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苏宁 《应用数学学报(英文版)》1990,(2)
A degenerate parabolic system arising from the fluid-solute-heat flow through unsaturatedporous media is considered. The existence of weak solutions to the initial boundary value problemof this system is esteblished by parabolic regularizaton. The regularity is proved as well, i. e. theweak solutions satisfy the equations and initial boundary conditions pointwise in the region wherethe moisture content is positive. 相似文献
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In this paper we considered the first and the second boundary value problems for one-dimensionalfiltration in partially saturated porous media.The existence,uniqueness and regularity of weaksolutions were obtained.We also studied the interface problems and discussed the asymptotic behaviorof weak solutions. 相似文献
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Supercontinuum generation in seven-core photonic crystal fiber pumped by a broadband picosecond pulsed fiber amplifier 下载免费PDF全文
We report a supercontinuum source generated in seven-core photonic crystal fibers(PCFs) pumped by a self-made all-fiber picosecond pulsed broadband fiber amplifier. The amplifier's output average power is 60 W at 1150 nm with spectral width of 260 nm, and its repetition rate is 8.47 MHz with pulse width of 221 ps. With two different lengths of seven-core PCF, different output powers and spectra are obtained. When a 10 m long seven-core PCF is chosen, the output supercontinuum covers the wavelength range from 620 nm to 1700 nm, with the output power of 11.7 W. With only 2 m long seven-core PCF used in the same experiment, the wavelength of the supercontinuum spans from 680 nm to 1700 nm,with the output power of 20.4 W. The results show that the pulse width is 385 ps in the 10 m long seven-core PCF and 255 ps in the 2 m long one, respectively, due to the normal dispersion of the PCF. 相似文献
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提出了电感耦合等离子体原子发射光谱法测定烧结增效剂中主成分三氧化二硼和二氧化锰含量的方法。用盐酸-硝酸混合溶液溶解样品,选择波长257.610,249.773 nm两条谱线分别作为测定硼和锰的分析线,采用背景校正来扣除干扰。方法用于烧结增效剂样品分析,测定结果与化学法测定值相一致。 相似文献
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采用超声波混合、抽滤的方法把多壁碳纳米管(MWCNTs)和乙炔黑混合制备了锂离子电池用复合导电剂浆料,用扫描电子显微镜(SEM)和恒流充放电测试考察了复合导电剂的结构和其作为导电剂对LiCoO2电极放电比容量的影响.SEM的分析结果表明MWCNTs和乙炔黑实现了纳米层次的均匀混合.复合导电剂悬浮液和浆料分别被用作导电剂制成了两种LiCoO2电极,前一种电极为Cathode A,后一种电极为Cathode B,考察了不同MWCNTs含量时,两种电极0.5 C第10次放电比容量的差异.实验结果表明,随着MWCNTs含量的增加,两种电极放电比容量的差值增大,说明低含量MWCNTs的复合导电剂浆料是一种理想的锂离子电池导电剂. 相似文献
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MATHEMATICAL PROBLEMS ON THE FLUID-SOLUTE-HEAT FLOW THROUGH POROUS MEDIA Ⅱ. PARTIALLY SATURATED CASE
苏宁 《应用数学学报(英文版)》1990,(2)
A degenerate parabolic system arising from the fluid-solute-heat flow through partiallysaturated porous media is considered. The existence of weak solutions to the initial boundary valueproblem of this system is established by time discretization, and the continuity of the weak solutionsis discussed. 相似文献
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苏宁 《应用数学学报(英文版)》1990,(3)
In this paper an elliptic-parabolic coupled system arising from the fluid-solute-heat flowthrough a saturated porous medium is considerd.The uniqueness and the existence of classicalsolutions are proved.The asymptotic behavior of solutions for large time is shown,too. 相似文献
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In this paper, a new type of radio frequency (RF) excited diffusively cooled all-metal slab waveguide CO2 laser is presented, in which the waveguide channel is constructed by two aluminum side walls and two aluminum electrodes, the discharge is confined in the slab waveguide channel in terms of the voltage division structure. From this type of structure, 127-W laser power is obtained. 相似文献