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631.
采用水热法制备了不同Ag修饰量的Ag/MoO2纳米复合材料,并利用浸渍法将其负载在多孔泡沫镍(Nickel foam,NF)上制备成Ag/MoO2/NF无粘结剂型直接电极.在该电极中Ag/MoO2纳米颗粒均匀地负载在泡沫镍上形成了三维网络结构,其中MoO2纳米颗粒是由~10 nm的纳米晶组成.当Ag修饰量为5;时,Ag0.05/MoO2/NF具有最佳的电化学性能:在0.1 C的电流密度下,首次放电比容量高达1180 mAh/g,100次循环后仍保持805 mAh/g;且当电流密度由2 C降低至0.1 C时,比容量由468 mAh/g升高至820 mAh/g,表现出优异的储锂性能. 相似文献
632.
633.
在“星光Ⅱ”上进行几种特殊靶材盘靶和特殊结构腔靶产生超热电子和非线性过程 (受激Raman散射 (SRS)、双等离子体衰变 (TPD)、受激布里渊散射 (SBS)特征实验研究。该实验表明 :低ZCH泡沫或CH膜对抑制超热电子预热和非线性过程的产生是不利的 ,它们不作腔的第一打击面。 相似文献
634.
The elastic properties of syntactic foams with coated hollow spherical inclusions have been studied by means of Mori and Tanaka‘s concept of average stress in the matrix and Eshelby‘s equivalent inclusion theories. Some formulae to predict the effective modulus of this material have been derived theoretically. Based on these formulae, the influences of coating parameters such as the thickness and Poisson‘s ratio on the modulus of the syntactic foams have been discussed at the same time. 相似文献
635.
采用王水体系对地球化学样品进行水浴消解,聚氨酯泡塑吸附富集,硫脲解脱,电感耦合等离子体质谱(ICP-MS)法测定地球化学样品中的金元素。采用调谐液调节ICP-MS仪器至最佳化,以GAu-11b为标准,单点校正直接测定。对痕量金标准物质(GAu-12、GAu-13、GAu-11b、GAu-10a、GAu-2b、GAu-7b、GAu-8a)的分析结果与标准值相一致,方法相对标准偏差(RSD,n=12)为4.8%~6.7%。方法检出限为0.015ng/g,加标回收率为85.5%~100%。与常规石墨炉原子吸收光谱法测定方法相比较,ICP-MS法操作简单快捷、试剂用量少、信背比高,有利于大批量地球化学样品快速测定。 相似文献
636.
637.
Wieslaw Strek Przemysaw Wiewirski Wodzimierz Mita Robert Tomala Mariusz Stefanski 《Molecules (Basel, Switzerland)》2022,27(3)
A new method of hydrogen generation from water, by irradiation with CW infrared laser diode of graphene scaffold immersed in solution, is reported. Hydrogen production was extremely efficient upon admixing NaCl into water. The efficiency of hydrogen production increased exponentially with laser power. It was shown that hydrogen production was highly efficient when the intense white light emission induced by laser irradiation of graphene foam was occurring. The mechanism of laser-induced dissociation of water is discussed. It was found that hydrogen production was extremely high, at about 80%, and assisted by a small emission of O2, CO and CO2 gases. 相似文献
638.
A family of epoxy-based polymeric foams with various initial porosity levels was subjected to quasi-static uniaxial loading
in rigid confinement (uniaxial strain) to investigate their crushability characteristics. Two issues were investigated. The
first issue was the uniformity of deformation in a specimen as a function of porosity level by creating a grid of equally
spaced thin stripes on the surface and by monitoring their pattern during the experiment. It was found that the higher the
porosity of foam, the more non-uniform the deformation in the specimen. However, the localized non-uniform deformation did
not affect the global stress-strain response, especially at large deformations. The second issue was the development of a
new analysis tool, called “crushability map”. The purpose of the tool is to depict the evolution of porosity, bulk density
and energy absorption as functions of applied strain, stress, and porosity. These maps can assist in characterizing the residual
crushability or energy absorption capability of foams as a function of residual porosity. The maps can be used as a design
tool for selection of suitable foams for a given application in conjunction with various design criteria. 相似文献
639.
通过简单的原位生长法,将Cu3P纳米板阵列均匀负载在商业化的泡沫铜内部(NF?Cu3P@Cu),并用作锂金属负极的三维骨架载体材料。亲锂性的Cu3P纳米板阵列可以提供均匀且丰富的锂成核活性位点,诱导锂金属在NF?Cu3P@Cu内快速形核和均匀电沉积。同时,在电镀沉积锂时,Cu3P纳米板阵列会被锂化形成快离子导体Li3P,可以确保锂离子在复合负极中的快速均匀传输,从而有效抑制锂枝晶的形成。因此,获得的Li@NF?Cu3P@Cu复合负极材料在对称电池和全电池中,均表现出优异的循环稳定性。 相似文献
640.