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71.
72.
本文提出了一种推算单电解质二元无机水溶液(火用)值的方法。其中,根据Pitzer普遍方程所得到的渗透系数公式和Gibbs—Duhem方程,推算出二元无机水溶液的化学值计算式,利用该计算式推导出NaCl、NH_4Cl和NaNo_3三种无机水溶液的化学与浓度的关系式,可方便地计算出不同浓度及溶液的化学,进而计算溶液 相似文献
73.
城市污泥热解过程中重金属的形态转化模拟研究 总被引:1,自引:0,他引:1
利用重金属Cd,Cu,Zn和Pb的碳酸盐、可溶性盐(如硫酸盐、硝酸盐、氯化盐)或硫化物作为污泥中重金属的模拟化合物,在不同条件下对模拟化合物进行热解.通过对热解产物进行X-射线衍射分析,确定产物的组成,从而推断污泥热解时重金属的形态变化过程.结果表明:Cd的碳酸盐热解过程中向更加稳定的CdS发生转变;Cu的碳酸盐和硫化物生成Cu2S;Zn的离子交换态和Pb的碳酸盐与离子交换态热解之后均生成相应的氧化物和硫化物. 相似文献
74.
研究了吉化污水处理厂两个车间排放的污泥中Cu、Zn、Cr、Pb、Cd的含量及形态分布.研究结果表明:采自中和处理车间污泥样品中重金属含量由高到低的顺序是Zn>Cu>Cr>Pb>Cd;采自污泥处理车间污泥样品中重金属含量由高到低的顺序是Cu>Zn>Cr>Pb>Cd.污泥样品中Cu的含量最高,为8487.58 mg/kg;Cd的含量最低,为2.72 mg/kg.BCR形态分析结果表明,2种污泥中Cu主要以可氧化态和残渣态存在;Zn主要以可氧化态和可还原态存在;Cr主要以残渣态存在;Pb的形态分布较为均匀;Cd主要以可还原态存在. 相似文献
75.
首次提出以BrФnsted酸性离子液体[BMIM]HSO4和H2SO4的复配体系作催化剂,用于汽油烷基化脱硫研究。研究结果表明,在相同反应条件下,相比硫酸,复配体系能够在最大限度不改变烯烃组成的情况下有效催化噻吩与烯烃进行烷基化反应;噻吩转化率随反应温度的增加而增加,但当温度超过45℃后,烯烃聚合速率增加幅度远大于噻吩转化幅度;噻吩转化率随反应时间的增加而增加,反应2h后反应基本达到平衡。 相似文献
76.
Lionel Feugre Gabriella Gibson Nicholas C. Manoukis Olivier Roux 《Journal of the Royal Society Interface》2021,18(177)
Given the unsurpassed sound sensitivity of mosquitoes among arthropods and the sound source power required for long-range hearing, we investigated the distance over which female mosquitoes detect species-specific cues in the sound of station-keeping mating swarms. A common misunderstanding, that mosquitoes cannot hear at long range because their hearing organs are ‘particle-velocity’ receptors, has clouded the fact that particle velocity is an intrinsic component of sound whatever the distance to the sound source. We exposed free-flying Anopheles coluzzii females to pre-recorded sounds of male An. coluzzii and An. gambiae s.s. swarms over a range of natural sound levels. Sound levels tested were related to equivalent distances between the female and the swarm for a given number of males, enabling us to infer distances over which females might hear large male swarms. We show that females do not respond to swarm sound up to 48 dB sound pressure level (SPL) and that louder SPLs are not ecologically relevant for a swarm. Considering that swarms are the only mosquito sound source that would be loud enough to be heard at long range, we conclude that inter-mosquito acoustic communication is restricted to close-range pair interactions. We also showed that the sensitivity to sound in free-flying males is much enhanced compared to that of tethered ones. 相似文献
77.
A novel synthesis methodology is reported for the preparation of NiS submicron particles in a green solvent 1-butyl-3methylimidazolium tetrafluoroborate (BMImBF4) ionic liquid (IL), using ultrasonic sonochemical technique. Structural, morphological and optical properties of nickel sulfide powders were obtained by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and diffuse reflectance spectroscopy (DRS). Composition was corroborated by energy dispersive X-ray spectroscopy (EDXS), both in the SEM and in the TEM. Regular shape particles were obtained under high-intensity ultrasonic irradiation for 105 min from the reaction between nickel nitrate and thioacetamide in ethanol/BMImBF4 (80:20), respectively. After vacuum annealing treatment at 180 °C overnight, spherical crystalline NiS particles were observed. The powders showed a band gap of 0.74 eV. 相似文献
78.
The extraction of Am3+ and Eu3+ by octyl(phenyl)-N,N-diisobutyl carbamoylmethylphosphine oxide (CMPO) in eight imidazolium-based ionic liquids and in n-dodecane was studied and compared. Slope analysis indicates that the ligand/metal ratio in the extracted complexes in ionic liquids is much larger than that in n-dodecane. Nitric acid has different impacts on the extraction, depending greatly on the nature of the ionic liquids. A mixed-extraction mechanism, namely cation exchange plus the formation of neutral complexes (solvation), was proposed for the extraction in the ionic liquid systems. In addition, temperature was found to have a remarkable influence on the extraction. Highly exothermic enthalpy changes were obtained for the extraction in ionic liquid systems. This work provides further insight into the particular role played by the unique properties of ionic liquids in the extraction of metal ions from nitric acid media. 相似文献
79.
Density functional theory has been performed to systematically study the interactions between RunPt13-n (n = 4, 7 and 9) clusters and [BMIM]+ based ionic liquids. Ionic liquids [BMIM][Br], [BMIM][BF4], [BMIM][PF6], [BMIM][CF3SO3], and [BMIM][NTf2] have different effects on the stability of Ru7Pt6. Ionic liquids with median size anions of PF6− and CF3SO3− can better improve the stability of Ru7Pt6 than those with the small anions of Br− and BF4− and large anion of NTf2−. Based on negative relaxation energies, the stabilities of Ru4Pt9, Ru7Pt6, and Ru9Pt4 are all enhanced after interacting with [BMIM][CF3SO3]. The stability enhanced degree is in agreement with the interaction strength. For Ru7Pt6–n{[BMIM][CF3SO3]} (n = 1, 2, 3, 4), the interaction between ionic liquid and cluster plays the primary role in stabilizing the cluster in Ru7Pt6–[BMIM][CF3SO3]. With the increase of the number of [BMIM][CF3SO3], the role of the interaction in stabilizing the cluster is getting weaker, while the role of steric protection is getting more important. 相似文献
80.
《Journal of the European Ceramic Society》2014,34(4):943-951
The oxygen ion conductivity of ultra dense, hot forged Bi4(MexV1−x)2O11 (BIMEVOX) ceramics is reported for the first time. A novel approach to electrode preparation, including laser trenching, was developed to perform 4-probe impedance spectroscopy and determine conductivity of small bar-shaped samples with high accuracy and precision. Hot forged (HF) Bi4(Cu0.05Ti0.05V0.90)2O11 (BICUTIVOX) ceramic, with modest preferred orientation (11%), exhibits anisotropy by a factor of 2 in its conductivity. Brick layer model (BLM) analysis of complex impedance plots reveals that the relative contribution of grains and grain boundaries to the total resistance is direction dependent, in the low temperature γ′ phase. The total ionic conductivity of BICUTIVOX, prepared either by hot-forging or conventional sintering, appears to be stable with thermal aging and cycling. Anisotropy in the thermal expansion of polycrystalline BIMEVOX ceramics is also reported. 相似文献