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Synthesis and characterization of yellow water-borne polyurethane using a diol colorant as extender

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Chinese Chemical Letters 2010年第2期21卷 143-145页

作者： Zhang, He Zhang, Xing Yuan Dai, Jia Bing Li, Wei Hu Univ Sci & Technol China Dept Polymer Sci & Engn CAS Key Lab Soft Matter Chem Hefei 230026 Peoples R China

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...

关键词： Colored diol extender Polycaprolactonediol N N-bis（2-hydroxyethyl）-4-nitroaniline Yellow polyurethane

Preservability of rabbit semen after chilled storage in tris based extender enriched with different concentrations of Propolis ethanolic extract (PEE)

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Asian pacific Journal of Reproduction 2017年第2期6卷 68-76页

作者： Islam El-Sayed El-Seadawy Walid Said El-Nattat Magda Mohamed El-Tohamy Samy Ali Hussein Aziza Yakot Abdelfattah El-Senosy Ahmed Said Hussein Animal Reproduction and A I Dept.Veterinary Research DivisionNational Research CentreGizaEgypt Biochemistry and Clinical Biochemistry Dept. Faculty of Veterinary MedicineBenha UniversityEgypt Food Industry Dept Food Industry and Nutrition Research DivisionNational Research CenterGizaEgypt

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.

关键词： Male rabbits Semen extender Propolis extract Antioxidants HPLC

Effects of Bifunctional Chain extender on the Crystallinity and Thermal Stability of PET

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Journal of Materials Science and Chemical Engineering 2013年第6期1卷 9-15页

作者： Bo Liu Qianwei Xu Key Laboratory of Advanced Civil Engineering Materials of Ministry of Education Shanghai China School of Materials Science and Engineering Tongji University Shanghai China

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.

关键词： Poly(Ethylene Terephthalate) Chain extender Infrared Substractive Spectrum Intrinsic Viscosity

Characterization and Utilization of Eziulo Clay as an extender in Emulsion Paint Formulations

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Journal of Minerals and Materials Characterization and Engineering 2017年第4期5卷 174-184页

作者： Isaac O. Igwe Gift Osuoha Chinedu Nwapa Department of Polymer and Textile Engineering Federal University of Technology Owerri Nigeria

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 f

关键词： extender Emulsion Paint Eziulo Clay Drying Properties Titanium Dioxide Clay Particle Size Characterization

Laboratory Evaluation of Asphalt Containing Recycled Plastic as a Bitumen extender and Modifier

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Journal of Traffic and Transportation Engineering 2019年第5期7卷 218-235页

作者： Greg White Connor Magee School of Science and Engineering University of the Sunshine CoastSippy DownsQueenslandAustralia

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.

关键词： Asphalt plastic extender modifier.

Preliminary Study of Effects of Centrifugation of Stallion Semen on Motility and Pro-AKAP4 Concentration over 72 Hours Post-collection

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Journal of Agricultural Science and Technology(A) 2022年第2期12卷 65-72页

作者： Mikaila Zi Yue Smith Anna Dilger Erin Bryan Giana Bytnar Suhna Choi Kelly Cook Kevin Kline Department of Animal Sciences University of Illinois at Urbana Champaign1207 West Gregory DriveUrbanaIL 61801USA

The study aimed to investigate the effects of centrifugation of stallion semen on progressive sperm motility over a 72-hour period;and determine if the protein marker,precursor of A-kinase anchor protein 4(pro-AKAP4),may be maintained at a higher level over time when compared to non-centrifuged samples.Pro-AKAP4 has been studied for its function in stabilizing the structure of spermatozoa and its use as a marker for fertilizing capacity of spermatozoa.Semen collections were obtained from four fertile,commercially used Standardbred stallions collected three times each.Semen samples were diluted to a final concentration of 50 million total cells per milliliter.One extended aliquot of semen from each collection was used for the non-centrifuged treatment,and one extended aliquot of semen was centrifuged at 750×g for 10 min.The supernatant from the centrifuged sample was then removed with a 10 mL plastic transfer pipette,and the spermatozoa cell pellet was suspended in fresh extender to a final concentration of 50 million total cells per milliliter.Both centrifuged and non-centrifuged samples from each collection were stored in Equine Express II stallion semen shipping containers for 72 h and fresh ice packs were added to each container every 24 h.Both progressive sperm motility and levels of pro-AKAP4 were determined at times 0,12,24,48 and 72 h after collection.Differences were found between stallions,times and treatments with the main finding being that pro-AKAP4 concentration in centrifuged samples was maintained at a much higher level over the 72-hour period studied.

关键词： Centrifuged extender pro-AKAP4 spermatozoa stallion.

Study on Cryopreservative Effect of Three Penetrating Cryoprotectants with Three Kinds of extenders on Rabbit Spermatozoa

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Journal of Northeast Agricultural University(English Edition) 2001年第1期8卷 30-36页

作者： ZHANGGui－xue LIXiao－juan 等 NortheastAgriculturalUniversity HarbinHeilongjiangPRC150030

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.

关键词： rabbit spermatozoa cryopreservation extender cryoprotectant

Effect of Low-Sodium, Choline-Based Semen Diluent on Viability of Bovine Spermatozoa Stored at 4°C

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Advances in Reproductive Sciences 2018年第1期6卷 12-21页

作者： Pedro A. Delgado Toby D. Lester Rick W. Rorie Universidad Publica de El Alto El Alto Bolivia Department of Animal Sciences University of Arkansas Fayetteville AR USA

This study evaluated sperm viability over time, after dilution and refrigerator storage of fresh semen extended in either synthetic cauda epididymal plasma (CEP2), or in a low sodium medium (CJ2) supplemented with either AlbuMAX or egg yolk. Semen collected weekly for 4 weeks from 4 bulls and assigned within bulls, across treatments. After extension in either CEP2, or CJ2 containing either egg yolk or AlbuMAX, semen was cooled to 4°C, and evaluated for 7 days. A computer assisted sperm analysis (CASA) system was used for sperm evaluation. Particular emphasis was placed on sperm motility since it is the single most important sperm parameter influencing bull fertility. Total and progressive motility of sperm in CEP2 and CJ2-AlbuMAX were similar (P = 0.85 and P = 0.23, respectively), but both were lower (P extender supplemented with egg yolk is a viable alternative for storing fresh bovine semen.

关键词： Semen extender Bovine Sperm Refrigerator Storage

Comparing the Effects of Inputs for NTT and ArcAPEX Interfaces on Model Outputs and Simulation Performance

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Journal of Water Resource and Protection 2019年第5期11卷 554-580页

作者： Amanda M. Nelson Daniel N. Moriasi Mansour Talebizadeh Haile K. Tadesse Jean L. Steiner Prasanna H. Gowda Patrick J. Starks USDA-ARS-Grazinglands Research Laboratory El Reno OK US

The Agricultural Policy/Environmental extender (APEX) model has five different interfaces used to process and build simulation projects. These interfaces utilize different input databases that lead to different model default values. These values can result in different hydrologic, crop growth, and nutrient flow model outputs. This study compared structural and input value differences of the ArcAPEX and Nutrient Tracking Tool (NTT) interfaces. Long-term, water quality data from the Rock Creek watershed, located in Ohio were used to determine the impact of the differences on computation time, parameter sensitivity, and streamflow, total nitrogen (TN), and total phosphorus (TP) simulation performance. The input structures were the same for both interfaces for all files except soils, where NTT assigns three soil files per field, rather than a single one in ArcAPEX. As a result, computation times were three times as long for NTT as for ArcAPEX. There were twelve sensitive parameters in both cases, but the order of sensitivity was different. Both interfaces simulated streamflow well, but ARCAPEX simulated evapotranspiration, TN, and TP better than NTT, while NTT simulated crop yields better than ArcAPEX. However, none of the models met all of the performance criteria for either interface. Therefore, more work is needed to ensure models are properly calibrated before being used for scenario analysis. While it is acceptable for the values to be different from the SSURGO database, there is no documentation explaining the rationale for the modifications from the original source. This is one of the examples that highlights lack of detailed documentation that would be useful to model users. Overall, the results indicate that different interfaces lead to different model simulation results and, therefore, the authors recommend users specify the interface used and any modifications made to the associated databases when reporting model results.

关键词： Agricultural Policy Environmental extender (APEX) Calibration Sensitivity Analysis Parameterization Model Databases