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1. chinaXiv:201711.00049 [pdf]

Effects of Rising Angle on Upstream Blades and Intermediate Turbine Duct

Liu, J., ; Wang, P.,; Du, Q., ; Liu, G. ; Zhu, J. Q.
Subjects: Physics >> General Physics: Statistical and Quantum Mechanics, Quantum Information, etc.

This paper describes the numerical study on film cooling effectiveness and aerodynamic loss due to coolant and main stream mixing for a turbine guide vane. The effects of blowing ratio, mainstream Mach number, surface curvature on the cooling effectiveness and mixing loss were studied and discussed. The numerical results show that the distributions of film cooling effectiveness on the suction surface and pressure surface at the same blowing ratio (BR) are different due to local surface curvature and pressure gradient. The aerodynamic loss features for film holes on the pressure surface are also different from film holes on the suction surface.

submitted time 2017-11-02 From cooperative journals:《热科学学报》 Hits828Downloads466 Comment 0

2. chinaXiv:201705.00215 [pdf]

Role of cis-1,4-cyclohexanedicarboxylic acid in the regulation of the structure and properties of a poly[butylene adipate-co-butylene 1,4-cyclohexanedicarboxylate] copolymer

Liu, F [Liu, Fei][ 1 ]; Qiu, J [Qiu, Jia][ 1 ]; Wang, JG [Wang, Jinggang][ 1 ]; Zhang, JW [Zhang, Junwu][ 1 ]; Na, HN [Na, Haining][ 1 ]; Zhu, J [Zhu, Jin][ 1 ]
Subjects: Materials Science >> Materials Science (General)

A unique non-planar ring structure 1,4-cyclohexanedicarboxylic acid (CHDA) is introduced to synthesize a poly(butylene adipate-co-butylene 1,4-cyclohexanedicarboxylate) (PBAC) copolyester. The impact of the stereochemistry of CHDA on the structure and properties of PBAC, especially the role of cis-CHDA in tuning the thermal, tensile and elastic properties of PBAC is explored in depth. Instead of considering PBAC as a diblock random copolymer consisting of poly(butylene adipate) (PBA) and poly(butylene 1,4- cyclohexanedicarboxylate) (PBC), our results reveal that PBAC can be considered as a random copolymer consisting of actually three blocks, namely PBA, a PBC unit with only trans-CHDA (trans- PBC), and PBC unit with only cis-CHDA (cis-PBC). The role of cis-CHDA is found to be rigid which initiates a high modulus and strength, and soft which results in a decreased melting temperature and increased elongation at break and elasticity.

submitted time 2017-05-09 Hits11287Downloads842 Comment 0

3. chinaXiv:201705.00095 [pdf]

Research progress on bio-based thermosetting resins

Ma, SQ [Ma, Songqi][ 1 ]; Li, TT [Li, Tingting][ 1,2 ]; Liu, XQ [Liu, Xiaoqing][ 1 ]; Zhu, J [Zhu, Jin][ 1 ]
Subjects: Physics >> General Physics: Statistical and Quantum Mechanics, Quantum Information, etc.

Compared with the rapid progress on bio-based thermoplastics, research on bio-based thermosetting resins should have attracted much more attention, considering that they will have a bright future. In this paper, the current research progress on bio-based thermosetting resins is reviewed. We pay special attention to the synthesis and investigation of properties of epoxies and unsaturated polyesters derived from renewable plant oil, cardanol, rosin acid, lignin, glycerol, gallic acid, furan, isosorbide, itaconic acid, etc. This mini review gives an overall perspective for bio-based thermosets. ? 2015 Society of Chemical Industry

submitted time 2017-05-08 Hits1226Downloads697 Comment 0

4. chinaXiv:201705.00601 [pdf]

Synthesis of poly[butylene terephthalate]-poly[tetramethylene glycol] copolymers using terephthalic acid as starting material: A comparation between two synthetic strategies

Zhang, JW [Zhang, Jun-wu][ 1 ]; Liu, F [Liu, Fei][ 1 ]; Wang, JG [Wang, Jing-gang][ 1 ]; Na, HN [Na, Hai-ning][ 1 ]; Zhu, J [Zhu, Jin][ 1 ]

Poly[butylene terephthalate]-poly[tetramethylene glycol] [PBT-PTMG] copolymer is prepared with terephthalic acid [PTA] rather than its dimethyl ester [DMT] as starting material by a two-step melt polycondensation. This process includes the synthesis of PB

submitted time 2017-05-02 Hits519Downloads300 Comment 0

5. chinaXiv:201705.00541 [pdf]

Synthesis of an intrinsically flame retardant bio-based benzoxazine resin

Yan, HQ [Yan, Hongqiang][ 1 ]; Sun, C [Sun, Chuang][ 1 ]; Fang, ZP [Fang, Zhengping][ 1 ]; Liu, XQ [Liu, Xiaoqing][ 2 ]; Zhu, J [Zhu, Jin][ 2 ]; Wang, H [Wang, Hao][ 3 ]
Subjects: Physics >> General Physics: Statistical and Quantum Mechanics, Quantum Information, etc.

An intrinsically flame retardant bio-based benzoxazine (diphenolic acid pentaerythritol caged phosphate benzoxazine, DPA-PEPA-Boz) monomer was synthesized from bio-based diphenolic acid (DPA) using a four-step process. The monomer of DPA-PEPA-Boz was characterized by FT-IR, 1H NMR and 13C NMR. The curing behavior of DPA-PEPA-boz was studied and compared with those of DPA based benzoxazine (DPA- Boz) and DPA ester derivative (MDP) based benzoxazine (MDP-Boz) without PEPA by means of non- isothermal differential scanning calorimetry. The results indicated that DPA-PEPA-Boz system showed a two-stage curing, assigned to the exothermic opening reactions of oxazine rings and PeOeC ring in PEPA respectively, while the DPA-Boz and MDP-Boz showed a one-stage curing. In addition, the effect of the introduction of PEPA on thermal and inflammable properties of the resin was evaluated. The residual char of the cured DPA-PEPA-Boz (P-DPA-PEPA-Boz) after 400 C was much higher than those of cured DPA-Boz (P-DPA-Boz) and cured MDP-Boz (P-MDP-Boz) under nitrogen and air atmospheres. Meanwhile, total heat release (THR), peak heat release rate (PHRR) and heat release capacity (HRC) of P-DPA-PEPA- Boz were about half of those of P-DPA-Boz and P-MDP-Boz. P-DPA-PEPA-Boz had a limiting oxygen index (LOI) of 33.5% and achieved V0 rating in UL94 test. P-DPA-PEPA-Boz behaved as a very good intrinsic thermal and flame retardant bio-based benoxazine resin.

submitted time 2017-05-02 Hits732Downloads432 Comment 0

6. chinaXiv:201705.00540 [pdf]

High bio-based content waterborne UV-curable coatings with excellent adhesion and flexibility

Dai, JY [Dai, Jinyue][ 1,2 ]; Ma, SQ [Ma, Songqi][ 1 ]; Wu, YG [Wu, Yonggang][ 2 ]; Zhu, J [Zhu, Jin][ 1 ]; Liu, XQ [Liu, Xiaoqing][ 1 ]
Subjects: Physics >> General Physics: Statistical and Quantum Mechanics, Quantum Information, etc.

A series of bio-based unsaturated polyesters was synthesized by melt polycondensation of itaconic acid with 1,4-butanediol and glycerol. Their chemical structures were confirmed by FT-IR, 1H NMR, acid and hydroxyl values. Waterborne UV curable dispersion coatings based on these polyesters and acrylated epoxidized soybean oil (AESO) were formulated. The average particle size and their stability before curing as well as the coating properties after curing, including adhesion, flexibility, pencil hardness and solvent resistance, were investigated. Results demonstrated that the glycerol segment in the polyesters together with AESO led to the excellent coating properties in terms of highest grade of adhesion (5B), 0T flexibility, pencil hardness of 5H and excellent solvent resistance (no appearance change after 250 double rubs with ethanol and acetone). This work provided us the coating systems combining the merits of being bio-based, UV-curable and water dispersible.vv

submitted time 2017-05-02 Hits661Downloads388 Comment 0

7. chinaXiv:201705.00529 [pdf]

Preparation of Biobased Monofunctional Compatibilizer from Cardanol To Fabricate Polylactide/Starch Blends with Superior Tensile Properties

Xiong, Z [Xiong, Zhu][ 1 ]; Dai, XY [Dai, Xinyan][ 1 ]; Zhang, RY [Zhang, Ruoyu][ 1 ]; Tang, ZB [Tang, Zhaobin][ 1 ]; Na, HN [Na, Haining][ 1 ]; Zhu, J [Zhu, Jin][ 1 ]
Subjects: Physics >> General Physics: Statistical and Quantum Mechanics, Quantum Information, etc.

A biobased monofunctional compatibilizer (called Epicard) is first synthesized by the reaction of cardanol with epichlorohydrin as confirmed by Fourier transform infrared and 1H NMR. Subsequently, biosourced polymers, polylactide (PLA) and starch, are melt-blended by a twin-screw extruder with Epicard. Confirmed by the measurements of contact angle and 1H nuclear magnetic resonance of the extracted starches from PLA/starch/Epicard blends, the Epicard only possesses a monoepoxy group to mainly react with starch and then increased the hydrophobicity of the starches during the melt-blending process. As a result, an obvious improvement to the interfacial adhesion between starch and PLA is observed by the scanning electron microscopy. Furthermore, the tensile properties of PLA/starch blends are effectively improved with the addition of Epicard. This study suggests a simple but effective material technique by utilizing a novel plant oil modifier to increase interfacial adhesion in fabricating fully biobased PLA/starch blends with superior tensile properties.

submitted time 2017-05-02 Hits568Downloads399 Comment 0

8. chinaXiv:201705.00499 [pdf]

Synthesis of polyurethane containing carbon-carbon double bonds to prepare functionalizable ultrafine fibers via electrospinning

Xue, WW [Xue, Wenwen][ 1 ]; Zhang, LS [Zhang, Lisheng][ 1 ]; Chen, HZ [Chen, Haizhen][ 1 ]; Wang, JG [Wang, Jinggang][ 1 ]; Na, HN [Na, Haining][ 1 ]; Zhu, J [Zhu, Jin][ 1 ]
Subjects: Physics >> General Physics: Statistical and Quantum Mechanics, Quantum Information, etc.

Polyurethanes (TPUs) containing carbon–carbon double bonds are synthesized for use as novel materials with the ability to form functionalizable ultrafine fibers via electrospinning. By adjusting the molecular structure, a series of TPU products with different amounts of carbon–carbon double bonds are obtained. After investigating the reactivity of the TPU with 1H,1H,2H,2H-perfluorooctanethiol, all of the TPU samples exhibit effective functionalizability. The more carbon–carbon double bonds contained in the molecular structure, the stronger the functionalizability. Besides, these TPUs can easily form uniform ultrafine fibers via electrospinning. Upon comparison, the functionalizability of the electrospun fibers is similar to that observed in the bulk TPU materials. This work suggests a feasible methodology to produce a functionalized ultrafine fibrous carrier. Accordingly, TPU containing carbon–carbon double bonds is expected to be exploited as a fibrous carrier of solid catalysts in the future.

submitted time 2017-05-02 Hits422Downloads284 Comment 0

9. chinaXiv:201705.00472 [pdf]

Diisocyanate free and melt polycondensation preparation of bio-based unsaturated poly[ester-urethane]s and their properties as UV curable coating materials

Han, LJ [Han, Lijing][ 1 ]; Dai, JY [Dai, Jinyue][ 1 ]; Zhang, LS [Zhang, Lisheng][ 1 ]; Ma, SQ [Ma, Songqi][ 1 ]; Deng, J [Deng, Jun][ 1 ]; Zhang, RY [Zhang, Ruoyu][ 1 ]; Zhu, J [Zhu, Jin][ 1 ]
Subjects: Physics >> General Physics: Statistical and Quantum Mechanics, Quantum Information, etc.

This paper reported the synthesis of bio-based unsaturated poly(ester- urethane)s via a nonisocyanate route, by metal-catalyzed melt poly- condensation of itaconic acid with urethanediols. Three novel types of bio-based unsaturated poly(ester-urethane)s, namely, poly- (urethanediol 2-itaconic acid), poly(urethanediol 4-itaconic acid) and poly(urethanediol 6-itaconic acid) (poly(U2-IA), poly(U4-IA) and poly (U6-IA) for short code, respectively), were prepared by a green synthetic route. The urethane linkage was formed by the reaction of two equivalent of ethylene carbonate with 1,6-hexanediamine, 1,4- butanediamine and 1,2-ethanediamine to form urethanediols. The urethanediols underwent polymerization with itaconic acid (IA) in the presence of metal catalyst dibutyltin dilaurate (DBTL) to produce low- molecular-weight bio-based unsaturated polyurethanes. Then, these bio-based unsaturated poly(ester-urethane)s were formulated with free radical photoinitiator and curing promoter to prepare UV curable polyurethane systems. After UV curing, the tensile properties, thermal properties and general coating properties of the three UV-cured polyurethane films were similar to that of UV cured polyurethane films prepared by polyurethane-acrylate (PUA). The results suggested that the obtained bio-based unsaturated polyurethanes could serve as coating materials.

submitted time 2017-05-02 Hits600Downloads330 Comment 0

10. chinaXiv:201705.00455 [pdf]

Folate-conjugated dually responsive micelles for targeted anticancer drug delivery

Zhao, LL [Zhao, Lingling][ 1,2 ]; Zhang, YJ [Zhang, Yajuan][ 1 ]; Shao, J [Shao, Jia][ 1 ]; Liang, HZ [Liang, Hongze][ 1 ]; Na, HN [Na, Haining][ 2 ]; Zhu, J [Zhu, Jin][ 2 ]
Subjects: Physics >> General Physics: Statistical and Quantum Mechanics, Quantum Information, etc.

Phenylboronic acid and folate grafted chitosan hydrochloride (FHCSPBA) was synthesized and confirmed by FTIR and 1H NMR. Glucose and pH dually responsive micelles were obtained through self-assembly of the amphiphilic polymers. The prepared FHCSPBA micelles displayed good biocompatibility and sustained drug release of the model drug doxorubicin hydrochloride (DOX). The cumulative drug release from the polymeric micelles showed obvious pH and glucose dependence and was accelerated by slightly decreasing the medium pH or increasing the glucose concentration. In vitro antitumor efficiency was evaluated by incubating the DOX loaded micelles with 4T1 breast cancer cells, and the results showed that folate-targeted micelles had higher antitumor activity than the non-targeted ones. Cellular uptake demonstrated by confocal microscopy indicated that free DOX was internalized in the nuclei of 4T1 cells, while the DOX loaded micelles were internalized in the cytoplasm. The cellular uptake of the micelles was enhanced by folate, with stronger fluorescence intensity in the cytoplasm, due to active FR-mediated endocytosis. These folate-conjugated glucose and pH dually responsive micelles may be a potential antitumor drug delivery system for cancer chemotherapy.

submitted time 2017-05-02 Hits417Downloads264 Comment 0

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