可为植烟土壤抗旱性能增强及烟叶品质的提升提供科学依据。 展开更多
关键词 保水剂 土壤水分 土壤养分 烟叶品质指标 相关关系
下载PDF
酸酐固化剂复配对环氧树脂复合材料性能分散度的影响
16
作者 赵玉顺 白金辉 +3 位作者 罗子民 闫程 王琨 杨威 《高压电器》 CAS CSCD 北大核心 2024年第8期221-229,共9页
酸酐固化剂因具有耐热性好、固化收缩小、绝缘性能好等优点,被广泛应用于电力装备用环氧树脂复合材料浇注体系。电力系统正在向高电压、大容量方向发展,对电力装备性能提出了更高要求。为获得高性能环氧复合绝缘材料,文中研究了5种常用... 酸酐固化剂因具有耐热性好、固化收缩小、绝缘性能好等优点,被广泛应用于电力装备用环氧树脂复合材料浇注体系。电力系统正在向高电压、大容量方向发展,对电力装备性能提出了更高要求。为获得高性能环氧复合绝缘材料,文中研究了5种常用酸酐固化剂对环氧复合材料性能的影响,发现苯酐存在固化物性能优异,但有固化工艺性差、固化物性能分散度大的问题。进一步,制备了苯酐/六氢苯酐复配固化剂,并研究了复配固化剂对环氧复合材料机械性能和电气性能的影响。实验结果表明,当苯酐/六氢苯酐复配摩尔比例为1∶3时,复配固化剂的熔点最低、固化工艺性较好,固化产物的拉伸、弯曲和击穿强度最大值虽略有降低,但平均值提升显著,分散度显著减小,且耐电弧性能提高了49%。 展开更多
关键词 酸酐固化剂 电力装备 复配固化剂 分散度
下载PDF
多孔环氧树脂基固体电解质微观结构与性能
17
作者 孙小巍 刘帅 +2 位作者 叶金蕊 雷琴 姬晓龙 《高分子材料科学与工程》 EI CAS CSCD 北大核心 2024年第6期9-16,共8页
文中以聚乙二醇200为制孔剂、双酚A二缩水甘油醚为树脂基体、4,4'-二氨基二环己基甲烷(PACM)和聚醚胺(D230)为固化剂,使用反应诱导相分离法制备了多种多孔环氧树脂,研究了制孔剂比例与固化剂种类对多孔环氧树脂微孔结构的影响。结... 文中以聚乙二醇200为制孔剂、双酚A二缩水甘油醚为树脂基体、4,4'-二氨基二环己基甲烷(PACM)和聚醚胺(D230)为固化剂,使用反应诱导相分离法制备了多种多孔环氧树脂,研究了制孔剂比例与固化剂种类对多孔环氧树脂微孔结构的影响。结果表明,随着制孔剂比例增加,PACM体系多孔环氧树脂微孔结构由非贯通圆孔变为由环氧树脂小球连接的贯通结构,而D230体系多孔环氧树脂由独立小孔逐渐发展为三维骨架孔道。D230三维贯通骨架结构更利于制孔剂的去除和离子通道的形成,可在保留较完整树脂骨架的同时获得较高离子电导率(1.81 mS/cm);而PACM海绵状微孔更容易形成闭合孔道,在制孔剂与树脂质量比超过3:1的情况下可获得较高离子电导率(2.02 mS/cm),但此时微观形貌表现为独立树脂小球,失去力学性能。此外,在制备的树脂固体电解质块体结构中,D230体系在更低的制孔剂比例下(制孔剂与树脂质量比为2:1)测得离子电导率(0.35mS/cm),表明大厚度条件下,D230体系三维网络结构对比PACM体系圆孔更有利于形成连续离子通道。 展开更多
关键词 制孔剂 固化剂 多孔环氧树脂 微观形貌
下载PDF
水泥固化土固化机理及抗冲刷特性
18
作者 王秋生 修一兵 +2 位作者 齐云鹏 邓启华 李广耀 《长江科学院院报》 CSCD 北大核心 2024年第8期142-149,共8页
为了完善水泥固化土抗冲刷性能方面的研究,使水泥固化土在水下结构防护中得到应用,在砂土和黏土中分别掺入水泥和与液体固化剂,采用土体冲刷函数测定仪(EFA)对水泥固化土开展了抗冲刷性能试验。在分析砂土和黏土的固化作用机理基础上,... 为了完善水泥固化土抗冲刷性能方面的研究,使水泥固化土在水下结构防护中得到应用,在砂土和黏土中分别掺入水泥和与液体固化剂,采用土体冲刷函数测定仪(EFA)对水泥固化土开展了抗冲刷性能试验。在分析砂土和黏土的固化作用机理基础上,研究了固化剂和固化时间对水泥固化土抗冲刷性能的影响。研究结果表明:水泥固化土的强度随固化时间的增长而增大,黏土的强度快速增长阶段要早于砂土;固化剂可以有效提高土体的起动切应力,同时可以大幅减小土体的冲刷速率,明显提高了土体的抗冲刷强度;起动切应力的增长速率随固化时间增长逐渐减缓,存在临界最大值。根据起动切应力的变化特征提出了水泥固化土起动切应力预测模型,经试验数据对比,该模型可以较好地预测水泥固化土的起动切应力随固化时间的变化规律。 展开更多
关键词 水泥固化土 固化时间 固化剂 固化机理 抗冲刷 起动切应力
下载PDF
水泥基材料无机/有机复合内养护剂的研究进展
19
作者 夏慧芸 吕昕 +3 位作者 张耿通 杨国龙 宋莉芳 牛艳辉 《功能材料》 CAS CSCD 北大核心 2024年第2期2082-2090,共9页
无机/有机复合吸水材料具有一定的亲水基团和三维网络结构,吸水性、保水性和释水性优异,是水泥基材料重要的内养护剂之一。通过在水泥基材料中引入无机/有机复合吸水材料,利用其吸-释水特性可自动调节水泥基材料内部相对湿度,促进水化反... 无机/有机复合吸水材料具有一定的亲水基团和三维网络结构,吸水性、保水性和释水性优异,是水泥基材料重要的内养护剂之一。通过在水泥基材料中引入无机/有机复合吸水材料,利用其吸-释水特性可自动调节水泥基材料内部相对湿度,促进水化反应,减少水泥基材料自收缩和早期开裂等现象,提高力学性能和耐久性。概述了无机/有机复合内养护剂(CICA)的制备方法、结构特征以及吸-释水行为;综述了CICA对水泥基材料水化进程、微观结构、宏观性能和耐久性的影响;展望了CICA在混凝土应用的发展前景,为CICA在水泥基内养护中的应用提供一定理论指导和技术参考。 展开更多
关键词 复合内养护剂 吸-释水行为 自收缩 孔隙结构 力学性能
下载PDF
持续负温(-5℃)养护条件下含气混凝土性能劣化及孔结构发展规律试验研究
20
作者 张戎令 于博 郭海贞 《土木与环境工程学报(中英文)》 CSCD 北大核心 2024年第3期180-188,共9页
通过对比负温养护、标准养护条件下5种不同含气混凝土试块在不同龄期下的抗压强度值及内部孔结构,分析持续负温(-5℃)养护条件下含气混凝土抗压强度的发展规律,针对持续负温(-5℃)养护条件,对少害孔的范围进一步明确;并从混凝土内部孔... 通过对比负温养护、标准养护条件下5种不同含气混凝土试块在不同龄期下的抗压强度值及内部孔结构,分析持续负温(-5℃)养护条件下含气混凝土抗压强度的发展规律,针对持续负温(-5℃)养护条件,对少害孔的范围进一步明确;并从混凝土内部孔隙分布状况对引气类混凝土普遍存在的强度缺失进行研究。试验结果表明:持续负温(-5℃)条件养护对含气混凝土抗压强度的增长有明显的抑制作用,相同引气剂掺量下混凝土试块强度均小于标准养护试块的强度;同种养护条件下,受引气剂影响,混凝土的强度与引气剂掺量间均呈现负相关;在负温养护环境条件下,实验中设置的最高掺量(0.2%引气剂掺量组别)含气混凝土结构整体密实性因浆体内部孔隙数量的增加而减弱,对混凝土自身的强度有一定影响,但引气剂的加入对负温环境混凝土的抗冻作用不可忽视。为了分析负温环境与引气剂掺量之间的平衡性,通过对含气混凝土在不同养护条件下孔结构发展规律的研究,在保证含气混凝土抗压强度劣化程度低、孔径结构相对优化的前提下,明确了负温(-5℃)条件下含气混凝土引气剂的最优掺量。 展开更多
关键词 含气混凝土 引气剂 负温养护 抗压强度 孔结构
下载PDF
上一页 1 2 131 下一页 到第
使用帮助 返回顶部