Hidden force opposing ice compression

Coulomb repulsion between the unevenly-bound bonding and nonbonding electron pairs in the O:H-O hydrogen-bond is shown to originate the anomalies of ice under compression. Consistency between experimental observations, density functional theory and molecular dynamics calculations confirmed that the resultant force of the compression, the repulsion, and the recovery of electron-pair dislocations differentiates ice from other materials in response to pressure. The compression shortens and strengthens the longer-and-softer intermolecular O:H lone-pair virtual-bond; the repulsion pushes the bonding electron pair away from the H+/p and hence lengthens and weakens the intramolecular H-O real-bond. The virtual-bond compression and the real-bond elongation symmetrize the O:H-O as observed at ~60 GPa and result in the abnormally low compressibility of ice. The virtual-bond stretching phonons (< 400 cm-1) are thus stiffened and the real-bond stretching phonons (> 3000 cm-1) softened upon compression. The cohesive energy of the real-bond dominates and its loss lowers the critical temperature for the VIII-VII phase transition. The polarization of the lone electron pairs and the entrapment of the bonding electron pairs by compression expand the band gap consequently. Findings should form striking impact to understanding the physical anomalies of H2O.Comment: arXiv admin note: text overlap with arXiv:1110.007

Analysis of properties to Distillers Dried Grains with Solubles (DDGS) and using destoner and low moisture anhydrous ammonia (LMAA) to utilize DDGS

With the rapid development of the ethanol industry, various research on distillers dried grains with solubles (DDGS) as a main co-product from the ethanol industry has been done in recent years. However, related research about basic properties to DDGS lacks of comprehensiveness. In addition, the efficient method and equipment to separate DDGS to high-valued fraction is still being investigated. Besides these, the possibility about using DDGS to produce ethanol is being explored, which is designed to own the advantages of comprehensiveness and systematicness. This thesis is prepared in paper format, and is comprised of three manuscripts, as follow: the first part was to examine 18 samples from 10 plants in Midwest area and utilize standard laboratory methods to measure a series of properties. Final results showed moisture content of 8.69% (w.b.), water activity of 0.55, angle of repose of 48.04 º, geometric mean diameter (dgw) of 0.74 mm, geometric standard deviation (Sgw) of 1.72 mm, loose bulk density of 483.9 kg/m3, packed bulk density of 568.5 kg/m3, Hunter L of 56.71, Hunter a of 13.85, Hunter b of 46.51, shear strength of 0.0324 kg/cm2. So it represents another step toward a complete baseline understanding of DDGS. The second part was to use a destoner fractionation process for separating distillers dried grains with solubles (DDGS) into streams with various compositions. Results showed that destoner fractionation was somewhat efficient and effective. Runs with 8° angle and 27.5 percent air flow resulted in the highest value of protein and oil, which the light fraction had 28.15% protein, 10.50% oil, while the heavy fraction had 31.30% protein and 17.20% oil. Particle size distribution had a positive correlation coefficient (0.93) with oil parameters and a negative correlation coefficient (-0.96) with moisture parameters. Fiber had no relationship with particle size, and protein had a weak correlation coefficient with (-0.54) to particle size. The third part described to use low-moisture anhydrous ammonia (LMAA) to pretreat DDGS and discussed varieties conditions to optimize the reaction. In previous research, low-moisture anhydrous ammonia (LMAA) pretreatment was investigated due to its high efficiency and less washing compared to other pretreatment methods. The final result showed that lower ammonia loading rate, higher moisture content, higher temperature and longer pretreatment time is evidently to improve the effect of ammonia to break lignocelluloses structure in DDGS, which can improve the hydrolysis of enzyme. Optimal LMAA conditions for DDGS were 80° C, 60% moisture content and 0.1 kg anhydrous NH3/kg dry biomass with a 168h pretreatment time. Also comparing with other methods, LMAA to DDGS has a higher efficiency and environmental conservation, which is potentially fit for industry produce. In the future study, the financial analysis to this method will be done to discuss the possibility of LMAA in industry produce

Techno-Economic Analysis (TEA) and Environmental Impact Assessment (EIA) of corn biorefinery and bioprocessing operation

With the rapid development of agricultural biorefinery and bioprocessing, economic efficiency and environmental effects have gradually been very popular studies in the advanced research of industrial process. As an important section of bioprocessing, the corn-based ethanol industry and oil refinery processes have been discussed fully, with details of technology, including material, reaction control, equipment and industrial applications. However, there are few studies of engineering economy and environmental effects on these processes and related products. In addition, most bioprocess research separately treats either economic efficiency or environmental effect, which lacks efficiency and comprehensiveness. Because of these obstacles, an efficient tool and software for engineering economics and environmental research is still being investigated. Due to the reasons above, this dissertation focused on techno-economic analysis (TEA) and environmental impact assessment (EIA) on the industrial corn-based ethanol process, advanced corn-soybean bio-refining and distillers dried grains with solubles (DDGS) separation process. This dissertation is prepared in a paper format, and is comprised of six chapters, as follows: The first chapter conducted initial techno-economic analysis (TEA) for a corn-based ethanol plant using data from 1982 to 2016. This study tested various procedures to assess the factors that affect ethanol plant profit, such as cost of corn, DDGS, ethanol, gas, electricity and so on. By using the updated U.S. Department of Agriculture (USDA) model, this study demonstrated the bioprocess modeling used to assess the economic performance of bioethanol plant systems, which provided a starting point for the analysis of advanced corn-soybean biorefinery. The second chapter expanded the scale of the first study model from 40 million gallons of ethanol per year to 120 million gallons of ethanol per year, and compared the effects to efficiency and profits during various scales. Similar to the first manuscript, this model was constructed using SuperPro Designer, and considered purchase and sale prices of materials and products, as well as estimated fixed costs, capital costs, revenues, and profits. This study provided a starting point for the analysis of advanced corn-soybean bio-refining in the future. The third chapter focused on advanced corn-soybean bio-refining using techno-economic analysis (TEA). By using the data of enzyme-assisted aqueous extraction processing (EAEP), this study demonstrated using the updated USDA model to simulate the corn-soybean bio-refining systems, and discuss the feasibility of industrial application for this technology. In addition, this chapter explored the difference in economic effects with original corn-based ethanol plants. The fourth chapter collected processing data from the previous three manuscripts, and utilized a method with a simple structure to easily assess environmental impacts. This method focused on the material or process steps that caused most of the potential environmental burden. Environmental impact assessment (EIA) concentrated more on the corn-based ethanol process itself, and was less time-consuming than complicated life cycle assessment (LCA). The fifth chapter determined techno-economics analysis of DDGS fractionation using a destoner to separate nutrients. Mathematical models were built for conducting techno-economic analysis (TEA), which allowed for estimations of capital costs, annual operating costs, annual revenues, and net profits. The techno-economics of the base case ethanol plant were examined by adjusting material and market costs, and estimating fractionation efficiencies and fraction prices based on protein content. This study demonstrated the possibility of using a destoner to fractionate DDGS to produce higher economic returns

Service Selection of Ensuring Transactional Reliability and QoS for Web Service Composition

Service-Oriented Architecture (SOA) provides a flexible framework of service composition. Using standard-based protocols, composite service can be constructed by integrating component services independently. As component services are developed by different organization and offer diverse transactional properties and QoS characteristics, it is a challenging problem how to select suitable component services which ensure reliable execution of composite Web service and construct the optimal composite Web service. In this paper, we propose a selection approach that combines transactional properties of ensuring reliability and QoS characteristics. In the selection approach, we build automaton model to implement transactional-aware service selection and use the model to guarantee reliable execution of composite Web service. We also define aggregation functions, and use a Multiple-Attribute Decision-Making approach for the utility function to achieve Qos-based optimal service selection. Finally, two scenarios of experiments are presented to demonstrate the validity of the selection approach

Sn(II)-containing phosphates as optoelectronic materials

We theoretically investigate Sn(II) phosphates as optoelectronic materials using first principles calculations. We focus on known prototype materials Sn$_n$P$_2$O$_{5+n}$ (n=2, 3, 4, 5) and a previously unreported compound, SnP$_2$O$_6$ (n=1), which we find using global optimization structure prediction. The electronic structure calculations indicate that these compounds all have large band gaps above 3.2 eV, meaning their transparency to visible light. Several of these compounds show relatively low hole effective masses ($\sim$2-3 m$_0$), comparable the electron masses. This suggests potential bipolar conductivity depending on doping. The dispersive valence band-edges underlying the low hole masses, originate from the anti-bonding hybridization between the Sn 5s orbitals and the phosphate groups. Analysis of structure-property relationships for the metastable structures generated during structure search shows considerable variation in combinations of band gap and carrier effective masses, implying chemical tunability of these properties. The unusual combinations of relatively high band gap, low carrier masses and high chemical stability suggests possible optoelectronic applications of these Sn(II) phosphates, including p-type transparent conductors. Related to this, calculations for doped material indicate low visible light absorption, combined with high plasma frequencies.Comment: 10 pages, 10 figures, Supplementary informatio