Pulse Combustors - Performance and Control

~nonEmphasising time characterishcs and contIDI, onlyfew workll'v is av'ailable among the numerous reports onPulse combustors. Rare work deals with tWin Pulsecombustorsls] or combined pulse combustor-"dinesystemsl']. Kenffield15] obtained with a combinedconvenhonal Pulse combustor-tulbine system acombushon Pressals gain of 3-7% and a totalPerformance Of the combustor-"dine system for Pulsecombushon 40% higher than that of steady'combushonwhat aught also be due tO the brine characteristics.…     

Characteristics of tar,NOx precursors and their absorption performance with different scrubbing solvents during the pyrolysis of sewage sludge

Recently thermal utilizations of sewage sludge, especially pyrolysis and gasification, are regarded as promising technologies due to efficient utilization of fuel gas. In this study, characteristics of tar and NOx precursors were investigated during the pyrolysis of sewage sludge. Moreover, absorption performance for tar and NOx precursors were also studied by using four kinds of scrubbing mediums: cooking oil, diesel oil, BDF and water. The results showed that nitrogenous light PAHs were the major components of nitrogenous tar produced from the pyrolysis of sewage sludge. As for gravimetric tar and major nitrogenous tar compounds removal, cooking oil was the most suitable absorbent. With respect to NOx precursors, it was concluded that HCN, sharing of about 39.5% of total nitrogen of the sewage sludge, was the main NOx precursor gas whereas NH₃ content could be neglected. Absorption capacity of hydrophobic scrubbing mediums against NOx precursor gases could be arranged as followed: diesel oil > cooking oil > BDF.     

A relational database machine with large semiconductor disk and hardware relational algebra processor

This paper describes the basic concepts, design and implementation decisions, standpoints and significance of the database machine Delta in the scope of Japan’s Fifth Generation Computer Project. Delta is planned to be operational in 1985 for researchers’ use as a backend database machine for logic programming software development. Delta is basically a relational database machine system. It combines hardware facilities for efficient relational database operations, which are typically represented by relational algebra, and software which deals with hardware control and actual database management requirements. Notable features include attribute-based internal schema in accordance with the characteristics found in the relation access from logic programming environment. This is also useful for the hardware relational algebra manipulation algorithm based on merge-sorting of attributes by hardware and a large capacity Semiconductor Disk for fast access to databases. Various implementation decisions of database management requirements are made in this novel system configuration, which will be meaningful to give an example for constructing a hardware and software combination of a relational database machine. Delta is in the stage between detailed design and implementation.     

Effects of 6-anilino-1,3,5-triazine-2,4-dithiol,zinc stearate,and barium stearate on the thermal stabilization of PVC

Individual action and synergistic effect in the combination of 6-anilino-1,3,5-triazine-2,4-dithiol (AF), zinc stearate, and barium stearate on the color stabilization of PVC were investigated. In this system, AF selectively reacts with allylic chlorine atoms in PVC. Consequently, unstable allylic chlorine units were converted to thermally stable allylic structures, thus retarding the development of polyene sequences. Zinc stearate accelerated the reaction of AF with allylic chlorine atoms in PVC, forming the zinc salts of AF (AFZ_nSt, St?C₁–H₃₅COO? ) by reacting with AF. Barium stearate reacted with ZnCl₂ which is formed in the above reaction to give St₂Zn and BaCl₂. Consequently, barium stearate led to the selective reaction of AF with allylic chlorine atoms in PVC and the remarkable retarding effect of discoloration of PVC.     

Simultaneous determination of dissolved organic carbon and phosphorus in waters using flame ionization and photometric detectors

An apparatus with flame ionization and photometric detectors was assembled for the simultaneous determination of dissolved organic carbon (DOC) and phosphorus (DP) in waters. The optimum operating conditions were described. The long-term precision (relative standard deviation) is 5.8% for DOC and 5.2% for DP. The detection limits are 0.09 μg ml⁻¹ for DOC and 0.03 μg ml⁻¹ for DP. The responses for various DOC and DP compounds agreed almost with those obtained by combustion-infrared and persulfate digestion-colorimetric methods, respectively. DOC and DP in several water samples were determined by this method and other methods, and the results obtained by those methods were discussed.     

A scheduling method considering register‐to‐register transfers

In high‐level synthesis, scheduling is an important stage which assigns each operation appearing in a data flow graph to a specific control step, whose results influence the design quality directly. This paper describes a scheduling approach for pipelined datapaths. Since few previous approaches estimate the interconnection cost between register (register‐to‐register cost), our approach introduces a datapath model with interconnection between registers across buses, and minimizes the total hardware cost including the register‐to‐register cost by force‐directed scheduling. © 1999 Scripta Technica, Electr Eng Jpn, 128(3): 63–71, 1999     

Effect on adhesion of new polymerization initiator systems comprising 5‐monosubstituted barbituric acids,aromatic sulfinate amides,and tert‐butyl peroxymaleic acid in dental adhesive resin

To develop a multipurpose dental adhesive resin, the effects of polymerization initiator systems comprising 5‐monosubstituted barbituric acid (5‐MSBA), aromatic sulfinate amide (ASA), and tert‐butyl peroxymaleic acid (t‐BPMA) with 4‐acryloxyethyltrimellitic acid (4‐AET) or its anhydride (4‐AETA) on adhesion and curing time were investigated. Tensile bond strength values of a Ni Cr alloy are affected by the inclusion of t‐BPMA, and the optimum concentration of t‐BPMA in a 5‐MSBA–ASA–t‐BPMA‐type initiator system was found to be 0.5–2.0 wt %, and it was noteworthy that the correlation between the tensile bond strength and curing time on the t‐BPMA‐concentration showed a highly negative correlation of a benzenesulfinate morphoride (BSMo) series adhesive: r = −0.957, and a p‐toluenesulfinate morphoride (p‐TSMo) series adhesive: r = −0.949. The combination of 1‐cyclohexyl‐5‐ethylbarbiturioc acid (CEBA) with ASA provides a high level of tensile bond strength to the Ni Cr alloy, and the optimum concentration of CEBA in a CEBA–ASA–t‐BPMA‐type initiator and the bond strength values were found to be 0.75 wt % CEBA: 52.3 MPa (with BSMo), and 1.0 wt % CEBA: 50.9 MPa (with p‐TSMo), respectively. It was suggested that 5‐MSBA, ASA, and t‐BPMA and their combinations provided the environment where 4‐AETA exhibited good bonding performance with increasing wettability to metal without interference of a charge‐transfer complex derived from a polymerization initiator system such as benzoyl peroxide (BPO)–amine. © 1999 John Wiley & Sons, Inc. J Appl Polym Sci 72: 1655–1668, 1999     

Dehydration of d-glucose in high temperature water at pressures up to 80 MPa

Reaction of d-glucose in water to yield 5-hydroxymethylfurfural (5-HMF), 1,2,4-benzenetriol (BTO) and furfural was studied at high temperatures (up to 400 °C) and high pressures (up to 80 MPa) using a continuous flow reactor. Maximum temperature and pressure conditions gave maximum furfural yield. Increasing pressure from 40 to 70 and 80 MPa enhanced dehydration reactions to 5-HMF, but also enhanced hydrolysis of 5-HMF leading to the production of BTO and thus lead to lower yields of 5-HMF (below 10%). Remarkably, the dehydration reaction to 5-HMF and the hydrolysis of 5-HMF were both enhanced by the increase in water density at 400 °C.     

Polymerization of 2-dibutylamino-1,3,5-triazine-4,6-dithiol on wire during friction process

2-Dibutylamino-1,3,5-triazine-4,6-dithiol (DB) and a mixture of DB and triallylisocyanurate (TAIC) were used as a lubricant during steel wire drawing due to a dry process. DB gave a polymer film with 180 nm in thickness to wire surfaces during the wire drawing. The polymer film had a disulfide structure on the backbone and contained a small amount of DB monomer and olygomer. Molecular weight and polymer weight increased with the drawing rate. The mixture of DB and TAIC gave mainly a three-dimensional polymer film with 225 nm in thickness to wire surfaces during drawing. The polymer film insoluble in THF had mono and disulfide structures and contained a small amount of linear polymer, DB, and TAIC. Such tribological polymerizations are estimated as follows: DB produces dithiyl radicals on a nascent surface formed during drawing and in the presence of oxygen and heat. The dithiyl radicals were polymerized by coupling with each other to give disulfide bonds or added to allyl groups in TAIC to give monosulfide bonds. It is concluded that this technique should be possible to use for unifying metal processing and surface treatment. © 1995 John Wiley & Sons, Inc.     

1-O-alkyl-2,3-diacylglycerols in the skin surface lipids of the hairless mouse

A neutral lipid class was isolated by thin-layer chromatography from the skin surface lipids of the hairless mouse. The fraction migrated faster than triglycerides and had a migration rate similar to that of diacyl alkanediols (diester wax). Upon deacylation, however, the long-chain diols were identified as 1-alkylglycerol ethers based on their chromatographic properties and on the mass spectra of their nicotinylidene derivatives. Thus, the skin lipid fraction was identified as 1-O-alkyl-diacylglycerol. The alkyl moieties were all saturated and even-numbered and ranged in chainlength from C₁₆ to C₂₂ with 1-O-hexadecylglycerol amounting to 34% of the total glycerol ether moieties. The fatty acids derived from this lipid fraction were mostly monoenoic with chainlengths ranging from C₁₆ to C₂₄. The major acyl component was eicosenoic acid (20∶1) representing 61% of the total fatty acids.