We simulated the flow field and flame propagation near top dead center in a generic large-bore internal combustion engine using the COYOTE computer program, which is based on the full Navier-Stokes equations for a fluid mixture. The combustion chamber is a right circular cylinder, and the main charge is uniformly premixed. The calculations are axisymmetric. The results illustrate the differences in flow patterns, flame propagation, and thermal NO production between ignition with a spark plug and with a small prechamber. In the spark-ignited case, the flame propagates away from the spark plug approximately as a segment of a spherical surface, just as expected. With the prechamber, a high speed jet of hot combustion products shoots into the main chamber, quickly producing a large flame sheet that spreads along the piston face. The prechamber run consumes all of the fuel in half the time required by the spark-ignited case. The two cases produce comparable amounts of thermal NO at the end of fuel combustion.

This progress report summarizes the work performed for the October-December 1993 period on the development and evaluation of a manganese oxide adsorbent. Most of efforts at the early stage of the project have been directed toward screening and selection of granular activated carbon (GAC) samples for use as the substrate in preparing the composite adsorbent and in the evaluation of the Mn oxide coating on the GAC surface. Tables are provided in this report which summarize GAC characteristics and which evaluate MnO{sub 2} coating efficiency for three replicates at three different extraction times. Plans for future experiments are briefly discussed.

Effects of variations in natural gas composition on autoignition of natural gas under direct-injection (DI) diesel engine conditions were studied experimentally in a constant-volume combustion vessel and computationally using a chemical kinetic model. Four fuel blends were investigated: pure methane, a capacity weighted mean natural gas, a high ethane content natural gas, and a natural gas with added propane typical of peak shaving conditions. Experimentally measured ignition delays were longest for pure methane and became progressively shorter as ethane and propane concentrations increased. At conditions characteristic of a DI compression ignition natural gas engine at Top Dead Center (CR=23:1, p = 6.8 MPa, T = 1150K), measured ignition delays for the four fuels varied from 1.8 ms for the peak shaving and high ethane gases to 2.7 ms for pure methane. Numerically predicted variations in ignition delay as a function of natural gas composition agreed with these measurements.

The National Synchrotron Light Source Safety Analysis Reports (1),(2),(3), BNL reports {number_sign}51584, {number_sign}52205 and {number_sign}52205 (addendum) describe the basic Environmental Safety and Health issues associated with the department`s operations. They include the operating envelope for the Storage Rings and also the rest of the facility. These documents contain the operational limits as perceived prior or during construction of the facility, much of which still are appropriate for current operations. However, as the machine has matured, the experimental program has grown in size, requiring more supervision in that area. Also, machine studies have either verified or modified our knowledge of beam loss modes and/or radiation loss patterns around the facility. This document is written to allow for these changes in procedure or standards resulting from their current mode of operation and shall be used in conjunction with the above reports. These changes have been reviewed by NSLS and BNL ES&H committees and approved by BNL management.

A chemical kinetic model has been developed which describes pyrolysis, ignition and oxidation of many small hydrocarbon fuels over a wide range of experimental conditions. Fuels include carbon monoxide and hydrogen, methane and other alkane species up to n-butane, ethylene, propene, acetylene, and oxygenated species such as methanol, acetaldehyde and ethanol. Formation of some larger intermediate and product species including benzene, butadiene, large olefins, and cyclopentadiene has been treated in a semi-empirical manner. The reaction mechanism has been tested for conditions that do not involve transport and diffusional processes, including plug flow and stirred reactors, batch reactors and shock tubes. The present kinetic model and its validation differ from previous reaction mechanisms in two ways. First, in addition to conventional combustion data, experiments more commonly associated with chemical engineering problems such as oxidative coupling, oxidative pyrolysis and steam cracking are used to test the reaction mechanism, making it even more general than previous models. In addition, H atom abstraction and some other reaction rates, even for the smaller C{sub 2}, C{sub 3} and C{sub 4} species, are treated using approximations that facilitate future extensions to larger fuels in a convenient manner. Construction of the reaction mechanism and comparisons with experimental …

Addition of hydroperoxy-alkyl radicals to molecular oxygen leads to chain branching in autoignition and engine knock, and in low temperature oxidation of paraffins. Rate constants and product channels for reaction of hydroperoxy-propyl radicals with O{sub 2} are estimated using thermodynamic properties, bimolecular quantum Kassel analysis and transition state theory. Thermochemistry of relevant molecules and radicals is estimated using group additivity and bond dissociation groups for radicals. Results show that rates of the hydroperoxy-propyl radical addition to O{sub 2} are near their high pressure limits at {ge} 1 atm. Main products at 1--15 atm are stabilization, reverse reaction to hydroperoxy-propyl + O{sub 2} and alkyl carbonyl + OH. Reactions of the stabilized adducts, dissociation rates and product channels are estimated using unimolecular quantum Kassel analysis, because stabilization is the most important hydroperoxy-propyl radical + O{sub 2} product channel. Below 700 K, the stabilized peroxy adducts react primarily to hydroperoxy-carbonyl + OH, products which lead to chain branching. Above 700K, the stabilized peroxy adducts react primarily to hydroperoxy-propyl radical + O{sub 2}, initial reactants, which inhibits the overall oxidation. This switchover in channels correlates well observed negative temperature coefficient behavior for propane oxidation. Rate expressions for reaction of each of the three …

In this paper the author computes the radiative power losses which would be expected from the beam-plasma neutron source, which is proposed as a neutron source for doing accelerated end-of-life testing of fusion reactor materials. The source is based on a high density tritium target, bombarded with a deuterium beam of energy 120 to 150 keV. Oxygen was observed to be a major source of power loss for beam injection into the 2XIIB device, and the author considers that problem here. Oxygen impurities are a small component of the beam. The analysis indicates that higher charge states are reached in this device, resulting in less power radiation from oxygen impurities, and the beam is expected to attain higher purity levels at pulse lengths in the seconds range, than was observed in the past for millisecond pulse lengths.

We discuss preliminary results of a search for top quarks using their decays in two di-lepton, with the D0 detector at Fermilab. The present analysis has been optimized to search for a top with mass near 100{sub c{sup 2}}/{sup GeV}, consistent with published limits. In the event sample corresponding to an integrated luminosity of 15pb{sup {minus}1} we observe two events passing all selection cuts. The number of events observed is consistent with the expected number of background events. Consequently, we do not claim the observation of a top decay in the present event sample. We note however, that the kinematic properties of one of the events appear to be far removed from known backgrounds. We discuss the event and show results of the mass likelihood analysis when applied to this event.

Review of SRT-CMA-930039, ``Nuclear Criticality Safety Evaluation (NCSE): DWPF Melter-Batch 1,`` December 1, 1993, has been performed by the Savannah River Technical Center (SRTC) Applied Physics Group. The NCSE is a criticality assessment of the Melt Cell in the DWPF. Additionally, this pertains only to Batch 1 operation, which differs from batches to follow. Plans for subsequent batch operations call for fissile material in the Salt Cell feed-stream, which necessitates a separate criticality evaluation in the future. The NCSE under review concludes that the process is safe from criticality events, even in the event that all lithium and boron neutron poisons are lost, provided uranium enrichments are less than 40%. Furthermore, if all the lithium and as much as 98% of the boron would be lost, uranium enrichments of 100% would be allowable. After a thorough review of the NCSE, this reviewer agrees with that conclusion. This technical review consisted of: an independent check of the methods and models employed, independent calculations application of ANSI/ANS 8.1, verification of WSRC Nuclear Criticality Safety Manual({sup 2}) procedures.

A weekly publication, the Texas Register serves as the journal of state agency rulemaking for Texas. Information published in the Texas Register includes proposed, adopted, withdrawn and emergency rule actions, notices of state agency review of agency rules, governor's appointments, attorney general opinions, and miscellaneous documents such as requests for proposals. After adoption, these rulemaking actions are codified into the Texas Administrative Code.

A weekly publication, the Texas Register serves as the journal of state agency rulemaking for Texas. Information published in the Texas Register includes proposed, adopted, withdrawn and emergency rule actions, notices of state agency review of agency rules, governor's appointments, attorney general opinions, and miscellaneous documents such as requests for proposals. After adoption, these rulemaking actions are codified into the Texas Administrative Code.

The principal objective of this research is to gain information on the role that host petroleum-derived oils (1000F+), as well as that of catalytically treated host oils, play when used as liquefaction solvents in coprocessing with coal. The host oil will be extensively characterized and then pretreated in a number of ways which involve catalytic reactions such as hydrogenation, hydrocracking, and isomerization. The pretreated oils will then be characterized by elemental analysis, catalytic dehydrogenation, distillation, GC-MS, and NMR. The effects of the host oil on coprocessing with coal will be compared to those obtained using catalytically modified heavy oils. When appropriate, model compounds will be used to study specific reactions brought about by the pretreatments.

The Computer Incident Advisory Capability (CIAC) operates two information servers for the DOE community, FELICIA (formerly FELIX) and IRBIS. FELICIA is a computer Bulletin Board System (BBS) that can be accessed by telephone with a modem. IRBIS is an anonymous ftp server that can be accessed on the Internet. Both of these servers contain all of the publicly available CIAC, CERT, NIST, and DDN bulletins, virus descriptions, the VIRUS-L moderated virus bulletin board, copies of public domain and shareware virus- detection/protection software, and copies of useful public domain and shareware utility programs. This guide describes how to connect these systems and obtain files from them.

Document issued by the Office of the Attorney General of Texas in Austin, Texas, providing an interpretation of Texas law. It provides the opinion of the Texas Attorney General, Dan Morales, regarding a legal question submitted for clarification: Regarding the number of vacation days to which police officers and fire fighters are entitled in a city with a population of more than 30,000 (RQ-525)

Letter opinion issued by the Office of the Attorney General of Texas in Austin, Texas, providing an interpretation of Texas law. It provides the opinion of the Texas Attorney General, Dan Morales, regarding a legal question submitted for clarification; Whether Bell County is responsible for maintenance of a drainage ditch on private land reflected in a rural subdivision plat, approved by the commissioners court, where the ditch never had been maintained by the county and where flooding from the ditch is not the result of drainage from, or improvements to, a county road (ID# 21823)

The contents of this report present the progress achieved to date on the Heavy Neutral Beam Probe project. This effort is an international collaboration in magnetic confinement fusion energy research sponsored by the US Department of Energy, Office of Energy Research (Confinement Systems Division) and the Centre Canadien de Fusion Magnetique (CCFM). The overall objective of the effort is to develop and apply a neutral particle beam to the study of edge plasma dynamics in discharges on the Tokamak de Varennes (TdeV) facility in Montreal, Canada. To achieve this goal, a research and development project was established to produce the necessary hardware to make such measurements and meet the scheduling requirements of the program. At present the project is in the middle of its second budget period with the instrumentation on-site at TdeV. The first half of this budget period was used to complete total system tests at InterScience, Inc., dismantle and ship the hardware to TdeV, re-assemble and install the HNBP on the tokamak. Integration of the diagnostic into the TdeV facility has progressed to the point of first beam production and measurement on the plasma. At this time, the HNBP system is undergoing final de-bugging prior to re-start …

This paper presents an analysis of the mean time between failures (MTBF) and availability history of the Varian VGT8140, 400 Watt, 140 GHz Gyrotron that was operated on the Microwave Tokamak Experiment (MTX) at the Lawrence Livermore National Laboratory (LLNL).

We have developed a fast, sensitive neutron detector for recording the fusion reaction-rate history of inertial-confinement fusion (ICF) experiments. The detector is based on the fast rise-time of a commercial plastic scintillator (BC-422) and has a response < 25-ps FWHM. A thin piece of scintillator material acts as a neutron-to- light converter. A zoom lens images light from the scintillator surface to a high-speed (15 ps) optical streak camera for recording. The zoom lens allows the scintillator to be positioned between 1 and 50 cm from a target. The camera simulaneously records an optical fiducial pulse which allows the camera time base to be calibrated relative to the incident laser power. Bursts of x rays formed by focusing 20-ps, 2.5-TW laser pulses onto gold disk targets demonstrate the detector resolution to be < 25 ps. We have recorded burn histories for deuterium/tritium-filled targets producing as few as 3 {times} 10{sup 7} neutrons.

The National Storage Laboratory (NSL) at the National Energy Research Supercomputer Center (NERSC) is a prototype facility which is developing data storage and retrieval techniques using hardware that includes a hierarchy of storage devices. The ultimate goal is to store terabytes of data and achieve rapid retrieval times compatible with the type of media where the data is stored. Files stored in the NSL are accessed directly using the Network File System (NFS); in the future, the Andrew File System (AFS) is expected to be used. System level control of files is available using the File Transfer Protocol (FTP) or a set of program-callable routines. We have experimented with storing and retrieving data from fusion experiments at LLNL and at General Atomics in San Diego, California, using computers running UNIX and VMS operating systems. We discuss some issues associated with accessing files whose names are known, but which are not immediately available, the time required for retrieval, and other pertinent parameters.

Document issued by the Office of the Attorney General of Texas in Austin, Texas, providing an interpretation of Texas law. It provides the opinion of the Texas Attorney General, Dan Morales, regarding a legal question submitted for clarification; Whether the County Purchasing Act, section 262.021-.035 of the Local Government Code, applies to purchases made with funds generated by forfeitures under chapter 59 of the Code of Criminal Procedure (RQ-378)

Document issued by the Office of the Attorney General of Texas in Austin, Texas, providing an interpretation of Texas law. It provides the opinion of the Texas Attorney General, Dan Morales, regarding a legal question submitted for clarification; Whether the provisions of article 59.06(c) of the Code of Criminal Procedure, directing that certain forfeited property be deposited in a "special fund in the county treasury," require that such funds be deposited with the county treasurer for placement in the county depository, and related questions (RQ-469)

Document issued by the Office of the Attorney General of Texas in Austin, Texas, providing an interpretation of Texas law. It provides the opinion of the Texas Attorney General, Dan Morales, regarding a legal question submitted for clarification; Whether, under chapter 143 of the Local Government Code, a police officer who has resigned his commission may rescind his resignation and be reinstated, and related questions (RQ-532)

Document issued by the Office of the Attorney General of Texas in Austin, Texas, providing an interpretation of Texas law. It provides the opinion of the Texas Attorney General, Dan Morales, regarding a legal question submitted for clarification; Whether, under certain circumstances, a nonresident scholarship recipient is eligible for resident tuition rates under section 54.064 of the Education Code and related questions (RQ-544)

Document issued by the Office of the Attorney General of Texas in Austin, Texas, providing an interpretation of Texas law. It provides the opinion of the Texas Attorney General, Dan Morales, regarding a legal question submitted for clarification; Questions relating to service of process in justice courts under the Texas Rules of Civil Procedure (RQ-86)