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Shale Gas Well Completions and Maximizing Gas Recoveries

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中国石油勘探 2009年第3期14卷 65-86页

作者： Michael d. Burnaman Stephen smith Wenwu Xia Harding Shelton Group Oklahoma City Oklahoma 73102

It is shown that stress fields within the earth are the principle control for hydraulic fracture direction in horizontal shale gas wells. Hydraulic fracturing is a process of increasing permeability within gas shales and involves a sophisticated organization of technology, good planning and proper management of equipment over a very short time period to be successful. The direction and extent of the induced fractures can be determined in near real-time at the well site via application of earthquake seismology theory in a now common process known as frac mapping. Next to the horizontal lateral azimuth, the total volume of slurry pumped into the well is a major factor in determining well EURs. Vertical fracture growth can be controlled and is important in concentration of the slurry within the main zone target zone that has the high TOC and porosity. Cemented casing with perforations is currently the most used method for zone isolation. New open-hole sleeve packers may eventually provide more flexibility in fracture design while also providing a means for refracturing multi-stage fractured horizontal wells, a technique not now commonly available. Multi-Stage fracture design requires incorporating rock properties with fracturing effect simulations and then verifying results using 3d reservoir simulations. Maximizing the gas recovery factors and EURs can be accomplished through use of closely spaced laterals with inter-fingered fracture stages and exploiting the stress shadow fracturing phenomenon. Even greater EURs may be possible if the wells can be refractured thereby opening up additional permeability channels. Shale gas development has progressed in an environmentally sensitive manner within the U.S. and will continue in this manner. during the past ten years, all of these technologies have been either newly developed or were the advancement of existing technology with modifications. The opportunity exists to take these proven technologies to other areas of the wor

关键词：石油天然气勘探开发

Hybrid graphene metasurfaces for highspeed mid-infrared light modulation and single-pixel imaging

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Light(Science & Applications) 2018年第1期7卷 524-531页

作者： Beibei Zeng Zhiqin Huang Akhilesh Singh Yu Yao Abul K.Azad Aditya d.Mohite Antoinette J.Taylor david R.smith Hou-Tong Chen Center for Integrated Nanotechnologies Los Alamos National LaboratoryLos AlamosNew Mexico 87545USA Center for Metamaterials and Integrated Plasmonics Department of Electrical and Computer EngineeringDuke UniversityDurhamNorth Carolina 27708USA MPA-11 Los Alamos National LaboratoryLos AlamosNew Mexico 87545USA School of Electrical Computer and Energy EngineeringArizona State UniversityTempeArizona 85287USA Chemistry Lifeand Earth Sciences DirectorateLos Alamos National LaboratoryLos AlamosNew Mexico 87545USA Present address:department of Chemical and Biomolecular Engineering Rice UniversityHoustonTexas 77005USA

during the past decades,major advances have been made in both the generation and detection of infrared light;however,its efficient wavefront manipulation and information processing still encounter great *** and fast optoelectronic modulators and spatial light modulators are required for mid-infrared imaging,sensing,security screening,communication and navigation,to name a ***,their development remains elusive,and prevailing methods reported so far have suffered from drawbacks that significantly limit their practical *** this study,by leveraging graphene and metasurfaces,we demonstrate a high-performance free-space mid-infrared modulator operating at gigahertz speeds,low gate voltage and room *** further pixelate the hybrid graphene metasurface to form a prototype spatial light modulator for high frame rate single-pixel imaging,suggesting orders of magnitude improvement over conventional liquid crystal or micromirror-based spatial light *** work opens up the possibility of exploring wavefront engineering for infrared technologies for which fast temporal and spatial modulations are indispensable.

关键词： modulator light prevailing

中国人头发纤维在UVA紫外光老化中的光谱学研究

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光谱学与光谱分析 2016年第6期36卷 1783-1788页

作者：唐颖 Gerald J.smith 北京工商大学北京市植物资源研究开发重点实验室北京100048 School of Chemical and Physical Sciences Victoria University of Wellington

生活中,日光中的紫外辐射是导致头发光老化/光损伤的重要环境因素。长时间光照可使染发和天然发出现包括颜色褪变在内的退行性变化。以中老年人的自然灰发为样本来源,通过分离和人工漂染处理,获得了包括自然发色、漂白和染黑的六种头发... 详细信息

生活中,日光中的紫外辐射是导致头发光老化/光损伤的重要环境因素。长时间光照可使染发和天然发出现包括颜色褪变在内的退行性变化。以中老年人的自然灰发为样本来源,通过分离和人工漂染处理,获得了包括自然发色、漂白和染黑的六种头发类型,经过UVA（320～400nm）紫外光老化,采用漫反射光谱、三维荧光光谱和衰减全反射傅里叶变换红外光谱对头发纤维的老化特征进行无损分析,结合头发中光产生过氧化氢的定量分析,探讨了不同发色和漂染处理对头发耐光性的影响。结果表明,UVA辐照可通过Ⅱ型电子转移机制诱导头发中的光敏基团产生过氧化氢,导致纤维表面蛋白和色素分子的光氧化降解。自然发色与漂染发在光老化中的颜色变化不同：灰发和白发主要发生光黄化,人工染发和漂白发分别发生光褪色和光漂白。高湿度环境能加速头发的光降解。化学漂染处理会使头发中的光致过氧化氢水平升高,使纤维处于较高的氧化压力从而影响头发的光稳定性;而头发中的黑色素分子,包括天然黑色素和染发剂的人工黑色素,可能具有自由基产生与清除双重性。研究结果为建立中国人头发光损伤的光谱学评价方法和进一步研发针对国人发质的染护发产品提供了重要的实验基准数据。

关键词：头发纤维 UVA辐射漫反射光谱三维荧光光谱 ATR-FTIR 过氧化氢

Conjugated Linoleic Acid and dietary Fats differentially Affect Hepatic ACAT Activity and LdL-Cholesterol in Postweanling Pigs Fed Low-Fat diets

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Journal of Animal Science and Biotechnology 2010年第2期1卷 75-84页

作者： S.B.smith T.A.Wilson C.d.Gilbert d.R.smith H.J.Mersmann department of Animal Science Texas A&M UniversityCollege StationTX 77843U.S.A Intercollegiate Faculty of Nutrition and department of Animal Science Texas A&M UniversityCollege StationTX 77843U.S.A. Independent Nutrition Consultant 2914 Colton PlaceCollege StationTX 77845U.S.A. USdA/ARS Children's Nutrition Research Center Baylor College of Medicine1100 Bates St.HoustonTX 77030(retired)U.S.A.

ABSTRACT：Two separate studies tested the hypoth- esis that plasma low-density lipoprotein cholesterol LdL-C ） can be decreased by conjugated linoleic acid （CLA） by depressing hepatic acyl-coenzyme A： cholesterol acyltransferase （ACAT） activity. In the first experiment, 3 groups of 6 early-weaned piglets were fed low-fat diets containing either 1.5% CLA, 1.5% corn oil or 1.5% beef tallow;fat provided 8% of the energy intake. In the second experiment, 4 groups of 6 early-weaned piglets were fed high-fat di- ets containing either 15% beef tallow, 12% beef tal- low plus 3% CLA, 15% corn oil, or 12% corn oil plus 3% CLA; fat provided 29% of energy intake. Cholesterol was balanced across diets in both experi-ments. In pigs fed the low-fat diets, all dietary fats in- creased LdL-C and triacylglycerols and decreased high-density lipoprotein cholesterol （ HdL-C ） and very low-density lipoprotein cholesterol （VLdL-C）. LdL-C was the same in pigs fed low-fat tallow or low-fat CLA diets. However, ACAT activity was near- ly 80% higher in pigs fed the low-fat tallow diet than in pigs fed the low-fat CLA diets. All high-fat diets increased LdL-C, HdL-C and triacylglycerols equally with no effect on VLdL-C. There were no unique fat- ty acid effects of the high-fat diets on ACAT activity. We conclude that supplemental fats had differential effects on hepatic ACAT activity and LdL-C, but on- ly in pigs fed low-fat diets.

关键词： acyl-coenzyme A: cholesterol acyltransferase conjugated linoleic acid fatty acids liver pigs

Fibroblast growth factor receptor 3 effects on proliferation and telomerase activity in sheep growth plate chondrocytes

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Journal of Animal Science and Biotechnology 2013年第1期4卷 41-48页

作者： Logan B smith Janelle M Belanger Anita M Oberbauer department of Animal Science University of California

Background： Fibroblast growth factor receptor 3 （FGFR3） inhibits growth-plate chondrocyte proliferation and limits bone elongation. Gain-of-function FGFR3 mutations cause dwarfism, reduced telomerase activity and shorter telomeres in growth plate chondroyctes suggesting that FGFR3 reduces proliferative capacity, inhibits telomerase, and enhances senescence. Thyroid hormone （1-3） plays a role in cellular maturation of growth plate chondrocytes and a known target of T3 is FGFR3. The present study addressed whether reduced FGFR3 expression enhanced telomerase activity, mRNA expression of telomerase reverse transcriptase （TERT） and RNA component of telomerase （TR）, and chondrocyte proliferation, and whether the stimulation of FGFR3 by T3 evoked the opposite response. Results： Sheep growth-plate proliferative zone chondrocytes were cultured and transfected with siRNA to reduce FGFR3 expression; FGFR3 siRNA reduced chondrocyte FGFR3 mRNA and protein resulting in greater proliferation and increased TERT mRNA expression and telomerase activity （p 〈 0.0.5）. Chondrocytes treated with T3 significantly enhanced FGFR3 mRNA and protein expression and reduced telomerase activity （p 〈 0.05）; TERT and TR were not significantly reduced. The action of T3 at the growth plate may be partially mediated through the FGFR3 pathway. Conclusions： The results suggest that FGFR3 inhibits chondrocyte proliferation and reducing telomerase activity indicating an important role for telomerase in capacity during bone elongation. by down-regulating TERT expression sustaining chondrocyte proliferative

关键词： Chondrocytes Growth-plate Telomerase Fibroblast growth factor receptor 3 Thyroid hormone Sheep

High-Level Accumulation of Exogenous Small RNAs Not Affecting Endogenous Small RNA Biogenesis and Function in Plants

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Journal of Integrative Agriculture 2014年第5期13卷 1017-1023页

作者： SHEN Wan-xia Neil A smith ZHOU Chang-yong WANG Ming-bo College of Plant Protection Southwest University CSIRO Plant Industry National Citrus Engineering Research Center Citrus Research Institute Chinese Academy of Agricultural Sciences

RNA silencing is a fundamental plant defence and gene control mechanism in plants that are directed by 20-24 nucleotide （nt） small interfering RNA （siRNA） and microRNA （miRNA）. Infection of plants with viral pathogens or transformation of plants with RNA interference （RNAi） constructs is usually associated with high levels of exogenous siRNAs, but it is unclear if these siRNAs interfere with endogenous small RNA pathways and hence affect plant development. Here we provide evidence that viral satellite RNA （satRNA） infection does not affect siRNA and miRNA biogenesis or plant growth despite the extremely high level of satRNA-derived siRNAs. We generated transgenic Nicotiana benthamiana plants that no longer develop the specific yellowing symptoms generally associated with infection by Cucumber mosaic virus （CMV） Y-satellite RNA （Y-Sat）. We then used these plants to show that CMV Y-Sat infection did not cause any visible phenotypic changes in comparison to uninfected plants, despite the presence of high-level Y-Sat siRNAs. Furthermore, we showed that the accumulation of hairpin RNA （hpRNA）-derived siRNAs or miRNAs, and the level of siRNA-directed transgene silencing, are not significantly affected by CMV Y-Sat infection. Taken together, our results suggest that the high levels of exogenous siRNAs associated with viral infection or RNAi-inducing transgenes do not saturate the endogenous RNA silencing machineries and have no significant impact on normal plant development.

关键词： Nicotiana benthamiana transformation satellite RNA RNA silencing small RNA

Ground-Based LidAR Improves Phenotypic Repeatability of Above-Ground Biomass and Crop Growth Rate in Wheat

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Plant Phenomics 2020年第1期2卷 138-148页

作者： david M.deery Greg J.Rebetzke Jose A.Jimenez-Berni Anthony G.Condon david J.smith Kathryn M.Bechaz William d.Bovill CSIRO Agriculture and Food CanberraACTAustralia CSIRO Agriculture and Food YancoNSWAustralia NSW department of Primary Industries YancoNSWAustralia

Highly repeatable,nondestructive,and high-throughput measures of above-ground biomass(AGB)and crop growth rate(CGR)are important for wheat improvement *** study evaluates the repeatability of destructive AGB and CGR measurements in comparison to two previously described methods for the estimation of AGB from LidAR:3d voxel index(3dVI)and 3d profile index(3dPI).Across three field experiments,contrasting in available water supply and comprising up to 98 wheat genotypes varying for canopy architecture,several concurrent measurements of LidAR and AGB were made from jointing to *** correlations at discrete events between AGB and the LidAR-derived biomass indices were significant,ranging from 0.31(Pding confidence in the LidAR indices as effective surrogates for *** repeatability of the LidAR biomass indices at discrete events was at least similar to and often higher than AGB,particularly under water *** correlations between calculated CGR for AGB and the LidAR indices were moderate to high and varied between ***,across all experiments,the repeatabilities of the CGR derived from the LidAR indices were appreciably greater than those for AGB,except for the 3dPI in the water-limited *** our experiments,the repeatability of either LidAR index was consistently higher than that of AGB,both at discrete time points and when CGR was *** findings provide promising support for the reliable use of ground-based LidAR,as a surrogate measure of AGB and CGR,for screening germplasm in research and wheat breeding.

关键词： Wheat Biomass LidAR

新型Ni-Cr-Co基高温合金在模拟煤燃烧环境中的高温腐蚀

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中国有色金属学报 2004年第3期14卷 340-345页

作者：赵双群谢锡善 G.d.smith 北京科技大学材料科学与工程学院 Special Metals Corporation

利用XRd,SEM和EdS等实验技术研究了一种新的超级超临界锅炉过热器管材Ni Cr Co基高温合金在模拟煤燃烧环境中的高温腐蚀行为。合金在700℃遭受的腐蚀过程分为2个阶段。在初始阶段,合金发生了氧化和硫化腐蚀,表面形成了保护性的Cr2O3膜,... 详细信息

利用XRd,SEM和EdS等实验技术研究了一种新的超级超临界锅炉过热器管材Ni Cr Co基高温合金在模拟煤燃烧环境中的高温腐蚀行为。合金在700℃遭受的腐蚀过程分为2个阶段。在初始阶段,合金发生了氧化和硫化腐蚀,表面形成了保护性的Cr2O3膜,同时出现了内硫化现象。在加速腐蚀阶段,因CoSO4熔盐在合金表面的稳定存在使合金遭受严重的低温热腐蚀。当处于较高的SO3分压时,钴或氧化钴在合金表面熔盐中的溶解是造成合金抗腐蚀性能退化的原因。

关键词： Ni-Cr-Co 高温合金高温腐蚀低温热腐蚀合成煤灰/烟气超级超临界锅炉过热器

Role of illness perception and self-efficacy in lifestyle modification among non-alcoholic fatty liver disease patients

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World Journal of Gastroenterology 2017年第10期23卷 1881-1890页

作者： Shira Zelber-Sagi Shiran Bord Gali dror-Lavi Matthew Lee smith Samuel d Towne Jr Assaf Buch Muriel Webb Hanny Yeshua Assy Nimer Oren Shibolet department of Gastroenterology TelAviv Medical Center School of Public Health University of Haifa Institute of Gerontology College of Public HealthThe University of Georgia Texas A&M University School of Public HealthCollege Station The Sackler Faculty of Medicine Tel-Aviv University Family Medicine department Tel-Aviv and Dan Petach-TikvaClalit Health ServicesRabin Medical Center Internal medicine A Galler medical Center Bar-Ilan University

To describe the relationships between non-alcoholic fatty-liver disease (NAFLd) patient’s disease consequences and treatment perceptions, self-efficacy, and healthy lifestyle *** cross-sectional study among 146 ultrasound diagnosed NAFLd patients who visited the fatty liver clinic at the Tel-Aviv Medical Center. Eighty-seven of these individuals, participated in a clinical trial of physical activity and underwent fasting blood tests, analyzed at the same lab. Exclusion criteria included positivity for serum HBsAg or anti-HCV antibodies; fatty liver suspected to be secondary to hepatotoxic drugs; excessive alcohol consumption (≥ 30 g/d in men or ≥ 20 g/d in women) and positive markers of genetic or immune-mediated liver diseases. Patients were asked to complete a self-report structured questionnaire, assembled by the Israeli Center for disease Control. Nutrition habits were measured using six yes/no questions (0 = no, 1 = yes) adopted from the national survey questionnaire. Participants in the clinical trial completed a detailed semi-quantitative food frequency questionnaire (FFQ) reporting their habitual nutritional intake during the past year. Self-efficacy was assessed by the Self-Efficacy Scale questionnaire, emotional representation, degree of illness understanding, timeline perception, treatment perception and symptoms were measured by the Brief Illness Perception questionnaire. Illness consequences were measured by the Personal Models of diabetes Interview questionnaire. A path analysis was performed to describe the interrelationships between the patients’ illness perceptions, and assess the extent to which the data fit a prediction of nutritional *** study sample included 54.1% men, with a mean age of 47.76 ± 11.68 years (range: 20-60) and mean body mass index of 31.56 ± 4.6. The average perceived nutrition habits score was 4.73 ± 1.45 on a scale between 0-6, where 6 represents the healthiest eating habits. Most of the study par

关键词： Non-alcoholic fatty-liver disease Physical activity diet Illness perception Self-efficacy