A detailed chemical kinetic mechanism has been developed to describe the pyrolysis and oxidation of the hydrogen/NOx and syngas/NOx systems. The thermodynamic data of nitrogenous compounds have been updated based on t...
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This work examines the effects of spatial heterogeneity in regulating Cr(Ⅵ)sorption under different geostatistical characteristics and spatial scale *** flow-through experiments in heterogeneous columns of 0.1 meters...
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This work examines the effects of spatial heterogeneity in regulating Cr(Ⅵ)sorption under different geostatistical characteristics and spatial scale *** flow-through experiments in heterogeneous columns of 0.1 meters have shown that sorption in heterogeneous media can be characterized by three effective quantities: sorption capacity(Csc,m),early-stage fast sorption rate(kc1),and late-stage slow sorption rate(kc2).Two-dimensional reactive transport models are developed by calibrating these data from these columns of different illite distribution patterns and permeability contrasts between illite and quartz *** models were further run in geostatistical fields of different permeability variance(σ2lnκ,0.2 and 4.5)and length scale(0.1 to 1.0 m)conditions to quantify their role in determining effective sorption capacity and *** results indicate that in highly-connected columns with high permeability variance and long s,Cr(Ⅵ)-containing flow travels mostly through the high permeability,non-sorbing quartz *** therefore occurs mostly at the illite-quartz *** capacity and early fast rates(kc1)therefore depend strongly on the connectivity and properties that control advective transport of the *** longer time scales,diffusive transport determines the late-stage slow rates(kc2)and the breakthrough tailing,which depend less on connectivity and more on the size of the low-permeability illite zones and transverse dispersivity α*** to homogeneous columns of the same illite content,highly-connected patterns can reduce effective sorption capacity by up to a factor of 6.7,fast sorption rates by a factor of 25.0,and slow sorption rate by a factor of more than 2.0 orders of *** the domain length increases,the effects of spatial heterogeneities on sorption capacity and early stage fast sorption rates diminish due to longer length scales for mixing;these effects however persist for the late-stage slow sorp
Cryogen spray cooling has been applied to protect epidermis from thermal damage in laser dermatology. However, present clinical application suffers insufficient cooling capacity and non-uniform surface cooling. In pre...
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Molten salt reactor (MSR) as one candidate of the Generation IV advanced nuclear power systems is attracted more attention in China due to its top ranked fuel cycle and thorium utilization. The MSRs are characterized ...
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Laser-induced breakdown spectroscopy (LIBS) is an analytical detection technique based on atomic emission spectroscopy to measure the elemental composition. LIBS has been extensively studied and developed due to the n...
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Laser-induced breakdown spectroscopy (LIBS) is an analytical detection technique based on atomic emission spectroscopy to measure the elemental composition. LIBS has been extensively studied and developed due to the non-contact, fast response, high sensitivity, real-time and multi-elemental detection features. The development and applications of LIBS technique in Asia are summarized and discussed in this review paper. The researchers in Asia work on different aspects of the LIBS study in fundamentals, data processing and modeling, applications and instrumentations. According to the current research status, the challenges, opportunities and further development of LIBS technique in Asia are also evaluated to promote LIBS research and its applications.
Increasingly serious global warming caused by greenhouse gases has urged more and more focus on the sustainability. Exergy and carbon footprint are generally considered as two separate indicators to assess the greenho...
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Increasingly serious global warming caused by greenhouse gases has urged more and more focus on the sustainability. Exergy and carbon footprint are generally considered as two separate indicators to assess the greenhouse effect and sustainability of industrial production. In this paper we propose carbon exergy footprint (CEF) for quantitatively associating carbon footprint with exergy to evaluate the greenhouse effect of operating units. The indicator synthesizes the advantages of exergy and carbon footprint. Specific physical meaning for this novel indicator is illustrated on the basis of the second law of thermodynamics and life cycle assessment. The process of water-gas shift is chosen as the case for elaborating the behavior of CEF. Results show that CEF is competent for the objective evaluation for the greenhouse effect of the operating units. Additionally, CEF also maintains consistency with the conventional exergy analysis in terms of sustainability.
Surface frustrated Lewis pairs (SFLPs) have been implicated in the gas‐phase heterogeneous (photo)catalytic hydrogenation of CO 2 to CO and CH 3 OH by In 2 O 3− x (OH) y . A key step in the reaction pathway is envisi...
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Surface frustrated Lewis pairs (SFLPs) have been implicated in the gas‐phase heterogeneous (photo)catalytic hydrogenation of CO 2 to CO and CH 3 OH by In 2 O 3− x (OH) y . A key step in the reaction pathway is envisioned to be the heterolysis of H 2 on a proximal Lewis acid–Lewis base pair, the SFLP, the chemistry of which is described as In⋅⋅⋅In‐OH + H 2 → In‐OH 2 + ⋅⋅⋅In‐H − . The product of the heterolysis, thought to be a protonated hydroxide Lewis base In‐OH 2 + and a hydride coordinated Lewis acid In‐H − , can react with CO 2 to form either CO or CH 3 OH. While the experimental and theoretical evidence is compelling for heterolysis of H 2 on the SFLP, all conclusions derive from indirect proof, and direct observation remains lacking. Unexpectedly, we have discovered rhombohedral In 2 O 3− x (OH) y can enable dissociation of H 2 at room temperature, which allows its direct observation by several analytical techniques. The collected analytical results lean towards the heterolysis rather than the homolysis reaction pathway.
The application of spray towers for CO 2 capture is a development trend in recent years. However, most of the previous jobs were conducted in a cylindrical tower by using a single spray nozzle, whose configuration and...
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The application of spray towers for CO 2 capture is a development trend in recent years. However, most of the previous jobs were conducted in a cylindrical tower by using a single spray nozzle, whose configuration and performance is not good enough for industrial application. To solve this problem, the present work proposed a diameter-varying spray tower and a new spray mode of dual-nozzle opposed impinging spray to enhance the absorption performance of CO 2 spray absorption process. Experiments were conducted to investigate the effects of varies operating parameters on the overall mass transfer coefficient in various operating conditions. Experimental results showed that liquid to gas ratio and mole ratio of MEA to CO 2 are key factors which affect the performance of CO 2 absorption process and the maximum overall mass transfer coefficient for the diameter-varying dual-nozzle opposed impinging spray tower is 0.4773 kmol·m -3 ·h -1 ·kPa -1 .
In turbulent flow drag reduction applications, surfactant additive is more applicable than polymer for the flow with high shear or in the closed circulation system due to its reversible mechanical degradation advantag...
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