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Wettability alteration of organo-vermiculites induced by layer charge and tailored bis-N-heterocyclic quaternary ammonium salts
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作者 Fan Ding Xin Jin +3 位作者 Tao Shen Shan-Shan Mao Qing Zhao Mang-Lai Gao 《Petroleum Science》 SCIE EI CAS CSCD 2023年第4期2596-2603,共8页
Wettability is an important surface property that deserves to further explore the factors on its alteration.Series of bis-N-heterocyclic quaternary ammonium salts with different spacer length and N-heterocyclic headgr... Wettability is an important surface property that deserves to further explore the factors on its alteration.Series of bis-N-heterocyclic quaternary ammonium salts with different spacer length and N-heterocyclic headgroups(morpholinium(BMMB,BMMD and BMMH),piperidinium(BPMH)and piperazinium(BMPMH))have been synthesized and employed for altering the wettability of vermiculite and its derivates(Vts)treated by Li^(+)-saturated heating method.The results of X-ray diffraction(XRD),Fourier transform infrared spectroscopy(FT-IR),thermogravimetric analysis(TG-DTG),scanning electron microscopy(SEM)and N_(2)adsorption/desorption isotherms indicate that all of the bis-N-heterocyclic quaternary ammonium salts have been successfully inserted into the vermiculite layers,leading to the organic monolayer.The results of capillary rise tests combined with Lipophilic to Hydrophilic Ratio(LHR)values unveil the wettability alteration of the organo-Vts.As the layer charge decreases,the hydrophilicity of the organo-Vts gradually increases,which is probably caused by the decline in binding sites.As the result of the change in spacer length of modifier,the wetting properties of morpholinium-based organo-Vts change in order of BMMD-Vts>BMMH-Vts>BMMB-Vts,and difference in N-heterocyclic headgroups leads to the sequence of wettability:BMPMH-Vts>BPMH-Vts>BMMH-Vts.Layer charge of Vt,spacer length and the type of the N-heterocyclic headgroup of modifier have the synergistic effect on the regulation of the wettability. 展开更多
关键词 VERMICULITE bis-N-heterocyclic quaternary ammonium SALTS Organo-vermiculite Layer charge Wettability alteration
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Studies on a Cationically Modified Quaternary Ammonium Salt of Lignin 被引量:18
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作者 YANG Ai-li JIANG Wen-ju 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2007年第4期479-482,共4页
A new quaternary ammonium salt monomer was synthesized and a quaternary amination of lignin( noted as QL), with the monomer was carried out by grafting copolymerization. The products were characterized by Fourier Tr... A new quaternary ammonium salt monomer was synthesized and a quaternary amination of lignin( noted as QL), with the monomer was carried out by grafting copolymerization. The products were characterized by Fourier Transform Infrared spectroscopy( FTIR). The experimental results indicate that the yield of the monomer was 99.06%, and the conversion of the monomer and the grafting yield of QL were 93.69% and 185.78%, respectively. The feasibility of QL as the flocculant to be applied in color removal of five artificial dyes, erioehrome black T(dye A), gongo red(dye B ), direct fast black G (dye C ), cuprofix blue green B (dye D ), and acid black ATT (dye E ) was examined. Results show that OL exhihits the favorable flocculation nerformance and high stability. 展开更多
关键词 quaternary ammonium salt of lignin(QL) Cationic monomer Grafting copolymerization FLOCCULATION
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Effects of quaternary ammonium chain length on the antibacterial and remineralizing effects of a calcium phosphate nanocomposite 被引量:15
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作者 Ke Zhang Lei Cheng +2 位作者 Michael D Weir Yu-Xing Bai Hockin HK Xu 《International Journal of Oral Science》 SCIE CAS CSCD 2016年第1期45-53,共9页
Composites containing nanoparticles of amorphous calcium phosphate (NACP) remineralize tooth lesions and inhibit caries. A recent study synthesized quaternary ammonium methacrylates (QAMs) with chain lengths (CLs... Composites containing nanoparticles of amorphous calcium phosphate (NACP) remineralize tooth lesions and inhibit caries. A recent study synthesized quaternary ammonium methacrylates (QAMs) with chain lengths (CLs) of 3-18 and determined their effects on a bonding agent. This study aimed to incorporate these QAMs into NACP nanocomposites for the first time to simultaneously endow the material with antibacterial and remineralizing capabilities and to investigate the effects of the CL on the mechanical and biofilm properties. Five QAMs were synthesized: DMAPM (CL3), DMAHM (CL6), DMADDM (CL12), DMAHDM (CL16), and DMAODM (CL18). Each QAM was incorporated into a composite containing 20% NACP and 50% glass fillers. A dental plaque microcosm biofilm model was used to evaluate the antibacterial activity. The flexural strength and elastic modulus of nanocomposites with QAMs matched those of a commercial control composite (n = 6; P 〉 0.1). Increasing the CL from 3 to 16 greatly enhanced the antibacterial activity of the NACP nanocomposite (P 〈 0.05); further increasing the CL to 18 decreased the antibacterial potency. The NACP nanocomposite with a CL of 16 exhibited biofilm metabolic activity and acid production that were 10-fold lesser than those of the control composite. The NACP nanocomposite with a CL of 16 produced 2-log decreases in the colony-forming units (CFU) of total microorganisms, total streptococci, and mutans streptococci. In conclusion, QAMs with CLs of 3-18 were synthesized and incorporated into an NACP nanocomposite for the first time to simultaneously endow the material with antibacterial and remineralization capabilities. Increasing the C/reduced the metabolic activity and acid production of biofilms and caused a 2-log decrease in CFU without compromising the mechanical properties. Nanocomposites exhibiting strong anti-biofilm activity, remineralization effects, and mechanical properties are promising materials for tooth restorations that inhibit caries. 展开更多
关键词 antibacterial nanocomposite calcium phosphate nanoparticles caries inhibition human saliva microcosm biofilm quaternary ammonium chain length
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Preparation of Hierarchically Trimodal-Porous ZSM-5 Composites through Steam-assisted Conversion of Macroporous Aluminosilica Gel with Two Different Quaternary Ammonium Hydroxides 被引量:8
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作者 Zhao Tianbo Wang Jia +1 位作者 Xu Xin Wang Guijie 《China Petroleum Processing & Petrochemical Technology》 SCIE CAS 2015年第1期48-58,共11页
This article presents a detailed structural study of a new spherical Mg Cl2-supported Ti Cl4 Ziegler-Natta catalyst for isotactic propylene polymerization, and researches on the relationship between catalyst structure... This article presents a detailed structural study of a new spherical Mg Cl2-supported Ti Cl4 Ziegler-Natta catalyst for isotactic propylene polymerization, and researches on the relationship between catalyst structure and polymer properties. The spherical support with the chemical composition of CH3CH2 OMg OCH(CH2Cl)2 has been synthesized from a new dispersion system and is used as the supporting material to prepare Ziegler-Natta catalyst. The XRD analysis indicates that the catalyst is fully activated with δ-Mg Cl2 in the active catalyst. The far-IR spectrometric results confirm again the presence of δ-Mg Cl2 in the active catalyst. Textural property of the active catalyst exhibits high surface area coupled with high porosity. The high activity in propylene polymerization is mainly ascribed to the full activation and the porous structure of the catalyst. Scanning electron microscopy/energy dispersive spectrometer mapping results indicate a uniform titanium distribution throughout the catalyst particles. Particle size analysis shows that the catalyst has a narrow particle size distribution. The perfect spherical shape, uniform titanium distribution and narrow particle size distribution of the catalyst confirm the advantage of polymer particles production with less fines. The solid state 13 C NMR and mid-IR spectroscopic analyses indicate that there exists strong complexation between diisobutyl phthalate and Mg Cl2, which leads to the high isotacticity of polypropylene. 展开更多
关键词 ZSM-5 composites hierarchically trimodal-porous steam-assisted CONVERSION method MACROPOROUS aluminosilicagel quaternary ammonium hydroxide
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Adsorption of methyl orange from aqueous solution by composite magnetic microspheres of chitosan and quaternary ammonium chitosan derivative 被引量:3
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作者 Bin Zhao Xiaojing Sun +3 位作者 Liang Wang Lixiang Zhao Zhaohui Zhang Junjing Li 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2019年第8期1973-1980,共8页
Novel composite magnetic microspheres containing chitosan and quaternary ammonium chitosan derivative(CHMMs) were prepared by inverse suspension method,and used for the methyl orange(MO) removal from aqueous solutions... Novel composite magnetic microspheres containing chitosan and quaternary ammonium chitosan derivative(CHMMs) were prepared by inverse suspension method,and used for the methyl orange(MO) removal from aqueous solutions.The CHMMs were characterized by a scanning electron microscope,a transmission electron microscope,and Fourier transform infrared spectroscopy,respectively.Compared with the chitosan beads,the incorporation of quaternary ammonium chitosan derivative significantly reduced the particle size.The MO adsorption by CHMMs was investigated by batch adsorption experiments.The adsorption kinetics was conformed to the pseudo second-order kinetics equation.The adsorption isotherm followed the Langmuir model better than the Freundlich model and the calculated maximum MO adsorption capacity was 266.6 mg·g^-1 at 293 K.Thermodynamic studies indicated that the MO adsorption was endothermic in nature with the enthalpy change(△H°) of 99.44 kJ·mol^-1.The CHMMs had a stable performance for MO adsorption in the pH range of 4-10,but high ionic strength deteriorated the MO removal due to the shielding of the ion exchange interaction.A 1 mol·L^-1 NaCl solution could be used to regenerate the exhausted CHMMs.The proposed CHMMs can be used as an effective adsorbent for dye removal or recovery from the dye wastewater. 展开更多
关键词 CHITOSAN quaternary ammonium CHITOSAN DERIVATIVE Waste water ADSORPTION Ion exchange
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Synthesis of isosorbide-based polycarbonates via melt polycondensation catalyzed by quaternary ammonium ionic liquids 被引量:11
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作者 Wei Sun Fei Xu +3 位作者 Weiguo Cheng Jian Sun Guoqing Ning Suojiang Zhang 《Chinese Journal of Catalysis》 EI CSCD 北大核心 2017年第5期908-917,共10页
A series of quaternary ammonium ionic liquids(ILs)were synthesized and employed as catalysts for the production of poly(isosorbide carbonate)(PIC)from diphenyl carbonate and isosorbide via a melt polycondensation proc... A series of quaternary ammonium ionic liquids(ILs)were synthesized and employed as catalysts for the production of poly(isosorbide carbonate)(PIC)from diphenyl carbonate and isosorbide via a melt polycondensation process.The relationship between the anions of the ILs and the catalytic activities was investigated,and the readily‐prepared IL tetraethylammonium imidazolate(TEAI)was found to exhibit the highest catalytic activity.After optimizing the reaction conditions,a PIC with a weight‐average molecular weight(Mw)of25600g/mol was obtained,in conjunction with an isosorbide conversion of92%.As a means of modifying the molecular flexibility and thermal properties of the PIC,poly(aliphatic diol‐co‐isosorbide carbonate)s(PAIC)s were successfully synthesized,again using TEAI,and polymers with Mw values ranging from29000to112000g/mol were obtained.13C NMR analyses determined that the PAIC specimens had random microstructures,while differential scanning calorimetry demonstrated that each of the PAICs were amorphous and had glass transition temperatures ranging from50to115°C.Thermogravimetric analyses found Td‐5%values ranging from316to332°C for these polymers.Based on these data,it is evident that the incorporation of linear or cyclohexane‐based diol repeating units changed the thermal properties of the PIC. 展开更多
关键词 quaternary ammonium ionic liquid catalyst ISOSORBIDE POLYCARBONATE Melt polycondensation Aliphatic diol
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Superoxide Anion Radical Scavenging Ability of Quaternary Ammonium Salt of Chitosan 被引量:5
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作者 XiaoYanZHU JianMinWU ZhiShenJIA 《Chinese Chemical Letters》 SCIE CAS CSCD 2004年第7期808-810,共3页
A series of N-alkyl or N-aryl chitosan quaternary ammonium salt were prepared using 96% deacetylated chitosan. Their scavenging activities against superoxide anion radical were investigated by chemiluminescence. The I... A series of N-alkyl or N-aryl chitosan quaternary ammonium salt were prepared using 96% deacetylated chitosan. Their scavenging activities against superoxide anion radical were investigated by chemiluminescence. The IC50 values of these compounds range from 280 to 880 μg/mL, which should be attributed to their different substitutes. 展开更多
关键词 Chitosan quaternary ammonium salts antioxidant activity chemiluminescence superoxide anion radical.
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Effect of quaternary ammonium salts on flotation behavior of aluminosilicate minerals 被引量:8
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作者 赵声贵 钟宏 刘广义 《Journal of Central South University of Technology》 EI 2007年第4期500-503,共4页
The electrokinetic properties and flotation of diaspore, kaolinite, pyrophyllite and illite with quaternary ammonium salts collectors were studied. The results of flotation tests show that the collecting ability of qu... The electrokinetic properties and flotation of diaspore, kaolinite, pyrophyllite and illite with quaternary ammonium salts collectors were studied. The results of flotation tests show that the collecting ability of quaternary ammonium salts for the four minerals is in the order(from strong to weak) ofoctadecyl dimethyl benzyl ammonium chloride(ODBA), cetyl trimethyl ammonium bromide(CTAB), dodecyl trimethyl ammonium chloride(DTAC). Under the condition of alkalescence, it is possible to separate the diaspore from the silicate minerals such as kaolinite, illite and pyrophyllite using quaternary ammonium salts as collector. Isoelectric points (IEP) of diaspore, kaolinite, pyrophyllite and illite are pH=6.0, 3.4, 2.3 and 3.2, respectively. Quaternary ammonium salts can change ζ-potential of the aluminosilicate minerals obviously. The flotation mechanisms were explained by ζ-potential and Fourier transform infrared spectrum (FT-IR) measurements. The results demonstrate that only electrostatic interaction takes place between aluminosilicate minerals (diaspore, kaolinite, pyrophyllite and illite) and quaternary ammonium salts. 展开更多
关键词 aluminosilicate mineral quaternary ammonium salt FLOTATION
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Dimethyl carbonate synthesis via transesterification catalyzed by quaternary ammonium salt functionalized chitosan 被引量:2
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作者 Yuan Zhao Liang Nian He +1 位作者 Yuan Yi Zhuang Jin Quan Wang 《Chinese Chemical Letters》 SCIE CAS CSCD 2008年第3期286-290,共5页
A quaternary ammonium salt covalently linked to chitosan was first used as a catalyst for dimethyl carbonate (DMC) synthesis by the transesterification of propylene carbonate (PC) with methanol. The effects of var... A quaternary ammonium salt covalently linked to chitosan was first used as a catalyst for dimethyl carbonate (DMC) synthesis by the transesterification of propylene carbonate (PC) with methanol. The effects of various reaction variables like reaction time, temperature and pressure on the catalytic performance were also investigated. 54% DMC yield and 71% PC conversion were obtained under the optimal reaction conditions. Notably, the catalyst was able to be reused with retention of high catalytic activity and selectivity. Consequently, the process presented here has great potential for industrial application due to its advantages such as stability, easy preparation from renewable biopolymer, and simple separation from products. 展开更多
关键词 CHITOSAN quaternary ammonium salt TRANSESTERIFICATION Dimethyl carbonate
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Quaternary ammonium-induced multidrug tolerant Streptococcus mutans persisters elevate cariogenic virulence in vitro 被引量:2
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作者 Ya-Ling Jiang Wei Qiu +8 位作者 Xue-Dong Zhou Hao Li Jun-Zhuo Lu Hockin HK Xu Xian Peng Ming-Yun Li Ming-Ye Feng Lei Cheng Biao Ren 《International Journal of Oral Science》 SCIE CAS CSCD 2017年第4期224-231,共8页
Dental caries are the most prevalent chronic infections in the oral cavity, and Streptococcus mutans acts as the main cariogenic bacterial species. Antibacterial quaternary ammonium compounds (QAs) have been develop... Dental caries are the most prevalent chronic infections in the oral cavity, and Streptococcus mutans acts as the main cariogenic bacterial species. Antibacterial quaternary ammonium compounds (QAs) have been developed to preveFnt or treat dental caries. However, there is no report on the tolerance of S. mutans to QAs. In this study, we investigated the development of S. mutans persistence induced by a novel dental caries defensive agent, dimethylaminododecyl methacrylate (DMADDM), for the first time. Typical biphasic killing kinetics for persisters were observed in both S. mutans planktonic and biofilm cultures challenged by DMADDM at concentrations of 20 and 200 pg.mL- z respectively. The persisters tolerated six other antibiotics with different antibacterial mechanisms, while only daptomycin and vancomycin could slightly reduce the persister numbers in planktonic cultures. The distribution of persisters in DMADDM-treated biofilms was similar to that in the untreated control, except that the total biomass and biofilm height were significantly reduced. A higher exopolysaccharides (EPS):bacteria ratio was observed in DMADDM-treated biofilms. Persisters in biofilms significantly upregulated gtf gene expression, indicating an increase in the bacteria's ability to produce EPS and an elevated capability of cariogenic virulence. Carbon source metabolism was significantly reduced, as related metabolic genes were all downregulated in persisters. Concentrations of 0.1 mM, 1 mM and 10 mM of extra glucose significantly reduced the number of persisters both in planktonic and biofilm conditions. The formation of non- inheritable and multidrug tolerant persisters induced by DMADDM suggested that drug tolerance and new persistent eradication strategies should be considered for oral antibacterial agents. 展开更多
关键词 antibacterial quaternary ammoniums dental caries PERSISTENCE multidrug tolerance Streptococcus mutans biofilms
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Direct synthesis of propylene carbonate from propylene and carbon dioxide catalyzed by quaternary ammonium heteropolyphosphatotungstate–TBAB system 被引量:2
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作者 Gongda Zhao Yi Zhang +2 位作者 Hengyun Zhang Jun Li Shuang Gao 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2015年第3期353-358,共6页
In this paper,we have developed a highly efficient method for the direct preparation of propylene carbonate from propylene and carbon dioxide(CO2) using quaternary ammonium heteropolyphosphatotungstate–quaternary a... In this paper,we have developed a highly efficient method for the direct preparation of propylene carbonate from propylene and carbon dioxide(CO2) using quaternary ammonium heteropolyphosphatotungstate–quaternary ammonium halide catalytic system with anhydrous hydrogen peroxide as an oxidant through one-pot two-step process.The effects of the amount of tetrabutylammonium bromide(TBAB),the concentration of hydrogen peroxide and other reaction conditions were investigated.The catalyst system gave an optimum propylene oxide yield(91%) at75°C in oxidation step and the highest propylene carbonate yield(99%) at 140°C and 3.0 MPa in cycloaddition step.Based on the results,a reaction mechanism has been proposed. 展开更多
关键词 quaternary ammonium heteropolyphosphatotungstate propylene carbonate carbon dioxide tetrabutylammonium bromide
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PREPARATION AND PHOTOSENSITIVITY OF WATER SOLUBLE PHENOLIC RESINS CONTAINING ACRYLOYL AND QUATERNARY AMMONIUM CHLORIDE GROUPS 被引量:2
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作者 谭晓明 《Chinese Journal of Polymer Science》 SCIE CAS CSCD 2002年第2期129-136,共8页
New water soluble and photocrosslinkable prepolymers containing acrylate and quaternary ammonium salt groups were synthesized from epoxy phenolic resin via ring-opening reaction with acrylic acid and with aqueous solu... New water soluble and photocrosslinkable prepolymers containing acrylate and quaternary ammonium salt groups were synthesized from epoxy phenolic resin via ring-opening reaction with acrylic acid and with aqueous solution of triethylamine hydrochloride successively. The second reaction needs no phase transfer catalyst to accelerate, since the product formed can act as a phase transfer catalyst. The prepolymer obtained contains both photocrosslinkable acrylate groups and hydrophilic quaternary ammonium salt groups. Optimum conditions for these reactions were studied. The photosensitivity of the prepolymer was also investigated. The effects of different photoinitiators, different crosslinkable diluent monomers and amine accelerator on the photosensitivity of the prepolymer were compared. The photoinitiator of hydrogen abstraction type is still effective without using amine or alcohol as accelerator, because the prepolymer contains a H beside the OH groups formed in the ring-opening reactions. 展开更多
关键词 photosensitive polymer PHOTOCROSSLINKING water soluble polymer epoxy phenolic resin quaternary ammonium salt
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Flotation and adsorption of quaternary ammonium salts collectors on kaolinite of different particle size 被引量:6
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作者 Jiang Hao Liu Guorong +4 位作者 Hu Yuehua Xu Longhua Yu Yawen Xie Zhen Chen Haochuan 《International Journal of Mining Science and Technology》 SCIE EI 2013年第2期255-259,共5页
The flotation behaviors of decyltrimethylammonium (103C), dodecyltrimethylammonium chloride (DTAC), tetradecyltrimethylammonium chloride (TTAC) and cetyltrimethylammonium chloride (CTAC) on kaolinite of different part... The flotation behaviors of decyltrimethylammonium (103C), dodecyltrimethylammonium chloride (DTAC), tetradecyltrimethylammonium chloride (TTAC) and cetyltrimethylammonium chloride (CTAC) on kaolinite of different particle size fraction were studied. The adsorbed amount and adsorption isotherms of collectors on kaolinite were determined for painstaking investigation into the adsorption of quaternary amines at kaolinite-water interface by ultraviolet spectrophotometer methods. The flotation results show that the flotation recovery of kaolinite of different particle fraction increases with an increase in pH when 103C, DTAC, TTAC and CTAC are used as collectors. As the concentration of collectors increases, the flotation recovery increases. Particle size of kaolinite has a strong effect on flotation. The flotation recovery of fine kaolinite decreases with the carbon chain of quaternary ammonium salts collectors increasing, while coarse kaolinite is on the contrary. The adsorbed amount tests and adsorption isotherms show that adsorbed amount increases when the particle size of kaolinite increases or when the carbon chain length of quaternary ammonium salts increases. Within the range of flotation collector concentration, the longer the hydrocarbon chain, the more probable to be absolutely adsorbed by fine kaolinite particles and then the lower the collector concentration in the bulk, which leds to lower flotation recovery. 展开更多
关键词 Kaolinite Particle size quaternary ammonium salts Flotation Adsorption
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QSAR Modeling of Toxicity of Quaternary Ammonium Compounds to Chlorella pyrenoidosa Using 2D and 3D Descriptors 被引量:1
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作者 金浩 花书贵 +1 位作者 冯明宝 陈磊 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2015年第12期1793-1802,共10页
To investigate the relationships between structures and toxicities of 13 quaternary ammonium compounds (QACs) to Chlorella pyrenoidosa, 2D- and 3D-QSAR models were built. The 2D-QSAR model included two parameters: ... To investigate the relationships between structures and toxicities of 13 quaternary ammonium compounds (QACs) to Chlorella pyrenoidosa, 2D- and 3D-QSAR models were built. The 2D-QSAR model included two parameters: averaged polarizability (a) and total connectivity (Tcon). Furthermore, 3D-QSAR models were proposed by using comparative molecular field analysis (CoMFA) and molecular similarity index analysis (CoMSIA). All these models were robust and predictive. To our interest, 3D-QSAR model suggested that the hydrophobieity of substituents was the dominating factor for the toxicities, electrostatic effect was the secondly important, and steric field gave the least contribution. Comparatively, the predictive ability of 3D-QSAR model is slightly more advantageous than that of 2D-QSAR. They can be used complementally in the toxicity description of this kind of compounds. 展开更多
关键词 QSAR quaternary ammonium compounds TOXICITY COMSIA COMFA
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Synthesis and Structure of Ag(I)- Containing Coordination Polymers Based on Quaternary Ammonium Template Reagent 被引量:1
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作者 柯子厚 陈之荣 +3 位作者 李浩宏 黄长沧 肖光参 赵斌 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2005年第5期509-512,489,共5页
A novel coordination polymer [(C8H20N)(Ag2I3)]n ([C8H20N]+ = tetraethyl ammo- nium (TEA)) was synthesized by the reaction of AgI and C8H20NI at room temperature with pH = 6.5, and structurally characterized by means o... A novel coordination polymer [(C8H20N)(Ag2I3)]n ([C8H20N]+ = tetraethyl ammo- nium (TEA)) was synthesized by the reaction of AgI and C8H20NI at room temperature with pH = 6.5, and structurally characterized by means of X-ray single-crystal diffraction. It crystallizes in orthorhombic, space group Pna21 with a = 7.3323(9), b = 18.250(2), c =12.5294(15) ?, C6.33H16.16NAg2I3, Mr = 702.76, V = 1676.6(4) ?3, Z = 4, Dc = 2.784 g/cm3, F(000) = 1256.6, μ(MoKα) = 7.828 mm-1, the final R = 0.0529 and wR = 0.1586 for 1189 observed reflections with I > 2σ(I). X-ray analysis shows that the [Ag2I3]n- chain is built up by AgI4 tetrahedron and in combination with quaternary ammonium cations ([C8H20N]+) by static attractive forces to form the so-called organic-inorganic hybrid material. 展开更多
关键词 coordination polymers template synthesis IODIDE quaternary ammonium
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Effect of Electrolyte Impurities within Starch on the Adhesion of Quaternary Ammonium Starch to Fibers 被引量:2
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作者 祝志峰 程哲琼 郭腊梅 《Journal of Donghua University(English Edition)》 EI CAS 2008年第3期328-333,共6页
Influences of some electrolyte impurities within starch and starch cationization on the adhesion of quaternary ammonium cornstarch to cotton and polyester fibers were investigated. The electrolytes considered incl... Influences of some electrolyte impurities within starch and starch cationization on the adhesion of quaternary ammonium cornstarch to cotton and polyester fibers were investigated. The electrolytes considered included NaCI, Na2SO4, NaH2PO4 and Na2HPO4. The adhesion to fibers was evaluated in terms of maximum strength and work-to-break of the roving sized with the starch pastes containing electrolytes. It was found that the cationization showed a positive effect on the adhesion to both fibers whereas the electrolytes gave an adverse effect and reduced the adhesion. The adverse effect depends on the type and amount of electrolytes. The influence of electrolytes on the adhesion can be ranked in a series of NaH2PO4〉 Na2 HPO4〉 Na2SO4 〉 NaCl. The adhesion enhances as the modification extent increases and the electrolyte content decreases. Furthermore, the adverse effect can be compensated by the positive effect of the starch modification even at a low modification extent. If the electrolytes are fully eliminated, the cationic starch can increase the adhesion strength by more than 10% for both fibers. 展开更多
关键词 ADHESION quaternary ammonium starch ELECTROLYTE FIBER
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Adsorption of Quaternary Ammonium Compounds onto Activated Sludge 被引量:1
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作者 Rong Ren Dongfang Liu +2 位作者 Kexun Li Jie Sun Chong Zhang 《Journal of Water Resource and Protection》 2011年第2期105-113,共9页
The performance of activated sludge in the removal of tetradecyl benzyl dimethyl ammonium chloride (C14BDMA) by adsorption from aqueous solution was investigated with different PH, contact time, ionic strength and tem... The performance of activated sludge in the removal of tetradecyl benzyl dimethyl ammonium chloride (C14BDMA) by adsorption from aqueous solution was investigated with different PH, contact time, ionic strength and temperature. Equilibrium was achieved within 2 h of contact time. The adsorption capacity increased largely with increasing solution pH and remained constant above pH 9. The ionic strength had a negative effect on C14BDMA removal. The adsorption isotherms were analyzed by Langmuir and Freundlich isotherm models, and equilibrium partitioning data was described well by both models. Kinetics data was best described by the pseudo second-order model. Experimental results indicated that the adsorption was favorable at lower temperatures. Thermodynamic parameters, including the Gibbs free energy (ΔG0), enthalpy (ΔH0), and entropy (ΔS0), were also calculated. These parameters indicated that adsorption of C14BDMA onto activated sludge was feasible, spontaneous and exothermic in the temperature range of 15-35℃. The activated sludge was shown to be an effective adsorbent for C14BDMA. 展开更多
关键词 Activated SLUDGE ADSORPTION Kinetics quaternary ammonium Compounds THERMODYNAMICS Analysis
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Aluminum-silicates flotation with quaternary ammonium salts 被引量:7
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作者 王毓华 胡岳华 陈湘清 《中国有色金属学会会刊:英文版》 CSCD 2003年第3期715-719,共5页
The zeta potential measurements show that the flotation separation of diaspore from kaolinite, illite and pyrophyllite could be achieved in the range of pH 46.5 with cationic collectors. A special quaternary ammonium ... The zeta potential measurements show that the flotation separation of diaspore from kaolinite, illite and pyrophyllite could be achieved in the range of pH 46.5 with cationic collectors. A special quaternary ammonium salts(DTAL) shows better selectivity than that the dodecyl amine(DDA) does for the flotation of three silicates. The closed circuit flotation results show that the reverse flotation de silicate can be achieved with DTAL as collector, a new inorganic reagent(SFL) as depressant and MIBC as frother to obtain a bauxite concentrate m (Al 2O 3)/ m (SiO 2) >10, Al 2O 3 recovery>86%). 展开更多
关键词 铝土矿 选矿 浮选 铝硅酸盐 浮选药剂 铵盐
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Preparation of spiro-type quaternary ammonium salt via economical and efficient synthetic route as electrolyte for electric double-layer capacitor 被引量:4
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作者 周宏明 孙文佼 李荐 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第7期2435-2439,共5页
A spiro-type quaternary ammonium salt, spiro-(1,1′)-bipyrrolidinium tetrafluoroborate(SBP-BF4) was successfully prepared by an economical and efficient three-step process comprising the cyclization reaction of 1,4-di... A spiro-type quaternary ammonium salt, spiro-(1,1′)-bipyrrolidinium tetrafluoroborate(SBP-BF4) was successfully prepared by an economical and efficient three-step process comprising the cyclization reaction of 1,4-dibromobutane and pyrrolidine, and subsequent ion exchange pathway with KOH followed by neutralization reaction via HBF4 in the system of ethanol solution. 1H NMR, 13 C NMR, FI-IR and XPS analyses showed the structure of SBP-BF4. The as-obtained SBP-BF4 was dissolved in AN and used as the electrolyte for supercapacitor. Electrochemical measurements demonstrate that, compared with commercial electrolyte TEMA-BF4/AN, SBP-BF4/AN exhibits high ionic conductivity, lower resistance and improved cycling performance, which is due to its smaller ion size and stable symmetry structure. 展开更多
关键词 spiro-type quaternary ammonium salt synthesis electrolyte electric double-layer capacitor
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Preparation and Properties of Poly(amidoamine) Dendrimer/Quaternary Ammonium Chitosan Hydrogels 被引量:2
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作者 何广华 KONG Yahui +4 位作者 郑化 KE Wanwan CHEN Xiang YIN Yihua YI Ying 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2018年第3期736-743,共8页
A novel quaternary ammonium chitosan hydrogel modified by poly(amidoamine)(PAMAM) dendrimer was prepared by using glutaraldehyde as a cross-linker. The hydrogel was characterized by Fourier transform infrared spec... A novel quaternary ammonium chitosan hydrogel modified by poly(amidoamine)(PAMAM) dendrimer was prepared by using glutaraldehyde as a cross-linker. The hydrogel was characterized by Fourier transform infrared spectroscopy(FTIR) and scanning electron microscopy(SEM). The results confirmed its highly porous three-dimensional network structure. The swelling test of hydrogel proved that it had excellent swelling and p H-sensitive properties. The increasing PAMAM content or quaternization degree led to the increase in swelling properties. And the hydrogel with lower cross-linking agent concentration or quaternary ammonium chitosan concentration exhibited better swelling properties. The antibacterial results indicated that with the increase in the PAMAM content, quaternary ammonium chitosan concentration or cross-linking agent concentration, the hydrogels showed better antibacterial activities against both Staphylococcus aureus(S. aureus) and Escherichia coli(E. coli). Thus, the hydrogel could serve as a promising antibacterial material in the future. 展开更多
关键词 hydrogel quaternary ammonium chitosan poly(amidoamine) dendrimer antibacterial activity
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