20,230 research outputs found
Heat-barrier coatings for combustion chambers
Arc-plasma-sprayed layered coating of graded Inconel and zirconia protects film-coolant ring below injector plate of rocket engine combustion chamber. Interfacial temperature is designed for minimum buildup of stress and to avoid melting of the metal phase in the graded layers
Granular two-phase insulation systems
Easily prepared system, consisting of matrix of hollow zirconia microspheres containing dispersed tungsten powder, produces minimum-cost, prototype test specimen. Combination represents basic concept of highly reflective dispersed phase in low density insulative matrix and is stable at 2200 K. Other combinations of materials are suggested
Intergranular metal phase increases thermal shock resistance of ceramic coating
Dispersed copper phase increases the thermal shock resistance of a plasma-arc-sprayed coating of zirconia used as a heat barrier on a metal substrate. A small amount of copper is deposited on the granules of the zirconia powder before arc-spraying the resultant powder composite onto the substrate
A generalized chemistry version of SPARK
An extension of the reacting H2-air computer code SPARK is presented, which enables the code to be used on any reacting flow problem. Routines are developed calculating in a general fashion, the reaction rates, and chemical Jacobians of any reacting system. In addition, an equilibrium routine is added so that the code will have frozen, finite rate, and equilibrium capabilities. The reaction rate for the species is determined from the law of mass action using Arrhenius expressions for the rate constants. The Jacobian routines are determined by numerically or analytically differentiating the law of mass action for each species. The equilibrium routine is based on a Gibbs free energy minimization routine. The routines are written in FORTRAN 77, with special consideration given to vectorization. Run times for the generalized routines are generally 20 percent slower than reaction specific routines. The numerical efficiency of the generalized analytical Jacobian, however, is nearly 300 percent better than the reaction specific numerical Jacobian used in SPARK
Ceramics for advanced O2/H2 application
Ceramics are prime candidate materials for advanced rocket engines because they possess high-temperature capability, a tolerance for aggressive environments, and low density. A program was conducted to assess the applicability of structural ceramics to advanced versions of the Space Shuttle main engine (SSME). Operating conditions of ceramic turbine components were defined and each component in the hot-gas path was assessed in regard to materials selection, manufacturing process and feasibility, and relative structural reliability. The conclusion is that ceramic components would be viable in advanced SSME turbopumps
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The Volcker Rule: A Legal Analysis
This report provides an introduction to the Volcker Rule, which is the regulatory regime imposed upon banking institutions and their affiliates under Section 619 of the Dodd-Frank Wall Street Reform and Consumer Protection Act of 2010 (P.L. 111-203). The Volker Rule is designed to prohibit âbanking entitiesâ from engaging in all forms of âproprietary tradingâ (i.e., making investments for their own âtrading accountsâ)âactivities that former Federal Reserve Chairman Paul A. Volcker often condemned as contrary to conventional banking practices and a potential risk to financial stability. The statutory language provides only general outlines of prohibited activities and exceptions. Through it, however, Congress has empowered five federal financial regulators with authority to conduct coordinated rulemakings to fill in the details and complete the difficult task of crafting regulations to identify prohibited activities, while continuing to permit activities considered essential to the safety and soundness of banking institutions or to the maintenance of strong capital markets. In December 2014, more than two years after enactment of the law, coordinated implementing regulations were issued by the Office of the Comptroller of the Currency (OCC), the Federal Deposit Insurance Corporation (FDIC), the Board of Governors of the Federal Reserve System (FRB), the Securities and Exchange Commission (SEC), and the Commodity Futures Trading Commission (CFTC).
The Rule is premised on a two-pronged central core restricting activities by âbanking entitiesââa term that includes all FDIC-insured bank and thrift institutions; all bank, thrift, or financial holding companies; all foreign banking operations with certain types of presence in the United States; and all affiliates and subsidiaries of any of these entities. Specifically, the Rule broadly prohibits banking entities from engaging in âproprietary tradingâ and from making investments in or having relationships with hedge and similar âcovered fundsâ that are exempt from registering with the CFTC as commodity pool operators or with the SEC under the Investment Advisors Act. The Rule couples its broad prohibitions with numerous exclusions and by designating myriad activities as permissible so long as various terms and conditions are met, unless they otherwise would involve or result in a material conflict of interest; a material exposure to high-risk assets or high-risk trading strategies; pose a threat to the safety and soundness of the banking entity; or pose a threat to the financial stability of the United States.
The exceptions to the ban on proprietary trading include underwriting by securities underwriters; market-making âdesigned not to exceed the reasonably expected near term demands of clientsâ; trading in government securities; fiduciary activities; insurance company portfolio investments; and risk-mitigating hedging activities. The ban on investing in and owning âcovered fundsâ exempts certain types of funds, under specified conditions, and permits de minimis investment in any such fund up to 3% of the outstanding ownership interests of the fund with an aggregate cap on the total ownership interest in âcovered fundsâ of 3% of the banking entityâs core capital.
To prevent evasion, the Rule has extensive requirements mandating comprehensive compliance programs that include ongoing management involvement, precise metrics measuring risk assessment, verification and documentation of any activities conducted under one of the Ruleâs exceptions or exclusions, and recurring reports and assessments. Full compliance is required by July 21, 2015, subject to the possibility that further extensions may be provided by the regulators. In the case of investments involving âilliquid fundsâ subject to contractual provisions seriously impacting their marketability or sale, full divestiture might not be required until July 21, 2022
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