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Comparative Study on Properties of PBAT/PBSA Film Modified by a Multi-Functional Epoxide Chain Extender or Benzoyl Peroxide
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作者 Yanfeng Zhu Huidong Shi +3 位作者 Qing Ju Dong Zhao Yucai Shen Tingwei Wang 《Journal of Renewable Materials》 SCIE EI 2023年第3期1303-1319,共17页
Poly(butylene adipate-co-terephthalate)(PBAT)and poly(butylene succinate-co-adipate)(PBSA)blend films were prepared with different contents of a multifunctional epoxide chain extender Joncryl ADR-4468(ADR)or benzoyl p... Poly(butylene adipate-co-terephthalate)(PBAT)and poly(butylene succinate-co-adipate)(PBSA)blend films were prepared with different contents of a multifunctional epoxide chain extender Joncryl ADR-4468(ADR)or benzoyl peroxide(BPO).The long-chain-branching(LCB)introduced by ADR and branched/crosslinked entanglement induced by BPO increased melt elasticity,viscosity and compatibility,as indicated by thermal properties,rheological and morphological analyses.It was found that the elongation at break and the tensile strength were significantly improved,due to the enhancement of compatibility and the interfacial adhesion by the incorporation of ADR or BPO.The best mechanical properties were obtained in PBAT/PBSA/ADR(60/40/0.3)(A4T6A_(0.3))and PBAT/PBSA/BPO(60/40/0.9)(A4T6B_(0.9))films,respectively.With the rapid initiation of chain growth by BPO,it has significantly improved the transparency of the film.ADR and BPO can be used interchangeably in improving the comprehensive properties of PBAT/PBSA films,and it would provide more strategies for developing biodegradable materials for various applications. 展开更多
关键词 PBAT PBSA chain extend in-situ compatibilization
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Cryopreservation of cynomolgus monkey (Macacafascicularis)spermatozoa in a chemically defined extender 被引量:11
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作者 Ya-HuiLi Ke-JunCai +5 位作者 LeiSu MoGuan Xie-ChaoHe HongWang AndrasKovacs Wei-ZhiJi 《Asian Journal of Andrology》 SCIE CAS CSCD 2005年第2期139-144,共6页
Aim:To establish a method for cynomolgus monkey sperm cryopreservation in a chemically defined extender. Methods:Semen samples were collected by electro-ejaculation from four sexually mature male cynomolgus monkeys. T... Aim:To establish a method for cynomolgus monkey sperm cryopreservation in a chemically defined extender. Methods:Semen samples were collected by electro-ejaculation from four sexually mature male cynomolgus monkeys. The spermatozoa were frozen in straws by liquid nitrogen vapor using egg-yolk-free Tes-Tris (mTTE) synthetic extender and glycerol as cryoprotectant.The effects of glycerol concentration (1%,3 %,5 %,10 % and 15 % [v/v]) and its equilibration time (10 min,30 min,60 min and 90 min) on post-thaw spermatozoa were examined by sperm motility and sperm head membrane integrity.Results:The post-thaw motility and head membrane integrity of spermatozoa were significantly higher (P<0.05) for 5 % glycerol (42.95±2.55 and 50.39±2.42,respectively) than those of the other groups (1%:19.19±3.22 and 24.84±3.64;3 %:34.23±3.43 and 41.37±3.42;10 %: 15.68±2.36 and 21.39±3.14;15 %:7.47±1.44 and 12.90±2.18).The parameters for 30 min equilibration (42.95±2.55 and 50.39±2.42) were better (P<0.05) than those of the other groups (10 min:31.33±3.06 and 38. 98±3.31;60 min:32.49±3.86 and 40.01±4.18;90 min:31.16±3.66 and 38.30±3.78).Five percent glycerol and 30 min equilibration yielded the highest post-thaw sperm motility and head membrane integrity.Conclusion: Cynomolgus monkey spermatozoa can be successfully cryopreserved in a chemically defined extender,which is related to the concentration and the equilibration time of glycerol. 展开更多
关键词 CRYOPRESERVATION MACACAFASCICULARIS chemically defined extender GLYCEROL
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Synthesis and characterization of yellow water-borne polyurethane using a diol colorant as extender 被引量:5
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作者 Zhang, He Zhang, Xing Yuan +1 位作者 Dai, Jia Bing Li, Wei Hu 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第2期143-145,共3页
A novel and facile method toward a series of yellow water-borne polyurethane was developed by using an intrinsically colored diol in this paper.The yellow aqueous dispersion PCLD-HENA-PU was synthesized based on isoph... A novel and facile method toward a series of yellow water-borne polyurethane was developed by using an intrinsically colored diol in this paper.The yellow aqueous dispersion PCLD-HENA-PU was synthesized based on isophorone diisocyanate(IPDI), polycaprolactonediol(PCLD) and 2,2-dimethylol propionic acid(DMPA) using a yellow diol N,N-bis(2-hydroxyethyl)-4-nitroaniline (HENA) as a chain extender.Due to the complete reaction of OH group in colorant HENA with NCO group in diisocyanate,a series of stable yellow p... 展开更多
关键词 Colored diol extender Polycaprolactonediol N N-bis(2-hydroxyethyl)-4-nitroaniline Yellow polyurethane
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Silicone Chain Extender for Recycled Polyethylene-terephthalate with Higher Flexibility 被引量:1
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作者 王莉 HAO Tonghui +2 位作者 HUANG Long HUANG Ji 黄容华 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2019年第5期1228-1232,共5页
To decrease the modulus and increase the mechanical properties of recycled PET by introducing the flexible segments, the recycled polyethylene-terephthalate(PET) was modified by the chain extender produced with 2, 4, ... To decrease the modulus and increase the mechanical properties of recycled PET by introducing the flexible segments, the recycled polyethylene-terephthalate(PET) was modified by the chain extender produced with 2, 4, 6, 8-tetramethyl-2, 4, 6, 8-tetra(2, 3-epoxypropoxy) propylcyclotetrasiloxane by the hydrosilylation reaction. Different percentages of chain extender were used in order to investigate the effect of chain extender content on the modulus of PET. The dynamic mechanical analysis was performed on PET samples, which showed that Tg of PET was firstly raised by the addition of chain extender and then decreased. Small amplitude shearing test performed on PET samples confirmed that the addition of the flexible segments could remarkably decrease the modulus of PET, which would be helpful for the extrusion process. The entanglements from branches were also influenced by the addition of extender. 展开更多
关键词 PET chain extender SILICONE FLEXIBILITY BRANCHES
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Effects on the quality of frozen-thawed alpaca(Lama pacos)semen using two different cryoprotectants and extenders 被引量:1
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作者 AlexeiSantiani WilfredoHuanca +3 位作者 RómuloSapana TeodosioHuanca NéstorSepúlveda RaúlSánchez 《Asian Journal of Andrology》 SCIE CAS CSCD 2005年第3期303-309, ,共7页
Aim: To evaluate two extenders and two cryoprotectant agents (CPA) for alpaca semen cryopreservation. Methods: Semen samples were obtained from four adult alpacas (Lama pacos) and frozen using extender Ⅰ (TRIS... Aim: To evaluate two extenders and two cryoprotectant agents (CPA) for alpaca semen cryopreservation. Methods: Semen samples were obtained from four adult alpacas (Lama pacos) and frozen using extender Ⅰ (TRIS, citrate, egg yolk and glucose) or extender Ⅱ (skim milk, egg yolk and fructose), each containing either glycerol (G) or ethylene glycol (EG) as CPA. Consequently, four groups were formed: 1) extender Ⅰ-G; 2) extender Ⅰ-EG; 3) extender Ⅱ-G; and 4) extender Ⅱ-EG. Semen was diluted in a two-step process: for cooling to 5 ℃ (extenders without CPA), and for freezing (extenders with CPA). Viability and acrosome integrity were assessed using trypan blue and Giemsa stains. Results: When compared, the motility after thawing was higher (P 〈 0.05) in groups Ⅱ-EG (20.0 %±6.7 %) and Ⅱ-G (15.3 %±4.1%) than that in groups Ⅰ-G (4.0 %±1.1%) and Ⅰ-EG (1.0 %±1.4 %). Viable spermatozoa with intact acrosomes in groups Ⅱ-EG (18.7 %±2.9 %) and Ⅱ-G (12.7 %±5.9 %) were higher than that in groups Ⅰ-G (5.7 %±1.5 %) and Ⅰ-EG (4.0 %±1.0 %). Conclusion: The skim milk- and egg yolk-based extenders containing ethylene glycol or glycerol to freeze alpaca semen seems to promote the survival of more sperm cells with intact acrosomes than the other extenders. (Asian J Androl 2005 Sep; 7: 303-309) 展开更多
关键词 cryopreservation glycerol ethylene glycol extenderS alpaca spermatozoa
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Effect of Semen Extender and Storage Temperature on Motility of Ram Spermatozoa 被引量:2
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作者 Mohan Acharya Joan M. Burke Rick W. Rorie 《Advances in Reproductive Sciences》 2020年第1期14-30,共17页
Cryopreservation of ram semen results in low post-thaw survival. Thus, studies were conducted to optimize liquid-storage of chilled semen. In Experiment 1, semen collected from rams (n = 5) was extended using either m... Cryopreservation of ram semen results in low post-thaw survival. Thus, studies were conducted to optimize liquid-storage of chilled semen. In Experiment 1, semen collected from rams (n = 5) was extended using either milk, TRIS (tris[Hydroxymethyl]aminomethane), TEST (N-Tris (hydroxymethyl)-methyl-2-aminoethane sulfonic acid), or CJ-2 (choline-based extender) and stored at either 4℃ and 15℃. All extenders were supplemented with 5% (v/v) egg yolk. In Experiment 2, semen collected from 9 rams was distributed across TRIS or milk extenders supplemented with 5% or 20% (v/v) egg yolk, and 0 or 1% ethylene glycol (EG), during storage for 72 hours at 4℃. The effect of penicillamine, hypotaurine, and epinephrine (PHE) on motility parameters was also evaluated following storage. In Experiment 1, most of the sperm motility parameters were higher after extension, and storage at 4℃ compared with 15℃ (P P in vivo sperm viability and conception rates when using extended, stored semen for artificial insemination of ewes. 展开更多
关键词 SEMEN extenderS RAM SEMEN Liquid STORAGE SHEEP
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Performance of Local Clay-Titanium Dioxide Core-Shell Extender Pigments in Alkyd Paints 被引量:1
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作者 C. M. Ewulonu I. O. Igwe G. N. Onyeagoro 《Advances in Nanoparticles》 2016年第1期90-102,共13页
The performance of local clay-titanium dioxide core-shell extender pigments in alkyd paints has been studied. The physico-mechanical properties of the prepared alkyd paints were evaluated according to ASTM measurement... The performance of local clay-titanium dioxide core-shell extender pigments in alkyd paints has been studied. The physico-mechanical properties of the prepared alkyd paints were evaluated according to ASTM measurements. The effects of various environmental and corrosive factors on the paints were also studied. The study showed that the alkyd paint samples formulated using the core-shell pigments generally had low specific gravity (1.30 – 1.38), an indication that more of the core-shell pigments can be incorporated into the alkyd paints with considerable cost savings. The dry film thicknesses of the paint samples falls within 0.24 - 0.39 mm, suggesting that the samples will perform well as anticorrosive coatings and their adhesion properties are generally good, showing that they can withstand abrasive and corrosive agents. The core-shell extender pigments formulated paint samples were observed to exhibit the best dust-free, tack-free, and through dry times compared to TiO<sub>2</sub> paint formulation. The formulated paint samples generally performed well on exposure to rain and sunlight as well as in distilled water, 2% Na<sub>2</sub>CO<sub>3</sub>, and 2% H<sub>2</sub>SO<sub>4</sub> with only TiO<sub>2</sub> paint formulation exhibiting rust. The good paint performance characteristics obtainable with the core-shell extender pigments are enough evidence to justify their utilization in the surface coatings industry. The performances of these core-shell extender pigments in alkyd paints have shown that they combine the properties of both the clays and titanium dioxide, and have the potential to overcome their disadvantages. 展开更多
关键词 CLAY Titanium Dioxide extender Pigments NANOPARTICLES Core-Shell Pigments Alkyd Paints
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Preservability of rabbit semen after chilled storage in tris based extender enriched with different concentrations of Propolis ethanolic extract (PEE)
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作者 Islam El-Sayed El-Seadawy Walid Said El-Nattat +3 位作者 Magda Mohamed El-Tohamy Samy Ali Hussein Aziza Yakot Abdelfattah El-Senosy Ahmed Said Hussein 《Asian pacific Journal of Reproduction》 2017年第2期68-76,共9页
Objective:To maintain semen quality of male rabbits during chilled storage by enrichment the tris based diluent with different concentrations of propolis ethanolic extracts.Methods: Total phenolic and total flavonoid ... Objective:To maintain semen quality of male rabbits during chilled storage by enrichment the tris based diluent with different concentrations of propolis ethanolic extracts.Methods: Total phenolic and total flavonoid contents, as well as antioxidant activity was determined in propolis ethanolic extract (PEE). The extract was analysed by HPLC for separation and identification of target metabolites. Semen was collected from 10 rabbit bucks, pooled, then divided into five aliquots (each of 500 μL) and diluted each in 5 mL Tris-citric acid-glucose-egg yolk extender (TCGY). The 1st aliquot served as control while PEE was added at concentration of 0.8, 1.2, 1.6 and 2.0 mg/5 mL tris extender in the aliquot 2, 3, 4 and 5 respectively. Diluted semen samples were subjected to cooling at 4℃ for 72 h. Sperm motility, sperm viability, sperm abnormality, sperm membrane integrity and acrosome integrity were evaluated in chilled semen allover the chilling period.Results:The resluts revealed presence of a considerable amount of total phenolic compounds (98.67 mg GAE/g extract) and total flavonoids (70.16 mg CE/g extract) which were parallel to an antioxidant activity assessed as ABTS, DPPH and FRAP (198.65, 180.18 and 306.17 mM TE/g extract respectively). The dominant phenolic acid was chlorogenic acids (3.959 mg/g extract). Other compounds were found in less amounts rosmarinic acid (3.959 mg/g extract), myrcetin (1.946 mg/g extract), kaempferol (1.089 mg/g extract) and apeginin-7-glucoside (1.113 mg/g extract). Obtained results clearly demonstrated that the addition of (1.2-1.6) mg PEE in the chilled extended rabbit semen proved to be beneficial for maintaining semen characteristics compared to control and the addition of 0.8 and 2 mg PEE.Conclusions: The enrichment of rabbit semen tris-basic extender with (1.2-1.6) mg PEE/5 mL tris-extender (as the best and safe concentrations) maintain the sperm characteristics in good condition all over 72 h of chilling. 展开更多
关键词 Male rabbits SEMEN extender PROPOLIS extract ANTIOXIDANTS HPLC
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Study on Cryopreservative Effect of Three Penetrating Cryoprotectants with Three Kinds of Extenders on Rabbit Spermatozoa
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作者 ZHANGGui-xue LIXiao-juan 《Journal of Northeast Agricultural University(English Edition)》 CAS 2001年第1期30-36,共7页
Glycerol,dimethyl suffixod (DMSO) and acetamide were adopted to verify the cryoprotective ability of penetrating cryoprotectants with three kinds of extenders for rabbit sperm. Three extenders (A,B and C) and three le... Glycerol,dimethyl suffixod (DMSO) and acetamide were adopted to verify the cryoprotective ability of penetrating cryoprotectants with three kinds of extenders for rabbit sperm. Three extenders (A,B and C) and three level of the final concentrations of glycerol and DMSO (2%, 3% and 4% ),and acetamide 2%,4% and 5% were used with Extender A, 4% glycerol had better cryoprotective effect for rabbit sperm motility and 5% acetamide was better with Extender C. 4% acetamide was better in being combined with Extender A for sperm acrosome integrity ratio,5% acetamide was better with Extender B and 2% acetamide was better with Extende C. With extender A,there was not difference among three penetrating cryoprotectants for plasma membrane integrity. With Extender B, 3% glycerol was better than 4% acetamide for plasma membrane in- tegrity,and 3% glycerol with Extender C was better than 2% - 4% DMSO and 2% acetamide. 展开更多
关键词 rabbit spermatozoa cryopreservation extender CRYOPROTECTANT
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Dietary selenium supplementation, clarified egg yolk extender and slow cooling improve cryopreserved sperm characteristics of Saanen buck
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作者 Kambulu Lukusa Abubeker Hassen Khoboso C.Lehloenya 《Asian pacific Journal of Reproduction》 2021年第1期43-48,共6页
Objective:To evaluate the effect of cooling rates,selenium supplementation,and three semen extenders on cooled and frozen-thawed Saanen buck sperm.Methods:Twenty Saanen bucks were divided into two groups:the selenium ... Objective:To evaluate the effect of cooling rates,selenium supplementation,and three semen extenders on cooled and frozen-thawed Saanen buck sperm.Methods:Twenty Saanen bucks were divided into two groups:the selenium supplemented group and the control group.Ejaculates were collected once weekly by artificial vagina.The first experiment examined the effects of cooling rates and selenium supplementation on semen characteristics of Saanen bucks.Pooled semen was diluted with triladyl extender and split into two aliquots for slow and fast cooling.The second experiment explored the effect of selenium supplementation and semen extenders on post-cryopreserved sperm quality.Ejaculates from each group were divided into three aliquots and diluted with three extenders(i.e.clarified egg-yolk,whole egg yolk,Tris without egg-yolk extenders).All samples were cooled for 2 h at 4℃and frozen at-196℃for 24 h.The sperm characteristics such as sperm motility,acrosome integrity,normal morphology,and viability were evaluated by using a phase-contrast microscope.Results:In the first experiment,all sperm characteristics were significantly increased in selenium supplemented samples when slow cooling was used(P<0.05).In the second experiment,in cooled semen,sperm motility and viability were significantly increased in both clarified egg yolk and Tris without egg yolk extenders in selenium supplemented samples as compared with whole egg yolk extender,respectively(P<0.05).After freezing-thawing,all sperm parameters of selenium supplemented samples in clarified egg yolk extender were significantly greater than those in Tris without egg yolk extender(P<0.05).However,normal morphology and acrosome integrity of selenium supplemented samples in whole egg yolk extender were similar to those of selenium supplemented samples in clarified egg yolk extender.Conclusions:The characteristics of cooled and post-cryopreserved sperm are greater when clarified egg yolk extender is used in semen from selenium supplemented bucks. 展开更多
关键词 extenderS Sperm characteristics CRYOPRESERVATION Selenium Cooling rates
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Anti-wrinkle Finishing of Cotton Fabrics with Pyromellitic Acid Enhanced by Polyol Extenders
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作者 齐欢 孟露杰 +4 位作者 林晓芳 许婉婉 陈杨轶 张初阳 邱夷平 《Journal of Donghua University(English Edition)》 CAS 2022年第6期533-541,共9页
Pyromellitic acid(PMA)has been employed for formaldehyde-free anti-wrinkle finishing on cotton fabrics for its low damage to fibers and absence of phosphorus-containing catalysts.However,the wrinkle resistance perform... Pyromellitic acid(PMA)has been employed for formaldehyde-free anti-wrinkle finishing on cotton fabrics for its low damage to fibers and absence of phosphorus-containing catalysts.However,the wrinkle resistance performance of fabrics failed to meet the application expectation.In this work,the polyol extenders were introduced into PMA cross-linked cellulose for further improving fabric resilience by a two-step dipping-squeezing-curing method.Eleven polyols were employed as the chain extenders for PMA anti-wrinkle finishing on fabrics,among which sorbitol presented the best chain-spreading effect on wrinkle resistance.After screening the process parameters,the optimum process was obtained as follows.The dosage ratio of PMA to sorbitol was 1∶1,the curing condition was 150-160℃ for 2-3 min.Scanning electron microscopy(SEM),thermogravimetric analysis(TGA)and Fourier transform infrared(FTIR)spectroscopy were employed to characterize the fiber changes during the process.The results showed that the sorbitol incorporation could facilitate the remelting and redissolution of PMA on fiber surface.During the curing process,sorbitol could form ester linkages between PMA molecules and improve the fiber resilience.The treated samples presented excellent washing durability,and the wrinkle recovery angle A_(w)was still 265.1°after 10 washes,which was close to that of 1,2,3,4-butane tetracarboxylic acid(BTCA)but with lower tearing load loss.The results provide new insights for the application of PMA in formaldehyde-free anti-wrinkle finishing on cotton fabrics. 展开更多
关键词 pyromellitic acid polyol extender anti-wrinkle finishing ESTERIFICATION extended crosslinking
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Characterization and Utilization of Eziulo Clay as an Extender in Emulsion Paint Formulations
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作者 Isaac O. Igwe Gift Osuoha Chinedu Nwapa 《Journal of Minerals and Materials Characterization and Engineering》 2017年第4期174-184,共11页
A series of emulsion paint samples were prepared using Eziulo clay as an extender, commercial whiting, and titanium dioxide (TiO2). The clay that was calcined at 850oC and sieved to three particle sizes (0.075, 0.100 ... A series of emulsion paint samples were prepared using Eziulo clay as an extender, commercial whiting, and titanium dioxide (TiO2). The clay that was calcined at 850oC and sieved to three particle sizes (0.075, 0.100 and 0.150 mm) was incorporated into emulsion paints at varying amounts ranging from 5% - 32% of the total extender and pigment in the paints. Poly (vinyl acetate) was used as the binder while distilled water served as the solvent. The Eziulo clay which consisted mostly of silica (63.30%), alumina (19.40%), and iron (III) oxide (2.10%) had the following properties: pH (6.67), specific gravity (2.47) and oil absorption (34.30 g/100 g clay). The colour and solubility of the clay in dilute hydrochloric acid, acetic acid, sodium chloride solution, methanol and distilled water were generally unaffected either in the cold or when heated expect for the slight solubility observed in methanol. The clay formulated paint samples exhibited higher viscosity (7.0 - 7.80 poise) than the paint sample without Eziulo clay (6.60 poise). Conversely, the pH and specific gravity of the paint sample without Eziulo clay were higher than those of paint sample containing the clay. The surface and hard dry times of the formulated paint samples were greater than that of the paint sample without Eziulo clay. The determined surface dry times were within the range, 16 - 18 min, irrespective of clay content and particle size. The hard dry times of the formulated paint samples were found to reverse with increases in clay content. The paint dry film flexibility was unaffected by the incorporation of clay, irrespective of the amount and clay particle size. The emulsion paint dry films exhibited decreases in film adhesion to substrates with increases in clay content, and increases in film adhesion with increases in clay particle size. The paint dry films did not exhibit any chalking tendency, were resistant to fungal attack, and passed the water drop test. The present study has demonstrated the utility of Eziulo clay in emulsion paint formulations which should justify its use in the surface coatings industry. 展开更多
关键词 extender EMULSION PAINT Eziulo CLAY DRYING Properties Titanium Dioxide CLAY Particle Size CHARACTERIZATION
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Effects of Bifunctional Chain Extender on the Crystallinity and Thermal Stability of PET
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作者 Bo Liu Qianwei Xu 《Journal of Materials Science and Chemical Engineering》 2013年第6期9-15,共7页
Effects of bifunctional chain extender on the crystallinity and the thermal stability of PET were studied in this work. Results of Infrared substractive spectrum indicated that one oxazoline ring of 2,2’-bis(2-oxazol... Effects of bifunctional chain extender on the crystallinity and the thermal stability of PET were studied in this work. Results of Infrared substractive spectrum indicated that one oxazoline ring of 2,2’-bis(2-oxazoline) (BOZ) reacted with one carboxyl in PET to generate a blocked PET chain with an oxazoline ring, which then reacted with one carboxyl in second PET to form an extended chain. The intrinsic viscosity (IV) of extended PET would increase from 0.61 of initial PET to 0.80 when the addition of BOZ was 0.52 wt%. Furthermore, when BOZ was used with hydroxyl-addition-type chain extender 2,2’-(1,4-phenyl)bis(4H-3,1-benzoxazin-4-one) (BNZ) or chain end modifier phthalic anhydride (PA), IV of chain extended PET would be 0.83 and 0.97 respectively. DSC results showed that chain extending would result in a decrease in crystallinity of PET. Comparing with initial PET, the intrinsic viscosity loss of the chain extended products would be smaller after multi-melting processing. 展开更多
关键词 Poly(Ethylene Terephthalate) Chain extender Infrared Substractive Spectrum INTRINSIC Viscosity
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Extender Properties of Some Nigerian Clays
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作者 Iheoma C. Chukwujike Isaac O. Igwe 《Journal of Minerals and Materials Characterization and Engineering》 2016年第5期279-291,共14页
The extender properties of some Nigeria clays have been studied. The local clays were characterized using X-ray fluorescence and scanning electron microscope. The physico-chemical properties of the clays were evaluate... The extender properties of some Nigeria clays have been studied. The local clays were characterized using X-ray fluorescence and scanning electron microscope. The physico-chemical properties of the clays were evaluated using ASTM standards. The physico-chemical characterization of the local clays gave the following results: specific gravity (2.54 and 2.49), oil absorption (51.0 and 59.0 g/100g), refractive index (1.7 and 2.0) and pH (5.1 and 4.8) for Nsu and Ihitte-Uboma clays respectively. Compositional analysis showed that the clays consisted predominantly of silica (SiO2) and aluminium oxide (Al2O3) in high proportions with the other constituents present in very small proportions. The clays were stable to heat and insoluble in toluene, methanol, ethanol, 2-propanol, chloroform and hydrochloric acidexcept for their slight solubility in acetic acid. The colour of the clays was not affected in cold or when heated except for slight colour change observed in the presence of hydrochloric acid when heated. The particle morphology of the clays indicated the presence of sub-angular platelet of varying sizes. The optimum calcination temperature of the clays was determined to be 850°C for use in oil-based paints. The clays can be used in gloss paints, rubber and plastic composites and as an adsorbent with improved properties. 展开更多
关键词 CLAY extender Pigments Calcination Temperature Titanium Dioxide CHARACTERIZATION
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Laboratory Evaluation of Asphalt Containing Recycled Plastic as a Bitumen Extender and Modifier
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作者 Greg White Connor Magee 《Journal of Traffic and Transportation Engineering》 2019年第5期218-235,共18页
Recent interest in recycling and reuse of waste plastic has resulted in a dramatic increase in the evaluation of waste plastic as an extender and/or modifier of bituminous binder for asphalt production. Although signi... Recent interest in recycling and reuse of waste plastic has resulted in a dramatic increase in the evaluation of waste plastic as an extender and/or modifier of bituminous binder for asphalt production. Although significant field trials of waste plastic modified asphalt have been reported in Australia since 2017, no laboratory evaluation of the effects of these products on the engineering properties of binder and asphalt has been published. In this research, two commercially available recycled waste plastic products were evaluated in the laboratory. One product is intended to be plastomeric while the other is intended to be elastomeric in nature. Compared to unmodified viscosity grade bitumen and acid modified multigrade, the recycled plastic products increased the viscosity and softening temperature of the binder and introduced significant elastic recovery. Following dry-mixing into asphalt, the recycled plastic products were associated with improved mixture deformation resistance and increased mixture stiffness. However, the mixtures containing recycled plastic were also associated with an increase in moisture susceptibility and their fatigue lives were not significantly different to those of the control mixtures. Further research is recommended to better understand the modest reduction in moisture damage resistance associated with recycled plastic, as well as the digestion of recycled plastic via the dry-mixing process. 展开更多
关键词 ASPHALT plastic extender modifier.
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电脑操作超级助手——Filebox Extender
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作者 NaDa 《网友世界》 2004年第12期28-28,共1页
在电脑的各种操作中,我们用得比较频繁的是“另存为”和“打开”这两个操作。但Windows的设计不够人性化,使用这两个操作时,我们常常会展转于硬盘的各级目录。难道就不能让操作更为简洁吗?有了Filebox Extender就可以让你的操作一... 在电脑的各种操作中,我们用得比较频繁的是“另存为”和“打开”这两个操作。但Windows的设计不够人性化,使用这两个操作时,我们常常会展转于硬盘的各级目录。难道就不能让操作更为简洁吗?有了Filebox Extender就可以让你的操作一步到位! 展开更多
关键词 Filebox extender 操作系统 WINDOWS 电脑
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A Corpus-Based Study on General Extenders in Different Genres in American English
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作者 Wenjia Liu 《教育研究前沿(中英文版)》 2022年第2期129-135,共7页
This article investigates general extenders in American English,using a more than one-billion-word corpus(COCA)classified by different genres.In this study,the differences and frequencies of general extenders in diffe... This article investigates general extenders in American English,using a more than one-billion-word corpus(COCA)classified by different genres.In this study,the differences and frequencies of general extenders in different genres are displayed.The study also illustrates the tendency of the use of general extenders in American English from 1990 to 2020.Moreover,the salient features of general extenders used in different genres are observed.The study can provide some practical implications for the use of general extenders for second language learners. 展开更多
关键词 General extenders GENRES TENDENCY American English
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Chain Extender-induced Hydrogen Bonding Organization Determines the Morphology and Properties of Thermoplastic Polycarbonate Polyurethane
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作者 Yi-Lang Qin Ping Zhu +1 位作者 Chen-Xi Ouyang Xia Dong 《Chinese Journal of Polymer Science》 SCIE EI CAS CSCD 2024年第1期87-96,I0009,共11页
Thermoplastic polycarbonate polyurethanes(PCUs) are multiblock copolymers that have been applied for medical devices for long time. Aliphatic diols are common chain extenders(CE) involved in the composition of the har... Thermoplastic polycarbonate polyurethanes(PCUs) are multiblock copolymers that have been applied for medical devices for long time. Aliphatic diols are common chain extenders(CE) involved in the composition of the hard segments of PCU. However, limited knowledge was discovered about how the chemical structure of CE affects the hydrogen bonding organization within PCUs and their mechanical properties.To investigate this problem, a group of PCUs were synthesized respectively by extending the polymer chain with 1,4-butanediol(BDO),aminoethanol(MEA), ethanediol(EO) as three kinds of chain extenders. Tiny differences in the CE chemical structure results in remarkable variations in phase separation, condensed morphologies, thermal and mechanical properties, which are characterized by Fourier transform infrared spectrometer, atomic force microscopy, small-angle X-ray scattering, differential scanning calorimetry, and tensile tests. The microstructural evolution during unilateral deformation and the different mechanism induced by the different CEs was probed and unveil by in situ wide-and small-angle X-ray diffraction. Symmetry of CE can improve the organization of the hydrogen bonding. The coherence strength of the urethane/urea group also plays a key role by comparing the two PCUs with ethanediol and aminoethanol. 展开更多
关键词 Thermoplastic polycarbonate polyurethane Chain extender Hydrogen bonding Mechanical properties
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带Range-Extender纯电动汽车动力系统设计 被引量:6
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作者 尤寅 宋珂 尹东晓 《北京汽车》 2010年第3期41-43,46,共4页
引入Range-Extender概念,阐述纯电动汽车前期开发过程中动力系统参数的设计过程,旨在为纯电动汽车动力系统参数开发提供参考。
关键词 纯电动汽车 Range—extender 动力性能 动力系统参数
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The Extended Hybrid Carrier-Based Multiple Access Technology for High Mobility Scenarios 被引量:1
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作者 Ge Song Xiaojie Fang Xuejun Sha 《China Communications》 SCIE CSCD 2024年第1期53-68,共16页
The hybrid carrier(HC)system rooted in the carrier fusion concept is gradually garnering attention.In this paper,we study the extended hybrid carrier(EHC)multiple access scheme to ensure reliable wireless communicatio... The hybrid carrier(HC)system rooted in the carrier fusion concept is gradually garnering attention.In this paper,we study the extended hybrid carrier(EHC)multiple access scheme to ensure reliable wireless communication.By employing the EHC modulation,a power layered multiplexing framework is realized,which exhibits enhanced interference suppression capability owing to the more uniform energy distribution design.The implementation method and advantage mechanism are explicated respectively for the uplink and downlink,and the performance analysis under varying channel conditions is provided.In addition,considering the connectivity demand,we explore the non-orthogonal multiple access(NOMA)method of the EHC system and develop the EHC sparse code multiple access scheme.The proposed scheme melds the energy spread superiority of EHC with the access capacity of NOMA,facilitating superior support for massive connectivity in high mobility environments.Simulation results have verified the feasibility and advantages of the proposed scheme.Compared with existing HC multiple access schemes,the proposed scheme exhibits robust bit error rate performance and can better guarantee multiple access performance in complex scenarios of nextgeneration communications. 展开更多
关键词 extended hybrid carrier system high mo-Received:Jun.09 2023 Revised:Nov.20 2023 Editor:Yuanwei Liu bility communications multiple access
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