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Solvent desorption from carbon beds in ducted and nonducted laboratory fume hoods

Applied Occupational and Environmental Hygiene 1991年第7期6卷 592-597页

作者： Keimig, Scott D. Esmen, Nurtan A. Erdal, Serap Sansone, Eric B. Environmental Safety Department Catholic University of America District of Columbia 20064 United States Department of Industrial Environmental Health Sciences Graduate School of Public University of Pittsburgh Pittsburgh PA 15261 United States Environmental Control and Research Program National Cancer Institute—Frederick Cancer Research and Development Center Frederick MD 21702-1201 United States

To assess the magnitude and speed of desorption of adsorbed vapors from commercial carbon beds used in laboratory hoods, known quantities of organic solvents were evaporated in one ducted (i.e., exhausted to the outside) and two nonducted (i.e., recirculating) laboratory fume hoods. The air downstream of the filters was then sampled and analyzed. Benzene (BZ), carbon tetrachloride (CT), and ethyl acetate (EA) were individually volatilized at room temperature in a ducted chemical fume hood at 6, 4, and 5 ppm, respectively. BZ and EA were released twice;CT was released four times. The total amount of vapor desorbed, as a percentage of the mass released, ranged from 10 percent for the first BZ release to 100 percent for the fourth CT release. BZ, CT, and n-hexane (HX) were simultaneously volatilized in nonducted laboratory fume hoods at 10, 50, and 125 ppm, respectively, over six 4-hour periods, with each 4-hour release followed by 4 hours of vapor-free air (88 hours of vapor-free air after the sixth release). In that time period, about 15 percent of the BZ, 50 percent of the HX, and 75 percent of the CT desorbed. A theoretical solution of the desorption phenomenon indicated that the logarithm of the concentration of the desorbing vapor should be inversely proportional to the time after adsorption. The regression coefficients for the experimental data ranged from 0.62 to 0.97, with 6 of 12 equal to or greater than 0.90 and 10 of 12 equal to or greater than 0.85. The experimental results were consistent with theory. Rapid and substantial desorption from previously unused carbon beds was observed. © 1991 Taylor & Francis Group, LLC.

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STRUCTURAL-ANALYSIS METHODS FOR LIGHTWEIGHT METALLIC CORRUGATED CORE SANDWICH PANELS SUBJECTED TO BLAST LOADS

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NAVAL ENGINEERS JOURNAL 1991年第4期103卷 134-136页

作者： WIERNICKI, CJ LIEM, F WOODS, GD FURIO, A WHIDDON, WD SMITH, MA PACKARD, WT Christopher J. Wiernickiis the director of the Structures and Materials Division of Designers and Planners Inc. He has over 10 years of experience in marine structural design and advanced material product development. He received a B.S. degree in civil engineering from Vanderbilt University and M.S. degrees from both George Washington University and Massachusetts Institute of Technology. He is a registered professional engineer and is a member of ASNE SNAME and SAMPE. Franz Liemis a senior structural engineer of ASTECH. He has over 18 years of experience in structural engineering. He received M.S. degrees in civil/structural engineering from Carollo Wilhelmina University in West Germany. He is a registered professional engineer. Gregory D. Woodsis the Naval Sea Systems Command's lightweight metallic structures program manager. Until recently a naval architect in the Structural Integrity Application Division he currently works in the Amphibious Auxiliary and Support Ship Branch. He received a B.S. degree in mechanical engineering from Tennessee State University with additional graduate level course work at the NavSea Institute. Anthony J. Furiois the program manager for lightweight metallic structures in the Ship Structure Division of the David Taylor Research Center. He has over 19 years of experience in ship structure research and light weight metallic development for U.S. Navy fleet applications. He received a B.S. in civil engineering from Long Island University and a M.S. in ocean engineering from Stevens Institute of Technology.

Since the early 1980s, the U.S. Navy, in conjunction with industry, has continued to develop and test innovative lightweight structural concepts with the purpose of seeking alternative replacements for conventional plate beam metallic structures. One commercially available concept currently under investigation is lightweight metallic corrugated core sandwich panels. This paper presents both elastic and plastic design methods for lightweight metallic corrugated core sandwich panels subjected to air blast loading. The equations presented in this paper, while not a complete solution to the complicated dynamic, elastic plastic phenomena of blast wave-rigid body interaction, are offered as a set of relatively simple analytical expressions that can be used in preliminary design. Because of the closed form nature of the equations the designer has the capability to quickly identify the most important parameters effecting the response of lightweight metallic corrugated core sandwich panels to air blast loads.

关键词： Shipbuilding Materials

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FULL-WAVE SOLUTION OF DIELECTRIC LOADED WAVE-GUIDES AND SHIELDED MICROSTRIPS UTILIZING FINITE-DIFFERENCE AND THE CONJUGATE-GRADIENT METHOD

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INTERNATIONAL JOURNAL OF MICROWAVE AND MILLIMETER-WAVE COMPUTER-AIDED ENGINEERING 1991年第4期1卷 346-357页

作者： NARAYANAN, V MANELA, M LADE, RK SARKAR, TK Department of Electrical and Computer Engineering Syracuse University Syracuse New York 13244-1240 Viswanathan Narayanan was born in Bangalore India on December 14 1965. He received the BE degree in Electronics and Communications from B.M.S. College of Engineering Bangalore in 1988. He joined the Department of Electrical Engineering at Syracuse University for his graduate studies in 1989 where he is currently a research assistant. His research interests are in microwave measurements numerical electromagnetics and signal processing. Biographies and photos are not available for M. Manela and R. K. Lade. Tapan K. Sarkar (Sf69-M'76-SM'X1) was born in Calcutta. India on August 2 1948. He received the BTech degree from the Indian Institute of Technology Kharagpur India in 1969 the MScE degree from the University of New Brunswick Fredericton Canada in 1971. and the MS and PhD degrees from Syracuse University. Syracuse NY in 1975. From 1975-1976 he was with the TACO Division of the General Instruments Corporation. He was with the Rochester Institute of Technology (Rochester NY) from 1976-1985. He was a Research Fellow at the Gordon Mckay Laboratory Harvard University Cambridge MA from 1977 to 1978. He is now a Professor in the Department of Electrical and Computer Engineering Syracuse University. His current research interests deal with numerical solutions of operator equations arising in electromagnetics and signal processing with application to system design. He obtained one of the “ best solution” awards in May 1977 at the Rome Air Development Center (RADC) Spectral Estimation Workshop. He has authored or coauthored more than 154 journal articles and conference papers and has written chapters in eight books. Dr. Sarkar is a registered professional engineer in the state of New York. He received the Best Paper Award of the IEEE Transactions on Electromagnetic Compatibility in 1979. He was an Associate Editor for feature articles of the lEEE Antennas arid Propagation Sociefy Newsletter and was

Dynamic analysis of waveguide structures containing dielectric and metal strips is presented. The analysis utilizes a finite difference frequency domain procedure to reduce the problem to a symmetric matrix eigenvalue problem. Since the matrix is also sparse, the eigenvalue problem can be solved quickly and efficiently using the conjugate gradient method resulting in considerable savings in computer storage and time. Comparison is made with the analytical solution for the loaded dielectric waveguide case. For the microstrip case, we get both waveguide modes and quasi-TEM modes. The quasi-TEM modes in the limit of zero frequency are checked with the static analysis which also uses finite difference. Some of the quasi-TEM modes are spurious. This article describes their origin and discusses how to eliminate them. Numerical results are presented to illustrate the principles.

关键词： Waveguides

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Two types of global environmental change. Definitional and spatial-scale issues in their human dimensions

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Global Environmental Change 1990年第1期1卷 14-22页

作者： Turner II, B.L. Kasperson, Roger E. Meyer, William B. Dow, Kirstin M. Golding, Dominic Kasperson, Jeanne X. Mitchell, Robert C. Ratick, Samuel J. The authors are with The Earth Transformed Program Graduate School of Geography Center for Technology Environment and Development Worcester MA 01610 United States Jeanne X. Kasperson is also with the Alan Shaun Feinstein World Hunger Program Brown University Providence RI 02912 United States

Clarification of several issues in the human dimensions of global environmental change is essential to the creation of a balanced research agenda. Global environmental change includes both systemic changes that operate globally through the major systems of the geosphere-biosphere, and cumulative changes that represent the global accumulation of localized changes. An understanding of the human dimen sions of change requires attention to both types through research that integrates findings from spatial scales ranging from the global to the local. A regional or meso-scale focus represents a particularly promising avenue of approach. © 1990.

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AEGIS DISPLAY SYSTEM MAP DATA-BASE

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NAVAL ENGINEERS JOURNAL 1990年第3期102卷 138-145页

作者： PANTAZOPOULOS, MV BARKER, RG SLIMMER, RL Michael V. Pantazopoulos:has been a physicist at the Naval Surface Warfare Center in Dahlgren Va. since August 1985. He received his B.S. and M.S. in physics from Emory University. He has been a member of the Aegis Display System Group in the Aegis Combat Direction Systems Branch since 1985. This group maintains the Aegis coastline map data base and most of his work has been in the developing analyzing and testing of the digital map data bases. R. Gordon Barker:has been a mathematician at the Naval Surface Warfare Center in Dahlgren Va. since 1964. He received a B.S. from the University of Virginia and did his graduate study at Princeton University. He has been a member of the Aegis Display System Group since 1982. During the development of the Mark 1 Aegis Display System Map Data Base Mr. Barker wrote the program to perform the “data thinning” of the map data. In order to support the system upgrades in progress Mr. Barker developed a tool to polygonize the map data. Rebecca L. Slimmer:has been a computer scientist at the Naval Surface Warfare Center in Dahlgren Va. since 1984. She received her B.S. from Sam Houston State University. She has been a member of the Aegis Display System Group since 1984. Her work has included maintaining and upgrading the Aegis Display System Map Data Base Generation Computer Program participation in Defense Mapping Agency data base evaluations and development of a map data base for the Naval Intelligence Processing System in a joint effort with M. Pantazopoulos. She currently serves as the point of contact for the Aegis Display System Map Data Base.

The Aegis Combat System is an advanced integrated combat system engineered specifically for Ticonderoga class cruisers. An essential component of this system is the Aegis Display System (ADS), which displays real-time ownship and fleet tactical information. Integral to the ADS is the display of coastline map data to provide geographic perspective to the tactical picture. The purpose of this paper is to describe the design and implementation of the map data base into the ADS. The original ADS equipment limited the number of coastline points which could be displayed at one time, thus leading to the development of several data thinning techniques. The requirements for real-time maps also motivated the introduction of some novel features into the data base architecture. The data base was required to support nine range scales and yet maintain the same approximate density of points throughout the entire world. To accomplish this, the data were partitioned into “windows,” with a uniform size based on distance rather than an angular measurement. This resulted in windows approximately the same size in area, but with a longitudinal width which increases as polar latitudes are approached. The number of data points was then reduced by applying several thinning algorithms so that the desired point densities were reached. The windows were organized into four separate data subbases, each with a different window size but a similar point density. This scheme allows coverage of an entire display area with at most four windows at any range scale. The display speed was optimized by exploiting the Aegis Combat System's use of orthographic projection from the earth's surface to the display plane. This type of projection permits integer arithmetic in the transformation projection equations when the data points are stored as X,Y,Z earth-centered coordinates instead of as latitude and longitude. This results in substantially faster map processing and display times, thereby allowing the ADS

关键词： Display Devices

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Review: AREUEA Journal

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Journal of Planning Education and Research 1989年第2期8卷 113 - 114页

作者： Richard B. Peiser Richard B. Peiser is Associate Professor of Urban and Regional Planning at the University of Southern California Los Angeles. He directs the Graduate Real Estate Development Program in the School of Urban and Regional Planning

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Constructing a response to responses.

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Journal of learning disabilities 1989年第5期22卷 309-313页

作者： Rettinger, V. Waters, W. Poplin, M.S. Virginia Rettinger is a doctoral student at Claremont Graduate School and is a teacher in the Teacher Education Program. She received her master's degree from Cal State at Northridge and has taught high school social studies for many years. Her research interests include studies of student motivation theory gender differences in learning and constructivist curriculum development. William Waters received his master's degree from the Claremont Graduate School in 1987 and teaches high school English remedial English and English as a Second Language at Etiwanda High School in Cucamonga California. He also teaches at the Claremont Graduate School and writes in the area of constructivism and secondary language learning. Mary Simpson Poplin received her PhD from The University of Texas at Austin in education. She is associate professor of education and director of teacher education at the Claremont Graduate School. In addition she is director of The Center for Schools in Transformation the goal of which is the development of joint school-university partnerships. Her research interests include learning disabilities constructivist learning theory feminist theory school transformation and teacher education. Address: Mary Poplin Faculty in Education Harper Hall Claremont Graduate School Claremont CA 91711-6160.

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Burnout and Counselor Practitioner Expectations of Supervision

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Counselor Education and Supervision 1989年第3期28卷 234-241页

作者： DAVIS, ALAN H. SAVICKI, VICTOR COOLEY, ERIC J. FIRTH, JAMES L. Director of student support services Alan H. Davis is director of student support services Student Development Center Eastern Oregon State College LaGrande. Professors Victor Savicki and Eric J. Cooley are professors in the Department of Psychology Western Oregon State College Monmouth. Professor of education in the Graduate Program in Counseling James L. Firth is a professor of education in the Graduate Program in Counseling at Oregon State University Corvallis.

The authors assessed counselor expectations of supervision and counselor burnout. A sample consisting of 120 members of the Oregon Personnel and Guidance Association completed the Maslach Burnout Inventory (MBI) and t...

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COMPARATIVE-ASSESSMENT OF UNITED-STATES AND FOREIGN BUOY TENDERS

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NAVAL ENGINEERS JOURNAL 1989年第4期101卷 136-136页

作者： KEHOE, JW BROWER, KS TUTTLE, JG Capt. James W. Kehoe Jr. USN (Ret.):is well known for his work in comparative naval architecture studies of U.S. and foreign warship design practices for which he received the American Society of Naval Engineer's Gold Medal Award for 1981 and the Legion of Merit in 1982. He received the ASNE “Jimmie” Hamilton Award for 1983. He is currently a partner in Spectrum Associates Inc. Arlington Virginia. Prior to his retirement in 1982 his naval career included sea duty aboard three destroyers and three aircraft carriers including command of a destroyer and engineer officer of an aircraft carrier. Kenneth S. Brower:is a partner in Spectrum Associates Inc. a naval engineering firm which he founded in 1978 which is currently engaged in the design of naval ships comparative naval architecture studies and the development of ship design synthesis computer programs. A graduate in naval architecture from the University of Michigan he has contributed to the design of numerous warships and merchant ships as well as several frigate designs for foreign military sales. Mr. Brower has been the author or coauthor of numerous technical studies and articles. He received the ASNE “Jimmie” Hamilton Award for 1983. LCdr. John G. Tuttle USCG:is a graduate of the New York Maritime College and the Naval Construction and Engineering Program at MIT. Prior to joining the Coast Guard he was a naval architect for the Navy. He has served in the Marine Safety Offices in New Orleans and Boston. He has also been an instructor in the marine engineering program at the Coast Guard Academy. He was a project officer in the Office of R&D supporting buoy tender and patrol boat acquisitions. He is currently assigned as technical manager of the Buoy Tender Replacement Project in the Office of Acquisition at USCG Headquarters.

The paper reports the results of a comparative study of seven modern foreign buoy tenders and two older U.S. buoy tenders that was conducted by the U.S. Coast Guard as part of its current project to replace its older medium size (WLM) and large seagoing (WLB) buoy tenders. As part of the assessment, the authors visited the foreign ships to observe them conducting buoy tending operations, to review engineering design data, and to discuss buoy tender design, technology and operations with the cognizant operating authorities. The buoy tenders included the Canadian 4,800-ton Type 1100 and 2,800-ton Type 1050, the British 2,900-ton Mermaid , the Swedish 1,200-ton Baltica , the Norwegian 1,100-ton Skomvaer , the Dutch 700-ton Rotterdam , and the Italian 600-ton MIF. The U.S. buoy tenders included the Coast Guard 470-ton, 157-foot WLM and 1,000-ton, 180-foot WLB (SLEP), which were also visited and included in the study for comparative purposes. The study's objectives were to identify design practices and technology incorporated in the foreign buoy tenders that the U.S. Coast Guard could adapt in designing future buoy tenders and to determine if any foreign buoy tender design meets the Coast Guard requirements for WLB and WLM replacements. The design characteristics, technology, and unique features of each buoy tender are described and compared. Lessons learned from the study which could be beneficial in the design of future Coast Guard buoy tenders are identified. Finally, the capabilities of the foreign buoy tenders are assessed in relation to current Coast Guard requirements.

关键词： Naval Vessels

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BOTTOM BOUNCE ARRAY SONAR SUBMARINE (BBASS)

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NAVAL ENGINEERS JOURNAL 1989年第5期101卷 59-72页

作者： JACKSON, HA NEEDHAM, WD SIGMAN, DE USN (RET.) Capt. Harry A. Jackson USN (Ret.) is a graduate of the University of Michigan in naval architecture and marine engineering and completed the General Electric Company's 3-year advanced engineering course in nuclear engineering. He has been an independent consulting engineer and participated in projects involving deep submergence waste disposal water purification and submarine design both commercial and government. Cdr. William D. Needham USN is currently assigned as the repair officer of USS Hunley (AS-31) in Norfolk Virginia. He received a regular commission through NROTC at Duke University where he graduated magna cum laude in mechanical engineering. Selected for the Nuclear Power Program he served as a division officer on the USS Grayling (SSN-646) as the production training assistant at the MARE Prototype Reactor in New York and as blue crew engineer of the USS Nathan Hale (SSBN-623) where he completed the requirements to be designated qualified for command of submarines. Following line transfer to the EDO community in 1981 he completed a tour as nuclear repair officer (Code 310) at Norfolk Naval Shipyard and earned master of science in materials science and ocean engineer's degrees at MIT. His awards include the Meritorius Service Medal Navy Commendation Medal Navy Achievement Medal Spear Foundation Award and the Vice Admiral C.R. Bryan Award. Cdr. Needham also holds a master of arts degree in business management from Central Michigan University. Capt. Jackson was technical director of Scorpion Search Phase II. The on-site investigation included descending over 12 000 feet to the bottom of the ocean. He was also supervisor of one of the Navy's largest peacetime shipbuilding and repair programs. His responsibilities included supervision of design production and contract administration. Capt. Jackson was third from the top in managaement of a major shipyard and responsible for design material procurement work order and financial control of two major surface ship prototypes as well a

Anticipated technological advances in the quieting of potential adversary submarines mandate the use of increasingly effective detection systems for U.S. ASW forces. Based on the assumptions that sonar will continue to be the primary means of detection and that the effectiveness of each individual sonar element will not change markedly, one must increase the projected area of the sonar array to improve its capability. The primary SSN mission of anti-submarine warfare will hence require increasing the hull area devoted to the primary sonar detection system. A revolutionary hull form is proposed that maximizes the area available for this purpose. The advantages and disadvantages of this hull form are discussed and feasibility study level design parameters and arrangements presented.

关键词： Submarines

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