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This article from Architectural Record discusses the importance of fenestration systems in creating effective barriers for buildings. Building science has advanced to the point where manufacturers offer a range of exterior barrier products that can meet specific performance needs, such as limiting airflow, resisting water, and controlling thermal properties. Fenestration systems, including entrances and movable glass walls, can play a crucial role in meeting these barrier objectives when specified correctly. The choice of which products to use is determined by the architect or designer of a project. The article also provides learning objectives for readers, including recognizing the safety and performance characteristics of fenestration systems and assessing their contributions to green and sustainable design. [Extracted from the article]

In collaboration with Isao Noda, I have been using Raman spectroscopy to study the properties of the bioplastic polyhydroxybutyrate hexanoate (PHBHx), which depend on the percentage of hexanoate (which produces propyl side branches to the polymer chain). The percentages of hexanoate determine the maximum crystallinity that the polymer can experience, and that determines its physical and chemical properties, which include its optical clarity, dyability, flexibility, and thermal properties (melting and glass transition temperature). It is useful to have an easy way to determine the composition; in this column, we describe how Raman spectroscopy was used to show that this is feasible at an accuracy greater than expected. [ABSTRACT FROM AUTHOR]

Metal-organic frameworks (MOFs) are self-assembled combinations of metals and inorganic ligands that result in a relatively young class of highly ordered, porous materials. Because of the number of structural and chemical possibilities, high surface area, controlled pore volume, and favorable thermal properties, MOFs are being investigated in several fields, including chromatography. Because of the enormous interest in a 2018 "Column Watch" article on the subject and the high level of research in the field, this article explores recent (2019-present) activity specifically toward the application of MOFs for liquid chromatography (LC). [ABSTRACT FROM AUTHOR]

Focuses on the design and specification of vinyl product application and installation in the United States. Engineering of reflective vinyl roofing membranes on stress and fire retardation; Assurance of vinyl siding ability on proper sheathing, wall preparation and accessories; Benefits of high thermal energy efficiency.

The article focuses on the ensilication technology which helps the storage and transportation of life-saving vaccines without refrigeration. Topics discussed include lack of public health protection system due to issues of vaccine availability and distribution in under developed countries, disarding of vaccines due to refrigeration failure, and challenges of determining the proper scale and bridging the social and communication gaps between chemists.

The article examines the connection capabilities of the three variable refrigerant flow (VRF) manufacturers and the magnitude of difference in their controls platforms. Topics discussed include the building management system (BMS) and buiilding automation system (BAS), the standard connection of packaged equipment, and the technological innovation on the VRF system.

Raman spectroscopy can be used to determine the temperature of a material when other more direct means are either impractical or not possible. The material's temperature can affect the peak position of Raman bands. When a Raman band shifts significantly with temperature, the monitoring of the peak position can be the most straightforward manner of determining temperature provided the Raman spectrometer has sufficient spectral resolution. Another method is to determine the temperature from the ratio of the Stokes and anti-Stokes signal strengths of a given Raman band. The latter method requires the ability to detect light at wavelengths longer and shorter than that of the laser and an accurate measurement of the wavelength-dependent instrument response function. [ABSTRACT FROM AUTHOR]

The article discusses the review of the U.S. Chemical Safety Board (CSB) report regarding the fire incident at Tesoro refinery in Anacortes, Washington on April 2, 2010. Topics mentioned include the rupture of the heat exchanger shell in the naphtha hydrotreating unit that caused the fire, the highlight on the difficulties of detecting high temperature hydrogen attack (HTHA), and the lack of the understanding on the operation of the commercial hydrotreating unit.

The article reports that heat transfer compound (HTC) is a viscous mastic designed to fill small air gaps between the tracing element and the object to be heated and is effective at transferring heat than static air, but it has relatively poor thermal conductivity compared to the other components in a steam tracing system. It mentions information on high-performance steam tracing technologies were tested which includes fluid tracing system (FTS) and carbon steel tracing (CST).

The article presents a case study wherein a crude vacuum tower overhead system's troubleshoot operation was corrected. The system comprises of 12 steam ejectors and 12 condensers. The vacuum tower pressure became unstable due to the onset of summer and higher cooling water temperature. The importance of offgas analysis, the need to analyze both ejectors and condensers to identify the source of the malfunction, and the impact of motive steam conditions on vacuum column operation are discussed.

The article focuses on the importance of coatings to protect gas turbines from extreme heat. Ramesh Subramanian of Siemens Energy advises power plants to always reduce the thermal conductivity of coating materials. Another challenge facing plants is that different parts of gas turbines require different coating materials that need different application processes. Plants need to ensure that the coating system they select can expand and contract to avoid it from cracking or falling off.

The article discusses the importance of drying hygroscopic resins to prevent possible loss of essential performance properties of polymers. It offers tips on how to determine the dryness of a resin before processing. It also provides information on resins that do not need drying and some polymers that are not susceptible to hydrolysis but may need drying.

The article discusses the emerging 5-layer polyolefin-dedicated (POD) blown film as a technology for non-barrier applications. The technology's specific formulation is intended to provide balanced in-use performance with maximum film extrusion output, outstanding optical properties for high-impact retail display and substantial downgauging potential. It notes that film processors can easily combine high throughput with outstanding film performance with the 5-layer POD coextrusion technology.

The article looks at research funded by the U.S. Department of Homeland Security Assistance to Firefighters Grants program on the safety and effectiveness of compressed air foam systems (CAFS) use compared to water-only systems in structural firefighting. Factors evaluated include fire hose kinking, heat absorption, and gas cooling.

The article reports on reaching the full potential of thermal energy storage. It is said that the cost of large-scale thermal energy storage needs to be reduced for exploiting all the potential. Some new materials are found that might be able to release stored energy at very high temperatures. Thermal energy storage can be much more cost-effective and viable than battery storage of electricity, and a solar thermal power system could reach efficiencies of over 30 percent. The heat produced by solar thermal plants can be applied any place process heat is needed.

The article offers information on the growth in the light emitting diodes (LEDs) industry, highlighting the significance of thermal design. It states that LEDs can provide illumination for hours from solar-cell energy stored in batteries, bringing light to remote areas where electric grids have not reached. It mentions that the phosphor coating performs a light spectrum conversion, absorbing photons at one frequency and emitting at other frequencies.

The article discusses experiments aimed at fusing ceramics with glass while burning in a kiln. Topics reviewed include the the failure of glass to stick to ceramic items while burning and the insertion of lead oxide mixture glaze in order to further evaluate the possible need for change in fusing methodology.

The termal insulation of high temperature equipment may be subjected to many kinds of damages, leading to a degradation of its thermal properties. The aim of the present work was to check and predict damages that may occur during the operation of thermal equipment. This paper describes simulations and experiments that were performed in order to reproduce damages and to predict the degradation of the termal insulation by measuring temperature deviations at the outer wall of the equipment. [ABSTRACT FROM AUTHOR]

The article presents a model illustrating thermal flow in microwave printed-circuit boards (PCBs). It cites the use of a simple microstrip circuit to examine the effects of the plated-through-hole (PTH) for signal-ground connections in the PCB's isolated areas on the heat flow. Also explored are the impacts of the thermal conductivity (TC) on PCB materials with different thermal properties at various power levels.

The article discusses the components of a printed circuit board (PCB) materials. It states that the materials are insulators that provide electrical isolation between transmission lines, components, and semiconductor devices. It mentions that the thermal properties of PCB defines the limit of the power-handling capabilities.

The article discusses the semiconductor devices that operate at high junction temperatures for long period and its impact on the operating performance. It cites that designers should understand the thermal properties of a printed circuit board (PCB) design for a given Monolithic Microwave Integrated Circuit (MMIC) device to minimize thermal resistance and temperature rise. It also discusses the method for computing thermal resistance between a MMIC amplifier and the ambient environment.

The article discusses the new approach to prevent thermal dissipation and power variance in semiconductor processing. It states that advancements of this industry have led to thermal dissipation and power variances which affect manufacturer's production efficiencies and margins. However, these technical hurdles can be prevented by combining thermal management and burn-in operations. Moreover, the details of the new process are also presented.

Discusses requirements to ensure thermal and electromagnetic compatibility (EMC) in manufacturing electronic components and equipment. Background on common EMC problems; Details of simulating electromagnetic interactions by a three-dimensional solution of Maxwell's equations; Recommended strategy for addressing thermal and EMC design.

This article focuses on flashover which is define as the sudden involvement of a room or an area in flames from floor to ceiling caused by thermal radiation feedback. Thermal radiation feedback is the energy of the fire being radiated back to the contents of the room from the walls, floor, and ceiling. This radiation of energy to the contents of the room will raise all the contents to their ignition temperature. Another important concept to understand is the physics of the flashover. Several factors will affect whether or not a room will flash over. The size of the room, the combustible contents, the air supply, and the insulation of the room all combine to determine a room's flashover potential.

Discusses five primary considerations for determining the proper package in microelectronics. Thermal performance; Electrical performance; Physical package attributes; Substrate connectivity; Package assembly considerations.

The article discusses the use of phase diagrams to asses the thermal properties of ceramic materials. A standard phase diagram listing temperature ranges and various proportions of compounds or substances used in ceramic materials is presented. The diagram is divided in various areas with unique physical and chemical properties. An interpretation of graphical lines representing liquid and solid phases of mixtures is presented. A three dimensional version of the diagram is also presented to illustrate phase changes when all oxides in ceramic materials interact.

The article focuses on attaining uniform and balanced flow of material to each cavity in multi-cavity molding. It notes that minor temperature changes from one zone to another can create imbalances in filling within a matter of minutes. It explains the sources of changes in the hot-runner temperature.

The article focuses on the newly developed charger with thermal regulation for lithium-ion (Li-ion) batteries. It notes that this charger has input overvoltage protection (OVP), which alleviates thermal concerns while maximizing the charge rate and it allows only authorized adapters, improving system safely. Moreover, operating details of this newly developed battery charger are discussed.

The article offers information on gold ball bumping, an effective wafer-bumping method. The factors to consider when wafer bumping are coplanarity, conductivity, thermal properties, size and reliability. The process is emerging as a cost-effective, reliable method for many applications, especially as companies change to meet restriction of the use of certain hazardous substances compliance and eliminate lead in their process.

Deals with graphite heating elements in electronics. Applications of the heating equipment; Advantage over ordinary heaters; Benefits from graphite. INSET: The making of a graphite platen heater.

Presents tips in fire extinction of buildings with flat roofs. Options in gaining access to the flat roof; Avoiding danger in roof operations.

The article focuses on the analog sensors developed by instrument companies Analog Devices Inc. and Texas Instruments based on the different of two transistors operated with different densities. It provides the formula and equation of the sensors and discusses their interesting refinement. It also mentions the refinement of the analog and digital sensors to perform and support accurate wide-range temperature sensing.

Reports on the testing of two metallic thermal panels Inconel and titanium during space Mission 77. Panel features; Height and thickness; Plans to use panels as orbiter enhancements.

Reports on the development of a low-cost thermosetting aromatic copolyester that can withstand stress and stability in the air at certain temperatures. Importance of resin in fabricating carbon composite fuselages for supersonic transports; Strengthening of adhesion by interchain transesterfication reaction.

The article discusses factors that should be considered for selection of ceramics and steel bearings. It states the differences between ceramics and metal bearings along with advantages and disadvantages, load resistance, and surface finish. Also mentioned the mechanical and thermal properties of ceramics, the importance of lubrication for steel bearings, and costs of manufacturing steel bearings.

The article discusses the die design procedure where the internal die configuration is molded to deliver polymer from entrance to the exit with the same pressure drop to have a balanced flow. It notes that changing the output can unbalance die flow and lead to a complicated analysis that can be simplified by assuming the process in the die is isothermal. It indicates that a die that cannot be thermally adjusted means the heating is not designed properly or the die is not suited to the polymer.

The article discusses the role of multifunctional thermally conductive compounds in improving the reliability of light-emitting diode (LED). It explains that these compounds can help optimize heat transfer across interfaces in a variety of applications in multiple industries and extend the life span of electronic components.

The article discusses the importance of choosing the right hydraulic fluid, considered as the most relevant component of a hydraulic system. It mentions the ideal characteristics of hydraulic fluid such as having a high thermal stability, long-lasting and with constant viscosity, regardless of temperature. It discusses the factors the influence hydraulic fluid performance including viscosity, water retention and foaming.

The article focuses on the process of metallic plating of WR-10 stainless-steel waveguide. It includes a simple procedure for copper plating stainless-steel WR-10 waveguide sections, up to 40 centimeters in length. It is stated that an anode with a uniform separation from all interior walls of the wave guide allows for efficient plating. It is added that for experiments executed at low temperatures, it is desirable to use a stainless-steel waveguide in the refrigerator for thermal isolation and to plate the waveguide with a higher conductive metallic layer.

The article presents information about HyRelex, a low loss, high reliability, flexible laminates and bonding materials. HyRelex has been introduced by Taconic. The materials provide thermal, mechanical and electrical properties. These also provide superior moisture resistance. HyRelex produces low loss circuit performance because it lessens phase shift with frequency and temperature changes. HyRelex has outstanding properties. It has superb peel strength to aid in high temperature assembly operations and high power handling requirements.

Discusses the use of a finite-element analysis software from Ansys Inc. to evaluate the magnet's steady-state temperature distribution, heat-removal capabilities and cool-down scenarios. Discussion on modeling the magnet's cooling system; What the cooling process calls for; What the software can provide.

The article reports on the move of the U.S. Joint Space Operations Center to track debris after the explosion of weather satellite launched by the Air Force in 1995. The Air Force Space Command officials say that the incident occurred after operators of the National Oceanic and Atmospheric Administration detected a thermal spike in the satellite. According to the Air Force Space Command, a decision was made of rendering the vehicle safe after a spike in temperature found by satellite operators.

The article reports on how power amplifiers have now become feasible with gallium-nitride (GaN) technology because of its thermal behavior.

Reports on the superconductivity of quaternary intermetallic compounds yttrium-nickel boride carbides (Y-Ni-B-C) and yttrium-palladium boride carbide (Y-Pd-B-C). Research conducted by Robert J. Cava and colleagues at the AT&T Bell laboratories and R. Nagarajan of the Tata Institute of Fundamental Research in Bombay, India; Transition temperature of the palladium and nickel compounds; Importance of the compounds; More.

Provides information on the use of TiN (titanium nitride) which can prolong tool life, according to Bohler Edelstahl GmbH, steel company. Information on the use of an upgrade TiCN (Titanium carbon nitrate) for wear problems; Discussion on the economic cost of cuttign tool.

The article reports on the benefits of the method of joining two glass panes to each other and to the door components using the double sided, adhesive-coated, urethane-foam tape made by Norwood Industries Inc. The use of this foam tape will minimize the door's conductive heat losses and seal the joints between the two panes preventing air from leaking. It also function as thermal and moisture barrier. The foam incorporate a special moisture-absorbing additive that reduces condensation on exposed metal and glass surfaces.

Reports on the move of the Electronics Ceramics Division of the Carborundum Co. in starting the process of aluminum nitride, silicon carbide and boron nitride in replacement of beryllia in New York. Risk of developing cancer due to beryllia; Determination of the thermal conductivity properties; Provision of structural support for designs requiring mechanical strength.

The article reports on the development of gallium nitride (GaN) use in GaN-on-diamond devices from Raytheon Co. as replacement for silicon carbide (SiC), and features the devices thermal conductivity

The article discusses the importance of mobile phase pH and elevated temperatures in modern drug discovery. It states that the two important tools are well-suited for Hamilton's PRP-C18 column because the polymer-based stationary phase is chemically inert and has excellent thermal stability above 100 degrees. It adds that these tools allow rapid separation of closely-related basic solutes in their charge-neutral forms that would co-elute under non-alkaline conditions.

The article discusses radiant energy from heat transfer in fires, focusing on the risk of burns or scalds from exposure to radiant energy such as electromagnetic radiation (EMR). First responders have used lightweight protective proximity suits made from vacuum vapor deposition (VVD) aluminized thin film laminates at radiant energy sources. Technological innovations in proximity suits include polymer development, VVD processing, and fabric weaving technologies to improve performance.