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Laboratory results of a 3rd generation roof bolter canopy air curtain for respirable coal mine dust control

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International Journal of Coal Science & Technology 2019年第1期6卷 15-26页

作者： W.R.Reed G.J.Joy M.Shahan S.klima G.Ross Centers for Disease Control anti Prevention National Institute for Occupational Safety and Health 626 Cochrans Mill Rd.PittsburghPA 15236USA J.H Fletcher & Co. Inc.402 High St.HuntingtonWV 25705USA

Testing was completed on an earlier roof bolter CAC that used slots to provide a perimeter airflow. NIOSH tested it due to its unique design that differed from canopies that provided uniform airflow. Based upon NIOSH recommendations from the earlier testing, a 3rd generation roof bolter CAC has been developed by J.H. Fletcher & Co. The changes to this CAC involve design modifications to the plenum outlets, using a single row of outlets on the perimeter and a different material for the plenum. This laboratory testing was a continuation of the original perimeter slotted CAC design. Using gravimetric and instantaneous sampling of respirable dust concentrations underneath and outside of the CAC. the laboratory testing was completed using three different blower fans that delivered differing airflows. The maximum plenum airflow velocities ranged from 2.34 to 3.64 m/s (460-716 fpm). Results showed plenum respirable dust concentrations ranging from 34.6% to 49.3% lower than respirable dust concentrations outside the plenum protection zone, thus showing an improvement in protection for the roof bolter operators.

关键词： Roof bolter Respirable dust Canopy air curtain Coal mining

A field study of a roof bolter canopy air curtain(2nd generation)for respirable coal mine dust control

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International Journal of Mining Science and Technology 2019年第5期29卷 711-720页

作者： W.R.Reed S.klima M.Shahan G.J.H.Ross K.Singh R.Cross T.Grounds CDC NIOSH Pittsburgh Mining Research DivisionPittsburghPA 15236USA Fletcher&Co. HuntingtonWV 25705USA Prairie State Generating Company LLC Lively GroveIL 62257USA

A 2nd generation roof bolter canopy air curtain(CAC)design was tested by National Institute for Occupational Safety and Health(NIOSH)at a Midwestern underground coal *** the study,the roof bolter never operated downwind of the continuous *** a combination of personal Data Rams(pDR)and gravimetric samplers,the dust control efficiency of the roof bolter CAC was *** evaluation was determined using three methods:(1)comparing roof bolter operator concentrations underneath the CAC to roof bolter concentrations outside the CAC,(2)comparing roof bolter operator concentrations underneath the CAC to the concentrations at the rear of the bolter,and finally,(3)using the gravimetric data directly underneath the CAC to correct roof bolter operator concentrations underneath the CAC and comparing them to the concentrations at the rear of the *** 1 dust control efficiencies ranged from 53.9%to 60.4%.Method 2 efficiencies ranged from 150.5%to 52.2%,and Method 3 efficiencies ranged from 40.7%to 91%.Reasons for negative and low dust control efficiencies are provided in this paper and include:incorrect sampling locations,large distance between CAC and operator,and contamination of intake air from line *** dust concentrations encountered during the testing made it difficult to discern whether differences in concentrations were due to the CAC or due to variances inherent in experimental dust ***,the analyses,especially the Method 3 analysis,show that the CAC can be an effective dust control device.

关键词： Coal Roof bolter Respirable dust Underground mining

Field study results of a 3rd generation roof bolter canopy air curtain for respirable coal mine dust control

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International Journal of Coal Science & Technology 2020年第1期7卷 79-87页

作者： W.R.Reed M.Shahan S.klima G.Ross K.Singh R.Cross T.Grounds NIOSH PittsburghPA.USA J.H.Fletcher&Co. Huntington WVUSA Prairie State Generating Company LLC Lively GroveILUSA

A 3rd generation roof bolter canopy air curtain(CAC)has been developed and constructed by ***&Co.,*** with the previous generation of the CAC,this design uses the principle of providing uniform airflow across the canopy area as recommended by the National Institute for Occupational Safety and *** new modifications include a plenum that is constructed of a single flat aluminum plate,smaller-diameter airflow openings,and a single row of perimeter nozzles designed to prevent mine air contaminated by respirable dust from entering the CAC protection *** testing was conducted on this new 3rd generation design showing reductions in coal mine respirable dust exposure for roof bolter *** control efficiencies for the CAC for the left bolter operator(intake side)ranged from approximately 26%–60%,while the efficiencies for the CAC for the right bolter operator(return side)ranged from 3%to 47%.

关键词： Roof bolter Respirable dust Coal mining Canopy air curtain

Using yttrium as an indicator to estimate total rare earth element concentration:a case study of anthracite-associated clays from northeastern Pennsylvania

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International Journal of Coal Science & Technology 2020年第4期7卷 652-661页

作者： Xiaojing Yang Daniel Kozar Daniel Gorski Anthony Marchese James Pagnotti Rusty Sutterlin Mohammad Rezaee Mark S.klima Sarma V.Pisupati John and Willie Leone Family Department of Energy and Mineral Engineering and the EMS Energy Institute Center for Critical MineralsThe Pennsylvania State University110 Hosier BuildingUniversity ParkPA 16802USA Texas Mineral Resources Corporation.539 El Paso St Sierra BlancaTX 79851USA Pagnotti Enterprises 46 Public SquareWilkes-BarrePA 18701USA Inventure Renewables Inc161625th Avenue.TuscaloosaAL 35401USA

This study demonstrated using yttrium(Y)as an indicator to estimate the total rare earth element and Y contents(REY)in coal-associated samples and to facilitate selection of samples with high REY assays in a fast and inexpensive *** than 10 anthracite-associated samples were collected from each of three Pennsylvanian sites(sites B,J and C)based on Thorium gamma ray logging suggesting high REY *** samples from each site were analyzed by ICP-MS to determine the rare earth distribution patterns and to establish the site-specific linear equations of Y and *** Y contents of the remaining samples were measured by a portable X-ray fluorescence analyzer,and the REY values were estimated based on the site-specific linear equation developed earlier.R-squared values above 0.70 were obtained for all the estimation equations from all three sites on both a whole sample basis and an ash ***,ash content has been widely used as an indicator of high REY *** may not be applicable for a specific *** B in this study is an example where ash contents could not be statistically correlated with REY,so using Y for estimation is more *** demonstrated sample screening process is suitable for samples from sites that share more similar distribution patterns(either MREY or LREY or HREY)as well as for samples from sites that share multiple distribution patterns(LREY/MREY/HREY)depending on the desirable *** demonstrated process lowers the analytical cost from$70 to 80 dollars per sample to$10-15 per sample while significantly reducing the processing time and acid consumption for ICP *** is particularly true when a relatively large sample size is involved,for example,100 samples from one site analyzed by ICP-MS/OES.

关键词： Rare earth elements XRF analysis Correlations Prediction ICP analysis

Study of Deformation Coating for Sheets by Using Tensile Test

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Journal of Surface Engineered Materials and Advanced Technology 2015年第2期5卷 73-83页

作者： Milan Dvorak Emil Schwarzer Milos klima BUT Faculty of Mechanical EngineeringIMTBrnoCzech Republic MU Faculty of SciencePF MUBrnoCzech Republic

This article focuses on the study of the defined values of tensile strain and the effect of low temperature plasma adhesion selected coatings on steel samples using a tensile testing flat test bars. Samples were made by machining and welding technologies. The flat test bars were tested by pulling on a test rig UPC 1200. Part of the samples was treated on the surface prior to coating by a tensile test, second base coat and with a final coat continuous multi plasma system. The selected test samples were determined from the tensile test of the material characteristics apparent from the tensile diagrams. The examined samples were fitted top and base coat. Another group was the KTL basis. The presented graphs show the dependence of the strength on elongation of a sample according to DIN EN ISO 6892-2. The samples were then examined under a stereo microscope SCHUT brand, type SSM-E in the laboratory to conduct coating on a steel sheet at the moment of total violation sectional samples. The base layer, in which the temperature ranges from 160°C - 180°C, was applied by electrophoresis method.

关键词： Tensile Test Sheet with Coating Adhesion of Coating Multi-Jet Plasma System

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生物染色剂和荧光染料做为对虾标志的评估

水产科学 1992年第11期11卷 26-29页

作者： Edward F.klima 马莹

我们做了一些室内实验,试图发现一些在标志回捕实验中能够分辨放流对虾群体的标志物质,以便估算种群的生长率和死亡率。我们通过注射各种生物染色剂和荧光染料,找到了可做为对虾标志的组合标志法。这些标志是永久的,并且不影响对虾的存活。

关键词：染色剂荧光染料对虾标志

生物染色剂和荧光染料做为对虾标志的评估(续)

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水产科学 1992年第12期11卷 22-25页

作者： Edward F.klima 马莹

1.双注射的标志方法双注射法是由两次单独的注射组成的,首先进行初级染色,然后进行次级染色。按前面所述的方法将初级染料的水溶液——固绿或台盼兰注射入实验对虾体内,次级染色物质用1或2ml结核菌素注射器25或27号针头注射。

关键词：染色剂荧光染料对虾标志

Active Rifting Hazards at Tendaho Dam and Irrigation Site,Afar Depression,NE Ethiopia

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地学前缘 2009年第S1期16卷 42-42页

作者： Nehemia Solomon Beyene Kurt klima Institute for Applied Geosciences Graz University of Technology

The proposed Tendaho Reservoir and Irrigation site is located at the center of the Afar Depression where the Main Ethiopian Rift(MER),the Red Sea Rift and the Gulf of Aden Rift join at the extensional triple *** entire irrigation scheme and the reservoir area lie within the Tendaho Graben and at the west horst of the Graben(Tendaho Goba’ad Dis-

关键词： geohazards rifting dam and reservoir tectonics Afar depression

Applications of abstract algebra with Maple and MATLAB 2nd ed.

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