利用OLI ANALYZER STUDIO软件对安徽采油厂污水进行模拟分析

目前,油气田开发过程中的结垢现象已经成为我国各油田普遍存在的问题。充分了解开发过程中油田水的结垢趋势,进而做好防垢工作,对于保证老油田的高产稳产具有重要意义。采用OLI ANALYZER桌面水化学实验室模拟软件,对江苏油田安徽采油厂采出污水的沉淀-溶解平衡过程进行了热力学上的研究和分析。结果表明,该软件能够对难溶无机盐和地层矿物质在水中的沉淀-溶解平衡进行模拟,并能通过改变各种模拟条件来研究溶液体系中的化学反应,且操作方便。     

Fullerene-functionalized carbon nanotubes as improved optical limiting devices

We report the synthesis, characterization and optical limiting behavior of a nanohybrid built by grafting C₆₀-fullerenes on carbon nanotubes (CNTs). The nonlinear optical limiting properties of the CNT-C₆₀ complex were investigated at wavelengths where C₆₀ does not absorb. We found that the nanohybrid had superior performances to those of CNTs and fullerenes, either taken individually or as a mixture. This enhanced optical limitation of the nanohybrid suggests not only cooperative but also synergistic effects between the two carbon forms. A mechanism involving higher excitonic states of the CNTs formed by Auger recombination of low energy excitons is proposed.     

Gradient-Adaptive-Sigma (GAS) Grid for 3D Mass-Transport Modeling

The accuracy of three-dimensional (3D) mass transport modeling strongly relies on how well the vertical structures of the transport processes are resolved with the model resolution. The widely used vertical “stair-stepped” and topography following sigma (σ)-coordinate systems are fixed in time and space. Hence, these techniques often fail to resolve the details of the time varying, and highly nonlinear, activities in the water column. To better capture the geometrical details of these activities, a new vertical solution-adaptive grid method is introduced in this paper. The method takes into account the gradient variation of a selected variable in the mass transport field as an additional controlling factor in σ-coordinate transformation and so the new transformed grid is called a Gradient-Adaptive-Sigma (GAS) grid. The transformed grid spacing automatically adjusts in time and space according to the local solution gradient of the selected variable and converges in the high gradient regions for better resolution. The solution-adaptive method is implemented in a surface water numerical model to transform Cartesian coordinates into GAS coordinates. The model is established on the basis of an operator splitting scheme coupled with a Eulerian-Lagrangian method. Four numerical experiments describing the sediment transport activities of net entrainment and net deposition, and also pollutant dispersion, are performed with the transformed model. The computed results agree with the laboratory measurements. A comparison between the results computed by the GAS-gridded model and a σ-gridded model show that using the GAS-grid arrangement can improve the solution accuracy by as much as one-fold in regions of high solution gradients.     

Health and wellness monitoring through wearable and ambient sensors: exemplars from home-based care of elderly with mild dementia

Monitoring and timely intervention are extremely important in the continuous management of health and wellness among all segments of the population, but particularly among those with mild dementia. In relation to this, we prescribe three design principles for the construction of services and applications. These are ambient intelligence, service continuity, and micro-context. In this paper, we provide three exemplars from our research and development activities that illustrate the use of these design principles in the construction of services and applications. All the applications are drawn from the field of care for mild dementia patients in their living quarters.     

Influence of Undercooling and Nd4Ba2Cu2O10 Content on the Growth Rate of Large-Grain Bulk Nd-Ba-Cu-O Superconductor

The dependence of growth rate on isothermal undercooling and composition has been investigated for Nd-Ba-Cu-O single grains containing various amounts of nonsuperconducting Nd₄Ba₂Cu₂O₁₀ (Nd-422) phase inclusions and fabricated under a 1% O₂ in N₂ atmosphere using a top seeded melt growth technique. The growth rate along the crystallographic c -direction is observed to exceed that along the a / b direction at all undercooling temperatures and exhibits a maximum for a Nd-422 content of ∼10 mol%. The samples have been examined by optical microscopy and the results interpreted within an established planar solidification model.     

Rapid detection of oilfish and escolar in fish steaks: A tool to prevent keriorrhea episodes

The outbreak of keriorrhea caused by the wax ester-rich oilfish and escolar has become a frequent and worldwide concern. To help prevent such episodes, rapid detection of these fishes in the supply chain of the seafood industry and by food and health inspection agencies is essential. Through a combination of DNA, GC–MS and TLC analyses with reference to authentic samples, fish steaks of oilfish and escolar mislabeled as other species could be accurately identified. The TLC method developed is inexpensive and provides a reliable and importantly rapid identification within 30 min.     

High step-up converter with coupled-inductor

In this study, a high step-up converter with a coupled-inductor is investigated. In the proposed strategy, a coupled inductor with a lower-voltage-rated switch is used for raising the voltage gain (whether the switch is turned on or turned off). Moreover, a passive regenerative snubber is utilized for absorbing the energy of stray inductance so that the switch duty cycle can be operated under a wide range, and the related voltage gain is higher than other coupled-inductor-based converters. In addition, all devices in this scheme also have voltage-clamped properties and their voltage stresses are relatively smaller than the output voltage. Thus, it can select low-voltage low-conduction-loss devices, and there are no reverse-recovery currents within the diodes in this circuit. Furthermore, the closed-loop control methodology is utilized in the proposed scheme to overcome the voltage drift problem of the power source under the load variations. As a result, the proposed converter topology can promote the voltage gain of a conventional boost converter with a single inductor, and deal with the problem of the leakage inductor and demagnetization of transformer for a coupled-inductor-based converter. Some experimental results via examples of a proton exchange membrane fuel cell (PEMFC) power source and a traditional battery are given to demonstrate the effectiveness of the proposed power conversion strategy.     

Sensors and Machine Learning Models to Prevent Cooktop Ignition and Ignore Normal Cooking

Fire Technology - Cooking equipment is involved in nearly half of home fires in the United States, with cooktop fires the leading cause of deaths and injuries in cooking-related fires. In this...