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国外锡工业 1994年第2期22卷 41-52页

作者： sears,b 袁世泽

Design concerns of room and pillar retreat panels

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International Journal of Mining Science and Technology 2017年第1期27卷 29-35页

作者： Klemetti Ted M. sears Morgan M. Tulu Ihsan b. Mining Engineer Ground Control branch NIOSH Office of Mine Safety and Health ResearchPittsburghPAUSA

Why do some room and pillar retreat panels encounter abnormal conditions？ What factors deserve the most consideration during the planning and execution phases of mining and what can be done to mitigate those abnormal conditions when they are encountered7 To help answer these questions, and to determine some of the relevant factors influencing the conditions of room and pillar （R ＆ P） retreat min- ing entries, four consecutive R ＆ P retreat panels were evaluated. This evaluation was intended to rein- force the influence of topographic changes, depth of cover, multiple-seam interactions, geological conditions, and mining geometry. This paper details observations were made in four consecutive R ＆ P retreat panels and the data were collected from an instrumentation site during retreat mining. The pri- mary focus was on the differences observed among the four panels and within the panels themselves. The instrumentation study was initially planned to evaluate the interactions between primary and secondary support, but produced rather interesting results relating to the loading encountered under the current mining conditions. In addition to the obse^ation and ｜ll^trumentation, numerical modeling was per- formed to evaluate the stress condi~!ons. both the LaModel 3.0 and Rocscience Phase 2 programs were used to evaluate these four panels, The results of both models indicated a drastic reduction in the vertical stresses experienced in these panels due to the full extraction mining in overlying seams when compared to the full overburden load. both models showed a higher level of stress associated with the outside entries of the panels. These results agree quite well with the observations and instrumentation studies performed at the mine. These efforts provided two overarching conclusions concerning R ＆ P retreat mine planning and execution. The first was that there are four areas that should not be overlooked during R ＆ P retreat mining： topographic relief, multiple^seaPa str

关键词： Room and pillar Retreat mining Deep coverSafety Multiple seam

Geotechnical considerations for concurrent pillar recovery in close-distance multiple seams

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International Journal of Mining Science and Technology 2018年第1期28卷 21-27页

作者： Peter Zhang berk Tulu Morgan sears Jack Trackemas Ground Control branch NIOSHPittsburgh Mining Research Division Department of Mining Engineering West Virginia University

Room-and-pillar mining with pillar recovery has historically been associated with more than 25% of all ground fall fatalities in underground coal mines in the United *** risk of ground falls during pillar recovery increases in multiple-seam mining *** hazards associated with pillar recovery in multiple-seam mining include roof cutters, roof falls, rib rolls, coal outbursts, and floor *** pillar recovery is planned in multiple seams, it is critical to properly design the mining sequence and panel layout to minimize potential seam *** paper addresses geotechnical considerations for concurrent pillar recovery in two coal seams with 21 m of interburden under about 305 m of depth of *** study finds that, for interburden thickness of 21 m, the multiple-seam mining influence zone in the lower seam is directly under the barrier pillar within about 30 m from the gob edge of the upper *** peak stress in the interburden transfers down at an angle of approximately 20°away from the gob, and the entries and crosscuts in the influence zone are subjected to elevated stress during development and *** study also suggests that, for full pillar recovery in close-distance multiple-seam scenarios,it is optimal to superimpose the gobs in both seams, but it is not necessary to superimpose the *** the entries and/or crosscuts in the lower seam are developed outside the gob line of the upper seam,additional roof and rib support needs to be considered to account for the elevated stress in the multiple-seam influence zone.

关键词： Pillar recovery Room-and-pillar Retreat mining Multiple seam Mining sequence Pillar design

Effect of Laser Injection Seeder on Rotationally Resolved Spectra of benzonitrile

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Chinese Physics Letters 2010年第8期27卷 77-79页

作者：徐海峰 JOHNSON Philip M. sears Trevor J. Institute of Atomic and Molecular Physics 3ilin University~ Changchun 130012 Chemistry Department Stony Brook University Stony Brook NY 11974 USA Department of Chemistry Brookhaven National Laboratory Upton NY 11973 USA

High resolution lasers are necessary to derive the most information from molecular spectra. However, their use uncovers some photophysical processes that compromise the ability to resolve rotational structure. We study the influence of laser optical mode structure on the high resolution spectra of the S1 states of benzonitrile in a supersonic molecular beam using an Ar^＋ pumped cw ring dye laser which is amplified by a pulsed Nd： YA G laser. The latter could be operated either in one optical mode by injecting （seeding） its oscillator with a single mode diode laser, or with many optical modes by not using the seeder. Rotationally resolved lines are obtained when the oscillator of the YAG laser are operated in one single optical mode, but only a continuum is seen when the YAG laser has multiple modes. It is argued that the ac Stark effect is the most probable reason for broadening and blurring the rotational lines.

关键词： OPTICAL detectors INJECTION lasers NITRILES MOLECULAR spectra MOLECULAR beams ND-YAG lasers STARK effect

Developing New Applications based on Laser Additive Manufacturing of WC Cermets and WC Forming Alloys (Invited Paper)

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作者： (美)sears等

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中国激光 2009年第12期36卷 3245-3250页

作者： James W.sears Additive Manufacturing Laboratory South Dakota School of Mines & TechnologyQuad City Manufacturing LaboratoryWestern Illinois University501 E.St.Joseph St.Rapid City SD 5770

Laser additive manufacturing(LAM) of tungsten carbide metal matrix composites(MMCs) has been evaluated for surface modification of hot die forming tools,cutting edges,glass tooling,extrusion mandrels,and other abrasive wear *** work focuses on transitions from tool steels to MMCs through a single pass laser powder deposition *** related to the application of various metal powders and carbides used include surface hardness,porosity,cracking,and *** issues along with factory results that were obtained during this project are discussed.

关键词：激光添加剂碳化钨工具钢金属基复合材料

Coal rib response during bench mining: A case study

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International Journal of Mining Science and Technology 2018年第1期28卷 107-113页

作者： Morgan M.sears John Rusnak Mark Van Dyke Gamal Rashed Khaled Mohamed Michael Sloan Ground Control branch NIOSH Pittsburgh Mining Research Division

In 2016, room-and-pillar mining provided nearly 40% of underground coal production in the United *** the past decade, rib falls have resulted in 12 fatalities, representing 28% of the ground fall fatalities in *** coal *** of these 12 fatalities(75%) have occurred in room-andpillar *** objective of this research is to study the geomechanics of bench room-and-pillar mining and the associated response of high pillar ribs at overburden depths greater than 300 *** paper provides a definition of the bench technique, the pillar response due to loading, observational data for a case history, a calibrated numerical model of the observed rib response, and application of this calibrated model to a second site.

关键词： Deep cover bench mining Thick seam Retreat mining Rib response Rib support

Writing and erasing MYC ubiquitination and SUMOylation

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Genes & Diseases 2019年第4期6卷 359-371页

作者： Yingxiao Chen Xiao-Xin Sun Rosalie C.sears Mu-Shui Dai Departments of Molecular&Medical Genetics School of MedicineOHSU Knight Cancer InstituteOregon Health&Science University3181 SW Sam Jackson Park RoadPortlandOR 97239USA

The transcription factor c-MYC(MYC thereafter)controls diverse transcription programs and plays a key role in the development of many human *** develop multiple mechanisms to ensure that MYC levels and activity are precisely controlled in normal physiological *** a short half-lived protein,MYC protein levels are tightly regulated by the ubiquitin proteasome *** a dozen of ubiquitin ligases have been found to ubiquitinate MYC whereas a number of deubiquitinating enzymes counteract this *** studies show that SUMOylation and deSUMOylation can also regulate MYC protein stability and ***,evidence suggests an intriguing crosstalk between MYC ubiquitination and *** of the MYC ubiquitination-SUMOylation regulatory network may contribute to *** review is intended to provide the current understanding of the complex regulation of the MYC biology by dynamic ubiquitination and SUMOylation and their crosstalk.

关键词： deSUMOylating enzymes Deubiquitinating enzymes MYC SUMO SUMOylation Ubiquitination

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加州理工学院古根汉姆航空实验室的卡门岁月

力学进展 2011年第6期41卷 751-756页

作者： William R. sears Mabel R. sears 张静(译) 不详中国力学学会

加利福尼亚理工学院的古根汉姆航空实验室（Guggenheim Aeronautics Laboratory at the California Institute of Technology，GALCITl白20世纪20年代晚期始建直至1942年一直是西奥多．冯．卡门指导的．在这段相对不长的时期内，尤其是... 详细信息

加利福尼亚理工学院的古根汉姆航空实验室（Guggenheim Aeronautics Laboratory at the California Institute of Technology，GALCITl白20世纪20年代晚期始建直至1942年一直是西奥多．冯．卡门指导的．在这段相对不长的时期内，尤其是流体力学方面，GALCIT是享誉国际的科研中心与培训基地．GALCIT吸引了众多世界上杰出的流体力学专家来这里做短期或长期的访问学者，

关键词：冯.卡门加州理工学院实验室航空加利福尼亚理工学院流体力学科研中心

Oral eplerenone for the management of chronic central serous chorioretinopathy

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International Journal of Ophthalmology(English edition) 2015年第2期8卷 310-314页

作者： Rishi P Singh Jonathan E sears Rumneek bedi Andrew P Schachat Justis P Ehlers Peter K Kaiser Cole Eye Institute 9500 Euclid Avenue i-32 Cleveland Clinic

AIM: To examine eplerenone(Inspra, Pfizer), a mineralocorticoid receptor antagonist, as a treatment option for chronic central serous chorioretinopathy(CSCR).METHODS: A retrospective consecutive case series was conducted for patients receiving oral eplerenone for chronic CSCR. At baseline and each follow-up visit,spectral domain optical coherence tomography(SD-OCT)imaging was performed, including manual measurements of the height and diameter size of subretinal fluid. The primary outcome measure was the reduction in subretinal fluid following initiation of ***: A total of 17 eyes of 13 patients treated with25 and 50 mg of oral eplerenone per day were *** fluid(SRF) decreased over time following eplerenone therapy(P = 0.007 and P =0.002, diameter and height respectively). Maximum SRF height decreased from a mean of 131.5 μm at baseline to 15.3 μm at day181+. SRF diameter decreased from an average of 2174.4μm at baseline to 46.9 μm at day 181 +. Log MAR visual acuity improved from 0.42(Snellen equivalent: 20/53) at baseline to 0.29(Snellen equivalent: 20/39) at day 181 +(P = 0.024). Central subfield thickness(CST) decreased from 339.5 μm at baseline to 270.3 μm at day 181+(P = 0.029).CONCLUSION: Eplerenone therapy resulted in significant anatomic and visual improvements in eyes with chronic CSCR.

关键词： central serous chorioretinopathy central serous retinopathy eplerenone subretinal fluid