Nanomaterials for Energy Application: Photocatalytic Hydrogen Production and Enhanced Oil Recovery

Prediction made by U.S. Energy Information Administration, energy demand will increase more than 40% in next 30 years and renewable energy is the fastest growing energy source at an average increase rate of 2.6%. Although lots of alternative energy sources have been developed, the majority are still from fossil fuels. After primary and secondary oil recovery, 30 - 60% of original oil in place (OOIP) is left in the oil field. Additional oil could be recovered by chemical injection, or an alternative method – nanofluid injection to reduce adverse ecological concerns. The primary objects of this research were aiming at applying nanotechnology for development/modification of existing nanomaterials for energy related applications: photocatalytic hydrogen production and enhanced oil recovery. One dimensional nanomaterials are considered favorably for electrons transport along axial direction due to the structural configuration. A green, novel, and fast microwave-assisted method was introduced to synthesize one dimensional CuO/TiO2 rods nanocomposites. Systematic investigation of deposited CuO amount on photocatalytic hydrogen production rate revealed that there was a CuO/TiO2 optimal ratio that enhanced hydrogen yield rate by 77 times. In addition, chemical vapor deposition was used to synthesize Zn3P2 nanowires and provided with in-situ surface functionalization. The surface modifier give Zn3P2 nanowires better resistance to moisture and degradation. Two dimensional nanodisks are able to attach at oil/water interface, known as Pickering emulsion, subsequently formed extremely stable emulsion droplets. ZrP nanodisks fabricated from three synthesis methods, hydrothermal, reflux, and microwave- assisted, are characterized and evaluated. In addition to fabrication methods, solvent also plays an important role in the synthesis procedure. Selected proper solvent provides a new route to obtain ZrP nanodisks less than 100 nm. Finally, the nanofluid containing amphiphilic ZrP nanodisks and microfluidic device for enhanced oil recovery was examined. The surface functional groups were served not only as surface modifier, but also capping agent to control the size of ZrP nanodisks in the one-pot synthesis procedure. The surface of ZrP nanodisks can be secondary functionalized to reach higher surface coverage of functional groups and further reduce interfacial tension of oil/water. The results showed oil recovery rate was increased in the presence of ZrP amphiphilic nanodisks

High expression FUT1 and B3GALT5 is an independent predictor of postoperative recurrence and survival in hepatocellular carcinoma.

Cancer may arise from dedifferentiation of mature cells or maturation-arrested stem cells. Previously we reported that definitive endoderm from which liver was derived, expressed Globo H, SSEA-3 and SSEA-4. In this study, we examined the expression of their biosynthetic enzymes, FUT1, FUT2, B3GALT5 and ST3GAL2, in 135 hepatocellular carcinoma (HCC) tissues by qRT-PCR. High expression of either FUT1 or B3GALT5 was significantly associated with advanced stages and poor outcome. Kaplan Meier survival analysis showed significantly shorter relapse-free survival (RFS) for those with high expression of either FUT1 or B3GALT5 (P = 0.024 and 0.001, respectively) and shorter overall survival (OS) for those with high expression of B3GALT5 (P = 0.017). Combination of FUT1 and B3GALT5 revealed that high expression of both genes had poorer RFS and OS than the others (P < 0.001). Moreover, multivariable Cox regression analysis identified the combination of B3GALT5 and FUT1 as an independent predictor for RFS (HR: 2.370, 95% CI: 1.505-3.731, P < 0.001) and OS (HR: 2.153, 95% CI: 1.188-3.902, P = 0.012) in HCC. In addition, the presence of Globo H, SSEA-3 and SSEA-4 in some HCC tissues and their absence in normal liver was established by immunohistochemistry staining and mass spectrometric analysis

The Study and Implementation of Network-Based Auditing System with Session Tracking and Monitoring

With consideration of the increasing importance of auditing system and the present auditing systems’ incapability of performing packet reassembling analysis, this research attempts to develop a “network-based auditing system with session tracking and monitoring” to assist network administrators to analyze and rearrange the packets into separate session groups. This developed system is able to reveal every single step of the unauthorized activities. As a result, the administrators can investigate each network session and its transferred data more efficiently, and reduced greatly the time for auditing data analysis. In addition, the event reconstruction simulates the actual event occurred at that time; this feature provides network administrators with more detailed and realistic insight concerning vulnerabilities in network security that need to be fixed. Also, this system keeps track of all network events, and collects related information in a set of auditing files (log files). Moreover, the collected records and reassembled files can serve as evidences in tracing cyber-crimes and as references for recovery process

EXPLORING E-LEARNING BEHAVIOR THROUGH LEARNING DISCOURSES

As many studies predict e-learning behaviors through intention, few of them investigate user’s learning behaviors directly. In addition to intention, individual’s e-learning behaviors may be influenced by technology readiness and group influences, such as social identity and social bond. This research-in-progress study explores how e-learning behaviors vary with intention, technology readiness, social identity and social bond. Our investigation was based on analyzing the speech acts embedded in fourteen learners’ online discourses in an eighteen-week e-learning course. We then compared how speech acts varied among groups with different degree of intention, technology readiness, social identity, and social bond. Our findings contribute e-learning research by clarifying how intention, technology readiness, social identity, and social bond influence learning behaviors in e-learning context

INFLUENCE OF APPROACH SPEED AND DISTANCE ON BIOMECHANICS DURING SINGLE-LEGGED RUNNING VERTICAL JUMP

The purpose of this study was to look into the kinematics, kinetics and EMG of the single legged running vertical jumps in different approach speed and distance. 12 basketball player performed single-legged running vertical jumps with 2 approach speed and 3 distance randomly. Kinematic and Kinetic data were collected by a force and 11 infrared high speed cameras. EMG data were recorded by Delsys surface EMG system. Two-way repeated measures AMOVA (2 speeds x 3 distance) was used for establishing differences (significance level p< .05). The jump height, jumt moment of lower extremity, knee power and the activation of tibialis anterior and gastrocnemius were found significantly larger in fast approach speed. We suggested using fast approach speed and 9m approach distance to enhance the single-legged running vertical jump ability

Light scattering properties beyond weak-field excitation in a few-atom system

In the study of optical properties of large atomic system, a weak laser driving is often assumed to simplify the system dynamics by linearly coupled equations. Here we investigate the light scattering properties of atomic ensembles beyond weak-field excitation through cumulant expansion method. By progressively incorporating higher-order correlations into the steady-state equations, an enhanced accuracy can be achieved in comparison to the exact solutions from solving a full density matrix. Our analysis reveals that, in the regime of weak dipole-dipole interaction (DDI), the first-order expansion yields satisfactory predictions for optical depth, while denser atomic configurations necessitate consideration of higher-order correlations. As the intensity of incident light increases, atom saturation effects become noticeable, giving rise to significant changes of light transparency, energy shift, and decay rate. This saturation phenomenon extends to subradiant atom arrays even under weak driving conditions, leading to substantial deviations from the linear model. Our findings demonstrate the potential of mean-field models as good extensions to linear models as it balances both accuracy and computational complexity, which can be an effective tool for probing optical properties in large atom systems. However, the crucial role of higher-order cumulants in large atom systems under finite laser field excitations remains unclear since it is challenging theoretically owing to the exponentially-increasing Hilbert space in such light-matter interacting systems.Comment: 4 figure