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931.
为了解决部分油井无法单管输送的问题,采用PIPESIM模拟软件对不同含水率、不同集输半径和不同产液量油井的集输管线进行计算分析,同时结合各油田单管集输设计经验,得出中质原油站外系统单管集油工艺改造的技术界限,而对于达不到技术界限的油井,可以通过辅助措施实现单管集油,通过对比电磁加热器、空气源热泵、管道内置电伴热、井口气电加热器、油井保温隔热油管、地热、太阳能光热技术及井口加药等单管辅助措施的原理及工艺特点,最终确定在不同工况条件下的辅助单管集输措施,为油田站外单管集输工艺选择和优化提供了理论依据。 相似文献
932.
Qin Du Wenli Wang Zhiguang Wang Wei Su Zhiyuan Deng Jingen Wu Ming Ma Zhongqiang Hu Ziyao Zhou Ming Liu 《Journal of the American Ceramic Society》2021,104(2):896-902
Perovskite materials with compositions in the vicinity of the steep morphotropic phase boundary (MPB) exhibit various intriguing properties including giant piezoelectricity and large dielectric constant. Aside from composition, the phase configuration of the perovskites is also strongly related to the ambient temperature. Here, we report a giant piezoelectricity of 10 980 pm/V at 93°C in the 0.7Pb(Mg1/3Nb2/3)O3-0.3PbTiO3 (PMN-PT) single crystals which is more than five times larger than that at room temperature. The enhanced piezoelectricity can be attributed to the instability of the thermally induced tetragonal phase which can be converted to the orthorhombic phase by the external electric field in the <011> oriented single crystal. The transverse piezoelectricity has been investigated by measuring the electric-field-dependent ferromagnetic resonance (FMR) field in the CoFeB/PMN-PT magnetoelectric (ME) heterostructures. The ME coupling coefficient has been increased from 49.3 to 476 Oe cm/kV as temperature increased from 25 to 90°C. The findings reveal that both longitudinal and transverse piezoelectricity in the PMN-PT single crystals can be greatly enhanced by proper setting of ambient temperature, indicating an effective route for the design of strain-mediated tunable devices with ultralow driving voltage. 相似文献
933.
Xiaoying Li Qiang Liu Xin Liu Danyang Zhu Dianjun Hu Feng Tian Lexiang Wu Zhaoxiang Yang Tengfei Xie Haohong Chen Jiang Li 《Journal of the American Ceramic Society》2021,104(5):2116-2124
Transparent terbium aluminum garnet (TAG) ceramics were achieved by the vacuum sintering plus HIP post-treating from the coprecipitated TAG nanoparticles. The influences of vacuum sintering temperature and sintering aid TEOS on the optical quality of the TAG ceramics were studied. The results show that with the increase of sintering temperature, the optical quality of TAG ceramics is improved gradually, and the in-line transmittance of the TAG ceramics treated at 1720°C for 20 hours under vacuum and then HIP post-treated at 1700°C for 3 hours under 200 MPa argon gas is 81.6% at 1064 nm. The sintering additive TEOS can improve the optical quality of TAG ceramics and inhibit the valence state change of Tb3+ ions to Tb4+ during the annealing process. The Verdet constant of the TAG ceramics at 632.8 nm is about −178 rad·T−1·m−1 at room temperature, which is 1.3 times that of the commercial TGG crystals (−134 rad·T−1·m−1). 相似文献
934.
Yongwang Li Yanqun Shao Weibin Zhang ShanShan Ye Jiangcong Zhou Mengting Chen Jianyan Ding Quansheng Wu Zhibiao Hu 《Journal of the American Ceramic Society》2021,104(12):6299-6308
Herein, a novel Bi3+-activated Ca3Y2Ge3O12 (CYGO) narrow-band cyan-emitting phosphor was synthesized. It can be excited from 320–420 nm, and the strongest excitation peak is located at 370 nm, which is suitable for current near-ultraviolet (NUV) chips perfectly. The full width at half maximum is at 52 nm. By analyzing the crystal structure of the sample, we infer that the Bi3+ ions replace the Y3+ site to form a highly symmetrical BiO6 octahedron. The time-resolved photoluminescence (TRPL) spectra of CYGO: Bi3+ reveal that the only a single emission center exists in the host lattice. A warm white light–emitting diode (WLED) device with a low correlated color temperature (3148 K) and a high color rendering index (90.2) was fabricated by using the as-prepared sample, and the significant thermal stability of CYGO: Bi3+ guarantees its potential application in WLEDs. It is verified that the structure with only one crystallographic Y site for Bi3+ dopant occupation and highly symmetrical and dense structure is conducive to realize narrow-band emission, which will provide experience for researchers to explore more Bi3+-activated phosphors used for high-end lighting. 相似文献
935.
Pang L. Zhang Z. W. Zhao Y. Huang S. Q. Hu Q. R. Zhao J. J. Yang K. Sun S. H. 《Combustion, Explosion, and Shock Waves》2021,57(5):597-606
Combustion, Explosion, and Shock Waves - Explosion venting experiments of corn starch are carried out in a small-scale container. With the help of a high-speed camera and a pressure sensor, an... 相似文献
936.
Hu Chuang Zang Guo-Long Luo Jun-Tao Liu Qi Zhao Quan 《Journal of Applied Electrochemistry》2021,51(6):847-859
Journal of Applied Electrochemistry - The electrocatalytic reduction of CO2 is a promising research direction in resource utilization and sustainable energy development. However, there is still a... 相似文献
937.
Guangyi Lin Shouyi Liu Siyuan Qu Guangkai Qu Tianya Li Zhenning Liang Yafei Hu Fumin Liu 《应用聚合物科学杂志》2021,138(18):50355
In this paper, a multi-layer gas diffusion layer (GDL) is designed. The GDL consists of a single carbon paper backing layer and dual microporous layers (MPLs). Moreover, the effects of thickness and hydrophobicity of double MPL on the performance of proton exchange membrane fuel cells are investigated. From the test results of the water contact angle, conductivity, pore size distribution, and the polarization curve, it is found that the thickness adjustment increases the number of 0.5 to 7 μm and 20 to 100 μm pores in GDL, which is more conducive to water discharge. Therefore, the thickness adjustment is more favorable to the cell performance under high humidity. While the gradient hydrophobic design makes the MPL of the modified intermediate layer have a certain water-retaining capacity to humidify the reaction gas, which has better effect under low humidity. At last, the results show that the optimized GDL meets a limit power density of 1.772 W/cm2 under 60% humidification and 1.600 W/cm2 under 100% humidification. 相似文献
938.
Fengshuo Hu John J. La Scala Santosh Kumar Yadav James Throckmorton Giuseppe R. Palmese 《应用聚合物科学杂志》2021,138(24):50579
A series of bio-rubber (BR) tougheners for thermosetting epoxy resins was prepared by grafting renewable fatty acids with different chain lengths onto epoxidized soybean oil at varying molar ratios. BR-toughened samples were prepared by blending BRs with diglycidyl ether of bisphenol A resins, Epon 828 and Epon 1001F, at different weight fractions and stoichiometrically cured using an amine curing agent, 4, 4′-methylene biscyclohexanamine (PACM). Fracture toughness properties of the unmodified and BR toughened polymer samples—including critical strain energy release rate (GIc), and critical stress intensity factor (KIc)—were measured to investigate the toughening effect of prepared BRs. It was found that the degree of phase separation and toughening were more controllable relative to similar polymers cured using the aromatic curing agent Epikure W, and the use of higher molecular epoxy resins produces a synergistic effect increasing the toughness much more than similar polymers made with lower molecular weight epoxy resins. Average BR domain sizes ranging from 200 to 900 nm were observed, and formulations with GIc, values KIc as high as 1.0 kJ/m2 and 1.4 MPa m1/2 were attained respectively for epoxy systems with Tg greater than 130°C. 相似文献
939.
Fengshuo Hu Santosh Kumar Yadav John J. La Scala James Throckmorton Giuseppe R. Palmese 《应用聚合物科学杂志》2021,138(24):50570
A series of bio-rubber (BR) reactive tougheners for thermosetting epoxy resins was prepared by grafting renewable saturated fatty acids of different chain lengths (C6-C14) onto epoxidized soybean oil (ESO) at varying molar ratios. The tunable nature of the BR systems derives from the architecture and functionality of naturally occurring molecules. Control of BR reactivity and molecular weight by varying the degree of grafting and the chain length of the fatty acid was demonstrated. The BR-toughened samples were prepared by blending BRs with diglycidyl ether of bisphenol A (DGEBA), Epon 828, and stoichiometrically curing the mixture using an aromatic amine hardener, diethyl toluene diamine (Epikure W). Fracture surface morphology studies showed that tuning of phase separated particle sizes was possible depending on the BR type and weight fraction. The resulting toughening effect was evaluated by measuring the fracture toughness of control and toughened polymer samples. The use of BRs significantly improved the critical strain energy release rate and critical stress intensity factor values of thermosetting polymer samples without significantly reducing Tg and modulus. In addition to toughening and adding renewable content to petroleum-based thermosetting epoxy systems these new tougheners have low viscosity compared to common alternatives and aid ease of processing. 相似文献
940.
Achieving synergetic improvements of mechanical strength, toughness, and thermal stability of epoxy resin has been a crucial but very challenging issue. Herein, to explore a new solution for circumventing this issue, polyimide microspheres were successfully prepared through the inverse nonaqueous emulsion process, and the structure, size distribution and morphologies of polyimide (PI) microspheres were comprehensively investigated. Then the PI microspheres were incorporated in epoxy resin matrix to systematically investigate the mechanical and thermal properties of obtained epoxy/PI microspheres composites. It was found that the PI microspheres can not only enhance the mechanical strength of epoxy resin, but also significantly improve the toughness. Specially, the epoxy-based composites containing 3 wt% PI microspheres exhibit a 47% increase in tensile strength, while the GIC and Charpy impact strength increase by 106% and 200%, respectively. The toughing mechanism of epoxy/PI microspheres composites was discussed. Moreover, the PI microspheres can also endow the epoxy resin with excellent thermal stability and heat resistance. Thus, this work may open a new opportunity to synergistically enhance the mechanical and thermal properties of epoxy-based composites and may also give some valuable inspiration for the rational design of other high-performance thermosetting composites. 相似文献