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Anomalously Strong Scattering of Spontaneously Produced Laser Radiation in the First Free-Electron Laser and Study of Free-Electron Two-Quantum Stark Lasing in an Electric Wiggler with Quantum-Wiggler Electrodynamics

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Chinese Physics Letters 2006年第6期23卷 1422-1425页

作者： S. H. Kim Department of Physics University of Texas at Arlington PO Box 19059 Arlington Texas 76019 USA

We calculate the scattering cross section of an electron with respect to the spontaneously produced laser radiation in the first free-electron laser （FEL） with quantum-wiggler electrodynamics （QWD）. The cross section is 1016 times the Thomson cross section, confirming the result obtained by a previous analysis of the experimental data. A QWD calculation show that spontaneous emission in an FEL using only an electric wiggler can be very strong while amplification through net stimulated emission is practically negligible.

关键词： CLASSICAL ELECTRODYNAMICS RELATIVISTIC ELECTRONS THERMODYNAMICS EXPLANATION EMISSION

A flexible metal-organic framework with double interpenetration for highly selective CO2 capture at room temperature

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Science China Chemistry 2016年第8期59卷 965-969页

作者： Bin Li Banglin Chen Department of Chemistry University of Texas at San Antonio San Antonio Texas 78249-0698 USA

A flexible metal-organic framework of la Cu（FMA）（4,4＇-Bpe）0.s （FMA=fumarate; 4,4＇Bpe=trans-bis-（4-pyridyl）ethylene） that exhibits guest molecule-controlled gate-opening adsorption has been reported, in which the flexible pores can be enlarged by CO2 molecules rather than CH4 and N2 under a certain gate-opening pressure. The CO2 uptake can be sharply improved from 6.85 cm3 gq at 0.60 atm to 33.7 cm3 g^-1 at 1 atm due to the gate-opening effect, thus resulting in the notably enhanced adsorption selectivities for CO2/CH4 （32：1, v/v） and CO2/N2 （48：1, v/v） separations at room temperature.

关键词： metal-organic framework flexible C02 capture selectivity gate-opening effect

A review of methane leakage from abandoned oil and gas wells:A case study in Lubbock,texas,within the Permian Basin

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Energy Geoscience 2024年第3期5卷 1-12页

作者： Stanley U.Opara Chinedu J.Okere Bob L.Herd Department of Petroleum Engineering Texas Tech UniversityTXUSA

In the pursuit of global net zero carbon emissions and climate change mitigation,ongoing research into sustainable energy sources and emission control is *** review examines methane leakage from abandoned oil and gas(AOG)wells,focusing particularly on Lubbock,a geographic area situated within the larger region known as the Permian Basin in West texas,United *** objective is to assess the extent and environmental implications of methane leakage from these *** analysis integrates pertinent literature,governmental and industry data,and prior Lubbock *** affecting methane leakage,including well integrity,geological characteristics,and human activities,are *** research estimates 1781 drilled wells in Lubbock,forming a foundation for targeted assessments and monitoring due to historical drilling *** hierarchy of well statuses in Lubbock highlights the prevalence of“active oil wells,”trailed by“plugged and abandoned oil wells”and“inactive oil wells.”Methane leakage potential aligns with these well types,underscoring the importance of strategic monitoring and *** analysis notes a zenith in“drilled and completed”wells during *** our study's case analysis and literature review reiterate the critical significance of assessing and mitigating methane emissions from AOG wells,it's important to clarify that the research does not directly provide methane leakage ***,it contextualizes the issue's magnitude and emphasizes the well type and status analysis's role in targeted mitigation *** summary,our research deepens our understanding of methane leakage,aiding informed decision-making and policy formulation for environmental *** clarifying well type implications and historical drilling patterns,we aim to contribute to effective strategies in mitigating methane emissions from AOG wells.

关键词： Net zero carbon emissions Climate change mitigation Methane emission control Abandoned oil and gas(AOG)well Permian Basin

Moisture-driven phase transition for improved perovskite solar cells with reduced trap-state density

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Nano Research 2017年第4期10卷 1413-1422页

作者： Swaminathan Venkatesan Fang Hao Junyoung Kim Yaoguang Rong Zhuan Zhu Yanliang Liang Jiming Bao Yan Yao Department of Electrical and Computer Engineering and Materials Science and Engineering Program University of Houston Houston Texas 77204 USA texas Center for Superconductivity at the University of Houston Houston Texas 77204 USA

We report a mechanistic understanding of a moisture-driven intermediate-phase transition that improves the quality of perovskite thin films based on a lead-acetate precursor, improving the power-conversion effidency. We clarify the composition of the intermediate phase and attribute the transition of this phase to the hygroscopic nature of the organic product, i.e., methylammonium acetate. Thermal annealing aids in the coarsening of the grains. These decoupled processes result in better crystal formation with a lower spatial and energetic distribution of traps. Thermal annealing of the films without exposure to air results in a faster intermediate-phase transition and grain coarsening, which occur simultaneously, leading to disorder in the films and a higher deep trap-state density. Our results indicate the need for a humid environment for the growth of high-quality perovskite films and provide insight into intermediate-phase dissociation and conversion kinetics. Thus, they are useful for the large-scale production of effident solution-processed perovskite solar cells.

关键词： perovskite solar cells phase transition moisture treatment film growth

Nondegloving technique for Peyronie＇s disease with penile prosthesis implantation and double dorsal-ventral patch graft

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Asian Journal of Andrology 2018年第1期20卷 90-92页

作者： Andrew Fang Run Wang Division of Urology University of Texas McGovern Medical School Houston Texas 77030 USA Department of Urology University of Texas MD Anderson Cancer Center Houston Texas 77030 USA

Acircumcising incision to deglove the penis for penile prosthesis （PP） implantation can increase the risk of ischemic injury to the glans penis. In order to avoid vascular complications, we describe a novel technique utilizing a ventral incision to perform the PP implantation and a double-dorsal patch graft, or ＂sliding technique＂（ST）, in patients with severe Peyronie＇s disease （PD）.＇Ihree patients with severe PD and erectile dysfunction at our institution underwent ST and PP implantation through a ventral incision. ＂[his new approach was not only successful in facilitating the ST and PP implantation in these patients but also allowed for adequate exposure of the penile shaft with no reported loss of sensation.

关键词： vascular complications erectile dysfunction

Comparison and integration of CuInGaSe and perovskite solar cells

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Journal of Energy Chemistry 2023年第3期78卷 463-475,I0013页

作者： Weiguang Chi Sanjay K.Banerjee Microelectronics Research Center Department of Electrical and Computer EngineeringThe University of Texas at AustinAustinTexas 78758USA

The rapidly developing perovskite solar cells(PSCs) provide a new and promising choice of thin film solar cells due to their attractive *** the commercialized thin film solar cells,CuInGaSe(CIGS)cells demonstrate higher efficiency than amorphous Si photovoltaic devices and lower toxicity than CdTe ***,a wide variety of studies have been conducted on ***,we elucidate CIGS materials and perovskites as absorber in thin film solar cells in terms of structure and optoelectronic ***,a comparison of PSCs and commercialized CIGS cells is made from the point of view of fabrication process,stability,and *** addition,the integration of CIGS devices and PSCs is elaborated based on tandem ***,prospects for the advancement of CIGS cells and PSCs are discussed.

关键词： CuInGaSe solar cells Perovskite solar cells Process Stability Toxicity Tandem

Sudden enhancement of sedimentation flux of^(210)Pb_(ex) as anindicator of lake productivity as exemplified by Lake Chenghai

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Science China Earth Sciences 2005年第4期48卷 484-495页

作者： P. H. Santschi Department of Marine Sciences Texas A&M University Galveston Texas 77551 USA

The fundamental assumption of 210Pbsediment dating is the stable flux of 210Pbse, which was derived from atmosphere and then transferred into sediments via lake water. When the sedimentation rate is relatively constant, the 210Pbse activity in sediments will be exponentially reduced with sedimentation age. 210Pbse in lake water is incorporated into sediments mainly via organic particulates. If the sedimentation flux of organic matter in lake water is suddenly in- creased, 210Pbse will be significantly deposited and then transferred into sediments. On the one hand such sudden purification effect is obviously unfit for the fundamental assumption of 210Pbse dating; on the other hand, the sudden enhancement of 210Pbse flux would be indicative of the conspicuous variation of primary productivity of lake water. This problem will be discussed in accordance with the variation trend of 210Pbex in the vertical profile of recent sediments of Lake Chenghai, Yunnan Province. The sediment core was collected from the deep-water area of Lake Chenghai in June 1997. The vertical profile of 137 Cs activity is characterized by a tree-peak pat- tern. This profile gave reliable ages, and also showed the stability of sediment accumulation in the recent ten years. The vertical profile of210Pbse activity displays a specific distribution of peaks, and is similar to the vertical profile of Corg. This phenomenon seems to be related to the mecha- nism of constraining the transfer of 210Pbse into lake sediments. The average atomic ratios of Horg/Corg and Corg/Norg in Lake Chenghai sediments are 5.51 and 7.04, respectively, indicating that the organic matter was predominantly derived from the remains of endogenic algae. In terms of the three-stage evolutionary characteristics of organic matter in sediments, i.e., “deposition-de- composition-accumulation”, the sedimentation fluxes （F（Corg）） of organic carbon （Corg） since 1970 were calculated by modeling. The sedimentation fluxes of 210Pbse (F(210P

关键词： sudden purification effect, 210Pbex, primary productivity of lake, Lake Chenghai.

Automatic Lane-Level Intersection Map Generation using Low-Channel Roadside LiDAR

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IEEE/CAA Journal of Automatica Sinica 2023年第5期10卷 1209-1222页

作者： Hui Liu Ciyun Lin Bowen Gong Dayong Wu the Department of Traffic Information and Control Engineering Jilin UniversityChangchun 130022 the texas A&M Transportation Institute Texas A&M UniversityCollege StationTexasTX 77843 USA

A lane-level intersection map is a cornerstone in high-definition(HD) traffic network maps for autonomous driving and high-precision intelligent transportation systems applications such as traffic management and control, and traffic accident evaluation and prevention. Mapping an HD intersection is time-consuming, labor-intensive, and expensive with conventional methods. In this paper, we used a low-channel roadside light detection and range sensor(LiDAR) to automatically and dynamically generate a lane-level intersection, including the signal phases, geometry, layout, and lane directions. First, a mathematical model was proposed to describe the topology and detail of a lane-level intersection. Second, continuous and discontinuous traffic object trajectories were extracted to identify the signal phases and times. Third, the layout, geometry, and lane direction were identified using the convex hull detection algorithm for trajectories. Fourth, a sliding window algorithm was presented to detect the lane marking and extract the lane, and the virtual lane connecting the inbound and outbound of the intersection were generated using the vehicle trajectories within the intersection and considering the traffic rules. In the field experiment, the mean absolute estimation error is 2 s for signal phase and time identification. The lane marking identification Precision and Recall are96% and 94.12%, respectively. Compared with the satellite-based,MMS-based, and crowdsourcing-based lane mapping methods,the average lane location deviation is 0.2 m and the update period is less than one hour by the proposed method with low-channel roadside LiDAR.

关键词： High-definition map lane-level intersection map roadside LiDAR sliding window traffic object trajectory

Multisensor Data Fusion for High Quality Data Analysis and Processing in Measurement and Instrumentation

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Journal of Bionic Engineering 2007年第1期4卷 53-62页

作者： Yan-bo Huang Yu-bin Lan W. C. Hoffmann R. E. Lacey USDA ARS Agricultural Engineer Areawide Pest Management Research Unit Texas 77845 USA Biological and A g ricultural Engineering Department Texas A ＆M University Texas 77843-2117 USA

Multisensor data fusion （MDF） is an emerging technology to fuse data from multiple sensors in order to make a more accurate estimation of the environment through measurement and detection. Applications of MDF cross a wide spectrum in military and civilian areas. With the rapid evolution of computers and the proliferation of micro-mechanical/electrical systems sensors, the utilization of MDF is being popularized in research and applications. This paper focuses on application of MDF for high quality data analysis and processing in measurement and instrumentation. A practical, general data fusion scheme was established on the basis of feature extraction and merge of data from multiple sensors. This scheme integrates artificial neural networks for high performance pattern recognition. A number of successful applications in areas of NDI （Non-Destructive Inspection） corrosion detection, food quality and safety characterization, and precision agriculture are described and discussed in order to motivate new applications in these or other areas. This paper gives an overall picture of using the MDF method to increase the accuracy of data analysis and processing in measurement and instrumentation in different areas of applications.

关键词： multisensor data fusion artificial neural networks NDI food quality and safety characterization precision agriculture