Sample records for absorption air conditioner

  1. Air Conditioner/Dehumidifier

    NASA Technical Reports Server (NTRS)

    1986-01-01

    An ordinary air conditioner in a very humid environment must overcool the room air, then reheat it. Mr. Dinh, a former STAC associate, devised a heat pipe based humidifier under a NASA Contract. The system used heat pipes to precool the air; the air conditioner's cooling coil removes heat and humidity, then the heat pipes restore the overcooled air to a comfortable temperature. The heat pipes use no energy, and typical savings are from 15-20%. The Dinh Company also manufactures a "Z" coil, a retrofit cooling coil which may be installed on an existing heater/air conditioner. It will also provide free hot water. The company has also developed a photovoltaic air conditioner and solar powered water pump.

  2. 10 CFR 429.15 - Room air conditioners.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 3 2014-01-01 2014-01-01 false Room air conditioners. 429.15 Section 429.15 Energy... COMMERCIAL AND INDUSTRIAL EQUIPMENT Certification § 429.15 Room air conditioners. (a) Sampling plan for selection of units for testing. (1) The requirements of § 429.11 are applicable to room air conditioners...

  3. 10 CFR 429.15 - Room air conditioners.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 3 2013-01-01 2013-01-01 false Room air conditioners. 429.15 Section 429.15 Energy... COMMERCIAL AND INDUSTRIAL EQUIPMENT Certification § 429.15 Room air conditioners. (a) Sampling plan for selection of units for testing. (1) The requirements of § 429.11 are applicable to room air conditioners...

  4. Development of a solar-powered residential air conditioner

    NASA Technical Reports Server (NTRS)

    1975-01-01

    An extensive review of the literature was conducted which was concerned with the characterization of systems and equipment that could be applicable to the development of solar-powered air conditioners based on the Rankine cycle approach, and the establishment of baseline data defining the performance, physical characteristics, and cost of systems using the LiBr/H2O absorption cycle.

  5. Development of energy saving automatic air conditioner

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Okada, T.; Iijima, T.; Kakinuma, A.

    1986-01-01

    This paper discusses an automatic air conditioner which adopts a new energy saving control method for controlling heat exchange at the heater and the cooler instead of the conventional reheat air-mix one. In this new air conditioner, the cooler does not work when the passenger room is heated and similarly the heater does not work when the passenger room is cooled, minimizing the use rate of the cooler which accounts for the most of the air conditioner's power consumption. Nonetheless, the heat released from the air conditioner to the room can be adjusted smoothly from maximum cooling to maximum heatingmore » just the same as in the conventional type. The results of on-vehicle comparison tests of the above two methods have shown that the energy saving control method saves nearly half of the energy which is consumed in a year with the conventional one, with the room being kept around 25/sup 0/C (77/sup 0/F).« less

  6. Air-conditioner filters enriching dust mites allergen.

    PubMed

    Zhan, Xiaodong; Li, Chaopin; Xu, Haifeng; Xu, Pengfei; Zhu, Haibin; Diao, Jidong; Li, Na; Zhao, Beibei

    2015-01-01

    We detected the concentration of dust mites allergen (Der f1 & Der p1) in the air of different places before and after the starting of air-conditioners in Wuhu City, Anhui, China, and to discuss the relation between the dust mites allergen in air-conditioner filters and the asthma attack. The dust samples were collected from the air-conditioner filters in dining rooms, shopping malls, hotels and households respectively. Concentrations of dust mites major group allergen 1 (Der f 1, Der p1) were detected with enzyme linked immunosorbent assay (ELISA), and the dust mite immune activities were determined by dot-ELISA. The concentration of Der f1 in dining rooms, shopping malls, hotels and households was 1.52 μg/g, 1.24 μg/g, 1.31 μg/g and 1.46 μg/g respectively, and the concentration of Der p1 in above-mentioned places was 1.23 μg/g, 1.12 μg/g, 1.16 μg/g and 1.18 μg/g respectively. The concentration of Der f1 & Der p1 in air was higher after the air-conditioners starting one hours later, and the difference was significant (P<0.05, respectively). Additionally, dot-ELISA findings revealed that the allergen extracted from the dust was capable of reacting with IgE from the sera of asthma mice allergic to dust mites. The study concludes that air-conditioner filters can enrich dust mites major group allergen, and the allergens can induce asthma. The air-conditioner filters shall be cleaned or replaced regularly to prevent or reduce accumulation of the dust mites and its allergens.

  7. Air-conditioner filters enriching dust mites allergen

    PubMed Central

    Zhan, Xiaodong; Li, Chaopin; Xu, Haifeng; Xu, Pengfei; Zhu, Haibin; Diao, Jidong; Li, Na; Zhao, Beibei

    2015-01-01

    We detected the concentration of dust mites allergen (Der f1 & Der p1) in the air of different places before and after the starting of air-conditioners in Wuhu City, Anhui, China, and to discuss the relation between the dust mites allergen in air-conditioner filters and the asthma attack. The dust samples were collected from the air-conditioner filters in dining rooms, shopping malls, hotels and households respectively. Concentrations of dust mites major group allergen 1 (Der f 1, Der p1) were detected with enzyme linked immunosorbent assay (ELISA), and the dust mite immune activities were determined by dot-ELISA. The concentration of Der f1 in dining rooms, shopping malls, hotels and households was 1.52 μg/g, 1.24 μg/g, 1.31 μg/g and 1.46 μg/g respectively, and the concentration of Der p1 in above-mentioned places was 1.23 μg/g, 1.12 μg/g, 1.16 μg/g and 1.18 μg/g respectively. The concentration of Der f1 & Der p1 in air was higher after the air-conditioners starting one hours later, and the difference was significant (P<0.05, respectively). Additionally, dot-ELISA findings revealed that the allergen extracted from the dust was capable of reacting with IgE from the sera of asthma mice allergic to dust mites. The study concludes that air-conditioner filters can enrich dust mites major group allergen, and the allergens can induce asthma. The air-conditioner filters shall be cleaned or replaced regularly to prevent or reduce accumulation of the dust mites and its allergens. PMID:26064381

  8. EVALUATION OF REFRIGERANT FROM MOBILE AIR CONDITIONERS

    EPA Science Inventory

    The report gives results of a project to provide a scientific basis for choosing a reasonable standard of purity for recycled chlorofluorocarbon (CFC) refrigerant in operating automobile air conditioners. The quality of refrigerant from air conditioners in automobiles of differen...

  9. Stirling Air Conditioner for Compact Cooling

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    None

    2010-09-01

    BEETIT Project: Infinia is developing a compact air conditioner that uses an unconventional high efficient Stirling cycle system (vs. conventional vapor compression systems) to produce cool air that is energy efficient and does not rely on polluting refrigerants. The Stirling cycle system is a type of air conditioning system that uses a motor with a piston to remove heat to the outside atmosphere using a gas refrigerant. To date, Stirling systems have been expensive and have not had the right kind of heat exchanger to help cool air efficiently. Infinia is using chip cooling technology from the computer industry tomore » make improvements to the heat exchanger and improve system performance. Infinia’s air conditioner uses helium gas as refrigerant, an environmentally benign gas that does not react with other chemicals and does not burn. Infinia’s improvements to the Stirling cycle system will enable the cost-effective mass production of high-efficiency air conditioners that use no polluting refrigerants.« less

  10. Bacterial community structures in air conditioners installed in Japanese residential buildings.

    PubMed

    Hatayama, Kouta; Oikawa, Yurika; Ito, Hiroyuki

    2018-01-01

    The bacterial community structures in four Japanese split-type air conditioners were analyzed using a next-generation sequencer. A variety of bacteria were detected in the air filter of an air conditioner installed on the first floor. In the evaporator of this air conditioner, bacteria belonging to the genus Methylobacterium, or the family of Sphingomonadaceae, were predominantly detected. On the other hand, the majority of bacteria detected in the air filters and evaporators of air conditioners installed on the fifth and twelfth floors belonged to the family Enterobacteriaceae. The source of bacteria belonging to the family Enterobacteriaceae may have been aerosols generated by toilet flushing in the buildings. Our results suggested the possibility that the bacterial contamination in the air conditioners was affected by the floor level on which they were installed. The air conditioner installed on the lower floor, near the ground, may have been contaminated by a variety of outdoor bacteria, whereas the air conditioners installed on floors more distant from the ground may have been less contaminated by outdoor bacteria. However, these suppositions may apply only to the specific split-type air conditioners that we analyzed, because our sample size was small.

  11. Energy savings potential in air conditioners and chiller systems

    DOE PAGES

    Kaya, Durmus; Alidrisi, Hisham

    2014-01-22

    In the current paper we quantified and evaluated the energy saving potential in air conditioners and chiller systems. Here, we also showed how to reduce the cost of air conditioners and chiller systems in existing facilities on the basis of payback periods. Among the measures investigated were: (1) installing higher efficiency air conditioners, (2) installing higher efficiency chillers, (3) duty cycling air conditioning units, and (4) utilizing existing economizers on air conditioning units. For each method, examples were provided from Arizona, USA. In these examples, the amount of saved energy, the financial evaluation of this energy, and the investment costmore » and pay back periods were calculated.« less

  12. Mold contamination of automobile air conditioner systems.

    PubMed

    Kumar, P; Lopez, M; Fan, W; Cambre, K; Elston, R C

    1990-02-01

    Eight cars belonging to patients who were found to have exacerbation of allergic rhinitis and bronchial asthma after turning on the air conditioner in their cars were examined. Mold concentrations inside the passenger compartment with the a/c turned off and at different climate control settings were lower than concentrations in the outside air. After turning on the air conditioner to "Max", cultures obtained at various intervals revealed that mold concentrations decreased significantly with time. Furthermore, placement of a filter at the portal of entry of outside air significantly reduced the mold concentration in the passenger compartment.

  13. Control Technologies for Room Air-conditioner and Packaged Air-conditioner

    NASA Astrophysics Data System (ADS)

    Ito, Nobuhisa

    Trends of control technologies about air-conditioning machineries, especially room or packaged air conditioners, are presented in this paper. Multiple air conditioning systems for office buildings are mainly described as one application of the refrigeration cycle control technologies including sensors for thermal comfort and heating/ cooling loads are also described as one of the system control technologies. Inverter systems and related technologies for driving variable speed compressors are described in both case of including induction motors and brushless DC motors. Technologies for more accurate control to meet various kind of regulations such as ozone layer destruction, energy saving and global warming, and for eliminating harmonic distortion of power source current, as a typical EMC problem, will be urgently desired.

  14. Ventilating Air-Conditioner

    NASA Technical Reports Server (NTRS)

    Dinh, Khanh

    1994-01-01

    Air-conditioner provides ventilation designed to be used alone or incorporated into cooling or heating system operates efficiently only by recirculating stale air within building. Energy needed to operate overall ventilating cooling or heating system slightly greater than operating nonventilating cooling or heating system. Helps to preserve energy efficiency while satisfying need for increased forced ventilation to prevent accumulation of undesired gases like radon and formaldehyde. Provides fresh treated air to variety of confined spaces: hospital surgeries, laboratories, clean rooms, and printing shops and other places where solvents used. In mobile homes and portable classrooms, eliminates irritant chemicals exuded by carpets, panels, and other materials, ensuring healthy indoor environment for occupants.

  15. 48 CFR 52.223-12 - Refrigeration Equipment and Air Conditioners.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 48 Federal Acquisition Regulations System 2 2013-10-01 2013-10-01 false Refrigeration Equipment... Provisions and Clauses 52.223-12 Refrigeration Equipment and Air Conditioners. As prescribed in 23.804(b), insert the following clause: Refrigeration Equipment and Air Conditioners (MAY 1995) The Contractor shall...

  16. 48 CFR 52.223-12 - Refrigeration Equipment and Air Conditioners.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 48 Federal Acquisition Regulations System 2 2011-10-01 2011-10-01 false Refrigeration Equipment... Provisions and Clauses 52.223-12 Refrigeration Equipment and Air Conditioners. As prescribed in 23.804(b), insert the following clause: Refrigeration Equipment and Air Conditioners (MAY 1995) The Contractor shall...

  17. 48 CFR 52.223-12 - Refrigeration Equipment and Air Conditioners.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 48 Federal Acquisition Regulations System 2 2014-10-01 2014-10-01 false Refrigeration Equipment... Provisions and Clauses 52.223-12 Refrigeration Equipment and Air Conditioners. As prescribed in 23.804(b), insert the following clause: Refrigeration Equipment and Air Conditioners (MAY 1995) The Contractor shall...

  18. 48 CFR 52.223-12 - Refrigeration Equipment and Air Conditioners.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 48 Federal Acquisition Regulations System 2 2010-10-01 2010-10-01 false Refrigeration Equipment... Provisions and Clauses 52.223-12 Refrigeration Equipment and Air Conditioners. As prescribed in 23.804(b), insert the following clause: Refrigeration Equipment and Air Conditioners (MAY 1995) The Contractor shall...

  19. 48 CFR 52.223-12 - Refrigeration Equipment and Air Conditioners.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 48 Federal Acquisition Regulations System 2 2012-10-01 2012-10-01 false Refrigeration Equipment... Provisions and Clauses 52.223-12 Refrigeration Equipment and Air Conditioners. As prescribed in 23.804(b), insert the following clause: Refrigeration Equipment and Air Conditioners (MAY 1995) The Contractor shall...

  20. 77 FR 28519 - Test Procedure Guidance for Room Air Conditioners, Residential Dishwashers, and Residential...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-15

    ... Guidance for Room Air Conditioners, Residential Dishwashers, and Residential Clothes Washers: Public... procedures for room air conditioners, residential dishwashers, and residential clothes washers. DATES: DOE...'s existing test procedures for residential room air conditioners, residential dishwashers, and...

  1. 16 CFR Appendix E to Part 305 - Room Air Conditioners

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 16 Commercial Practices 1 2012-01-01 2012-01-01 false Room Air Conditioners E Appendix E to Part 305 Commercial Practices FEDERAL TRADE COMMISSION REGULATIONS UNDER SPECIFIC ACTS OF CONGRESS RULE... Appendix E to Part 305—Room Air Conditioners Range Information Manufacturer's rated cooling capacity in Btu...

  2. 16 CFR Appendix E to Part 305 - Room Air Conditioners

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 16 Commercial Practices 1 2013-01-01 2013-01-01 false Room Air Conditioners E Appendix E to Part 305 Commercial Practices FEDERAL TRADE COMMISSION REGULATIONS UNDER SPECIFIC ACTS OF CONGRESS RULE... Appendix E to Part 305—Room Air Conditioners Range Information Manufacturer's rated cooling capacity in Btu...

  3. 16 CFR Appendix E to Part 305 - Room Air Conditioners

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 16 Commercial Practices 1 2010-01-01 2010-01-01 false Room Air Conditioners E Appendix E to Part 305 Commercial Practices FEDERAL TRADE COMMISSION REGULATIONS UNDER SPECIFIC ACTS OF CONGRESS RULE... Appendix E to Part 305—Room Air Conditioners Range Information Manufacturer's rated cooling capacity in Btu...

  4. 16 CFR Appendix E to Part 305 - Room Air Conditioners

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 16 Commercial Practices 1 2014-01-01 2014-01-01 false Room Air Conditioners E Appendix E to Part 305 Commercial Practices FEDERAL TRADE COMMISSION REGULATIONS UNDER SPECIFIC ACTS OF CONGRESS ENERGY... LABELING RULEâ) Pt. 305, App. E Appendix E to Part 305—Room Air Conditioners Range Information Manufacturer...

  5. [Gohieria fusca found in dust of air-conditioner filters].

    PubMed

    Qiang, Chai; Xiao-Dong, Zhan; Wei, Guo; Chao-Pin, Li

    2017-09-25

    To investigate the pollution status of Gohieria fusca in the air conditioner-filters of different places in Wuhu City. The dust samples were collected from the filters of air-conditioners in dining rooms, shopping malls, hotels and households between June and September, 2013, and G. fusca was detected in the dust samples. There were 430 dust samples collected and 98 were G. fusca positive with the breeding rate of 22.79%. The difference of breeding rates of G. fusca were statistically significant among the different places ( χ 2 =18.294, P < 0.05). Among 510.5 g dust samples in total, 783 G. fusca mites were detected with an average breeding density of 1.53 mite/g. G. fusca breeds in the dust of air-conditioner filters in Wuhu City gravely.

  6. [Research on dust mite allergen gathered from filters of air-conditioners].

    PubMed

    Zhan, Xiao-dong; Wu, Hua; Hu, Hui-min; Li, Chao-pin

    2015-12-01

    To discuss the relation between the dust mite allergen (Der) in air-conditioner filters and the asthma attack. The dust samples were collected from the filters of air-conditioners in dining rooms, shopping malls, hotels and households, respectively. The concentrations of Der f 1 and Der p1 were detected by ELISA, and the dust mite immune activities were determined by dot-ELISA. The concentrations of Der f 1 in the dining rooms, shopping malls, hotels and households were 1.52, 1.24, 1.31 µg/g and 1.46 µg/g respectively, and the concentrations of Der p 1 were 1.23, 1.12, 1.16 µg/ g and 1.18 µg, respectively. One hour after the running of air-conditioners, the concentrations of Der f 1 and Der p 1 in the air were higher than those before the running of air-conditioners, and the differences were significant (P < 0.05). Additionally, the dot-ELISA results revealed that the allergen extracted from the dust was capable of reacting with IgE from the sera of asthma mice allergic to dust mites. Der f 1 and Der p 1 appear abundantly in the filters of air-conditioners in domestic houses in Wuhu City, and the allergens can induce asthma.

  7. 16 CFR Appendix H to Part 305 - Cooling Performance and Cost for Central Air Conditioners

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... for Central Air Conditioners Manufacturer's rated cooling capacities (Btu's/hr.) Range of SEER's Low High Single Package Units Central Air Conditioners (Cooling Only): All capacities 10.6 16.5 Heat Pumps (Cooling Function): All capacities 10.6 16.0 Split System Units Central Air Conditioners (Cooling Only...

  8. Development of a solar-powered residential air conditioner: System optimization preliminary specification

    NASA Technical Reports Server (NTRS)

    Rousseau, J.; Hwang, K. C.

    1975-01-01

    Investigations aimed at the optimization of a baseline Rankine cycle solar powered air conditioner and the development of a preliminary system specification were conducted. Efforts encompassed the following: (1) investigations of the use of recuperators/regenerators to enhance the performance of the baseline system, (2) development of an off-design computer program for system performance prediction, (3) optimization of the turbocompressor design to cover a broad range of conditions and permit operation at low heat source water temperatures, (4) generation of parametric data describing system performance (COP and capacity), (5) development and evaluation of candidate system augmentation concepts and selection of the optimum approach, (6) generation of auxiliary power requirement data, (7) development of a complete solar collector-thermal storage-air conditioner computer program, (8) evaluation of the baseline Rankine air conditioner over a five day period simulating the NASA solar house operation, and (9) evaluation of the air conditioner as a heat pump.

  9. [Verification of bacteriological safety of PCM 40 air conditioner].

    PubMed

    Dumas, J L; Ducel, G; Rouge, J C

    1991-01-01

    This study assessed the bacteriological safety of the bedside air conditioner PCM 40 (Howorth Airtech), used for prevention of intraoperative hypothermia, by blowing filtered warm air through a special mattress. The 3 microns bacterial filter of the device released 2,968 +/- 5,618 particles of diameter less than 3 microns per m3 of room air, containing 78,798 +/- 37,243 of such particles per m3. The amount of bacteries in the air pulsed from the mattress was 30 +/- 41 cfu/m3 vs 120 cfu/m3 in the ambient air and in the hot air supply tubing it reached 6 +/- 5 cfu/m3 vs 175 +/- 77 cfu/m3. It is concluded that bacteriological data do not contra-indicate the use of this air conditioner in the operating theater. The only limitations for use are the position (prone or lateral position) and type of surgery (neurosurgery).

  10. 77 FR 8178 - Test Procedures for Central Air Conditioners and Heat Pumps: Public Meeting

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-02-14

    ... distribution of those central air conditioning systems and heat pump systems manufactured after January 1, 2010... system central air conditioners and heat pumps be tested using ``the evaporator coil that is likely to... issued two guidance documents surrounding testing central air conditioner and heat pump systems utilizing...

  11. 10 CFR 429.15 - Room air conditioners.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 3 2012-01-01 2012-01-01 false Room air conditioners. 429.15 Section 429.15 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION CERTIFICATION, COMPLIANCE, AND ENFORCEMENT FOR CONSUMER PRODUCTS AND... selected and tested to ensure that— (i) Any represented value of estimated annual operating cost, energy...

  12. Noninvasive evaluation of the chronic influence of local air velocity from an air conditioner using salivary cortisol and skin caspase-14 as biomarkers of psychosomatic and environmental stress.

    PubMed

    Yamaguchi, M; Nishimiya, H

    2012-01-01

    To demonstrate the possibility of evaluating the chronic influence of local air velocity from an air conditioner using noninvasive biomarkers. Over a consecutive 5-day period, 16 healthy young male adults were exposed to air flow from a whole ceiling-type air conditioner (low local air velocity) and from a commercial concentrated exhaust air conditioner (high local air velocity). Salivary cortisol was used as an index of the psychological effects and caspase-14, collected from the stratum corneum, was used as a marker of environmental stress on the skin. Local air velocity generated from the whole ceiling-type air conditioner where the subject's head was positioned was one-seventh that of the exhaust air conditioner. After exposure to the exhaust air conditioner for 5 days, salivary cortisol decreased significantly from morning to evening and skin caspase-14 gradually increased during the day. A significant increase in hydration index from the morning to the evening was found with the whole ceiling-type air conditioner. The effects of chronic exposure to air movement generated by an air conditioner may be quantified by measurement of salivary cortisol and skin caspase-14.

  13. 10 CFR 431.96 - Uniform test method for the measurement of energy efficiency of commercial air conditioners and...

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... efficiency of commercial air conditioners and heat pumps. 431.96 Section 431.96 Energy DEPARTMENT OF ENERGY... Air Conditioners and Heat Pumps Test Procedures § 431.96 Uniform test method for the measurement of energy efficiency of commercial air conditioners and heat pumps. (a) Scope. This section contains test...

  14. 10 CFR 431.96 - Uniform test method for the measurement of energy efficiency of commercial air conditioners and...

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... efficiency of commercial air conditioners and heat pumps. 431.96 Section 431.96 Energy DEPARTMENT OF ENERGY... Air Conditioners and Heat Pumps Test Procedures § 431.96 Uniform test method for the measurement of energy efficiency of commercial air conditioners and heat pumps. (a) Scope. This section contains test...

  15. Understanding Energy Impacts of Oversized Air Conditioners; NREL Highlights, Research & Development, NREL (National Renewable Energy Laboratory)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    None

    2015-06-01

    This NREL highlight describes a simulation-based study that analyzes the energy impacts of oversized residential air conditioners. Researchers found that, if parasitic power losses are minimal, there is very little increase in energy use for oversizing an air conditioner. The research demonstrates that new residential air conditioners can be sized primarily based on comfort considerations, because capacity typically has minimal impact on energy efficiency. The results of this research can be useful for contractors and homeowners when choosing a new air conditioner or heat pump during retrofits of existing homes. If the selected unit has a crankcase heater, performing propermore » load calculations to be sure the new unit is not oversized will help avoid excessive energy use.« less

  16. Assessment of Environmentally Friendly Refrigerants for Window Air Conditioners

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bansal, Pradeep; Shen, Bo

    This paper presents technical assessment of environmentally friendly refrigerants for window air conditioners that currently use refrigerant R410A for residential and commercial applications. The alternative refrigerants that are studied for its replacement include R32, R600a, R290, R1234yf, R1234ze and a mixture of R32 (90% molar concentration) and R125 (10% molar concentration). Baseline experiments were performed on a window unit charged with R410A. The ORNL Heat Pump Design Model was calibrated with the baseline data and was used to assess the comparative performance of the WAC with alternative refrigerants. The paper discusses the advantages and disadvantages of each refrigerants and theirmore » suitability for window air conditioners.« less

  17. Performance test of a grid-tied PV system to power a split air conditioner system in Surabaya

    NASA Astrophysics Data System (ADS)

    Tarigan, E.

    2017-11-01

    Air conditioner for cooling air is one of the major needs for those who live in hot climate area such as Indonesia. This work presents the performance test of a grid-tied PV system to power air conditioner under a hot tropical climate in Surabaya, Indonesia. A 800 WP grid-tied photovoltaic (PV) system was used, and its performance was tested to power a 0.5 pk of split air conditioner system. It was found that about 3.5 kWh daily energy was consumed by the tested air conditioner system, and about 80% it could be supplied from the PV system. While the other 20% was supplied by the grid during periods of low solar irradiation, 440 Wh of energy was fed into the grid during operation out of office hours. By using the grid-tied PV system, the energy production by PV system did not need to match the consumption of the air conditioner. However, a larger capacity of PV system would mean that a higher percentage of the load would be covered by PV system.

  18. 16 CFR Appendix I to Part 305 - Heating Performance and Cost for Central Air Conditioners

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... for Central Air Conditioners Manufacturer's rated heating capacity (Btu's/hr.) Range of HSPF's Low... 16 Commercial Practices 1 2014-01-01 2014-01-01 false Heating Performance and Cost for Central Air Conditioners I Appendix I to Part 305 Commercial Practices FEDERAL TRADE COMMISSION REGULATIONS UNDER SPECIFIC...

  19. Development of a solar-powered residential air conditioner

    NASA Technical Reports Server (NTRS)

    1975-01-01

    The initial objective of the program was the optimization (in terms of cost and performance) of a Rankine cycle mechanical refrigeration system which utilizes thermal energy from a flat solar collector for air conditioning residential buildings. However, feasibility investigations of the adsorption process revealed that a dessicant-type air conditioner offers many significant advantages. As a result, limited efforts were expended toward the optimization of such a system.

  20. [Air-conditioner disease. Results of an industrial medicine survey (author's transl)].

    PubMed

    Molina, C; Aiache, J M; Bedu, M; Menaut, P; Wahl, D; Brestowski, J; Grall, Y

    1982-07-03

    The results of a survey conducted in a company employing 1850 persons working in air-conditioned premises are reported. One hundred and five persons were examined, including 790 who mostly complained of respiratory disorders and 20 controls. Regular check-ups during the last two years have failed to reveal any serious disease. The most frequent complaints were rhinitis and tracheitis, especially among female employees. No alveolitis was observed. The finding of Bacillus subtilis in samples of ambient air and air-conditioner filters in conjunction with the presence of precipitating antibodies against crude extracts from these samples, suggested that the respiratory disorders might have been due to this microorganism. A multifactorial analysis demonstrated a statistically significant correlation between clinical symptoms and immunological disorders. The air-conditioner disease, therefore, may present as a benign condition.

  1. [Fungus microbiota in air conditioners in intensive care units in Teresina, Piauí].

    PubMed

    Mobin, Mitra; do Amparo Salmito, Maria

    2006-01-01

    With the aim of identifying the fungus microbiota in air conditioners in intensive care units (ICUs) within public and private hospitals in Teresina, Piauí, solid material was collected from ten different ICUs. Thirty-three species of Moniliaceae and Dematiaceae were isolated, which was the first report of these in Piauí. High frequencies of Aspergillus niger Van Tieghem (60%), Aspergillus fumigatus Fres (50%), Trichoderma koningii Oudem (50%) and Aspergillus flavus Link: Fr. (40%) were recorded. The air conditioner cleanliness validity had expired in all the ICUs, and the quantity of colony-forming units exceeded the levels permitted by Law 176/00 from the Ministry of Health. It is important to provide individual protection equipment for professionals, adopt hospital infection control measures, raise the awareness of the presence of fungus infection, improve air circulation around the environment, periodically clean the air conditioners, and make health professionals alert to the importance of these fungi in the hospital environment.

  2. Transition to Low-GWP Alternatives in Passenger Vehicle Air Conditioners

    EPA Pesticide Factsheets

    This fact sheet provides current information on low global warming potential (GWP) alternatives in newly manufactured passenger vehicle air conditioners (ACs), in lieu of high-GWP hydrofluorocarbons (HFCs).

  3. 16 CFR Appendix I to Part 305 - Heating Performance and Cost for Central Air Conditioners

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... RULEâ) Pt. 305, App. I Appendix I to Part 305—Heating Performance and Cost for Central Air Conditioners... 16 Commercial Practices 1 2010-01-01 2010-01-01 false Heating Performance and Cost for Central Air Conditioners I Appendix I to Part 305 Commercial Practices FEDERAL TRADE COMMISSION REGULATIONS UNDER SPECIFIC...

  4. 16 CFR Appendix H to Part 305 - Cooling Performance and Cost for Central Air Conditioners

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 16 Commercial Practices 1 2010-01-01 2010-01-01 false Cooling Performance and Cost for Central Air Conditioners H Appendix H to Part 305 Commercial Practices FEDERAL TRADE COMMISSION REGULATIONS UNDER SPECIFIC... RULEâ) Pt. 305, App. H Appendix H to Part 305—Cooling Performance and Cost for Central Air Conditioners...

  5. Development of a solar powered residential air conditioner (General optimization)

    NASA Technical Reports Server (NTRS)

    Lowen, D. J.

    1976-01-01

    A commercially available 3-ton residential Lithium Bromide (LiBr) absorption air conditioner was modified for use with lower temperature solar heated water. The modification included removal of components such as the generator, concentration control chamber, liquid trap, and separator; and the addition of a Chrysler designed generator, an off-the-shelf LiBr-solution pump. The design goal of the modified unit was to operate with water as the heat-transfer fluid at a target temperature of 85 C (185 F), 29.4 C (85 F) cooling water inlet, producing 10.5 kW (3 tons) of cooling. Tests were performed on the system before and after modification to provide comparative data. At elevated temperatures (96 C, 205 F), the test results show that Lithium Bromide was carried into the condenser due to the extremely violent boiling and degraded the evaporator performance.

  6. Influence of environmental characteristics and climatic factors on mites in the dust of air-conditioner filters.

    PubMed

    Wu, J; Liu, Z G; Ran, P X; Wang, B

    2009-12-01

    To investigate mites in the dust of air-conditioner filters (MACF) in China, a total of 652 dust samples were collected from six cities: Guangzhou (n = 129), Nanchang (n = 127), Shanghai (n = 113), Xian (n = 93), Beijing (n = 93), and Shenyang (n = 79). Tarsonemus granarius was the most dominant species (87.2%). Dermatophagoides pteronyssinus and Dermatophagoides farinae only represented 7.0 and 3.0% of total mites, respectively. With latitude increasing, both mite occurrence rate (P < 0.001) and density (mites/g dust) (P < 0.001) were significantly decreasing. Multivariate regression analysis suggested that the annual average temperature and minimum temperature in different cities had dominant influences on MACF density. The logistic regression analysis revealed that the presence of MACF was positively associated with air-conditioner age, utilization time and power. Wall and window type air-conditioner had higher risk of finding MACF than the floor type air-conditioner. As far as the cleaning interval time of ACF was concerned, higher risk ratio and the highest density of MACF were found in the time stage of >3, < or =12 months. It was also suggested that house type could influence the presence of MACF. A negative association between the house floor and the MACF prevalence was found as well. Mites present in the dust of air-conditioner filters are potential indoor threat to asthma and allergy sufferers. In this study, we find that the storage mite Tarsonemus granarius is the predominant species of mites in the dust of air-conditioner filters (MACF). Thus, the possible clinical importance of T. granarius should cause more our attentions in the future. The abundance and distribution of MACF are also found significantly varied in different climatic regions of China. When we try to assess the possible risk of MACF, more attentions should be focused on subtropical region than temperate region. The influence analysis of environmental characteristics on the prevalence of

  7. Swozzle based burner tube premixer including inlet air conditioner for low emissions combustion

    DOEpatents

    Tuthill, Richard Sterling; Bechtel, II, William Theodore; Benoit, Jeffrey Arthur; Black, Stephen Hugh; Bland, Robert James; DeLeonardo, Guy Wayne; Meyer, Stefan Martin; Taura, Joseph Charles; Battaglioli, John Luigi

    2002-01-01

    A burner for use in a combustion system of a heavy-duty industrial gas turbine includes a fuel/air premixer having an air inlet, a fuel inlet, and an annular mixing passage. The fuel/air premixer mixes fuel and air into a uniform mixture for injection into a combustor reaction zone. The burner also includes an inlet flow conditioner disposed at the air inlet of the fuel/air premixer for controlling a radial and circumferential distribution of incoming air. The pattern of perforations in the inlet flow conditioner is designed such that a uniform air flow distribution is produced at the swirler inlet annulus in both the radial and circumference directions. The premixer includes a swozzle assembly having a series of preferably air foil shaped turning vanes that impart swirl to the airflow entering via the inlet flow conditioner. Each air foil contains internal fuel flow passages that introduce natural gas fuel into the air stream via fuel metering holes that pass through the walls of the air foil shaped turning vanes. By injecting fuel in this manner, an aerodynamically clean flow field is maintained throughout the premixer. By injecting fuel via two separate passages, the fuel/air mixture strength distribution can be controlled in the radial direction to obtain optimum radial concentration profiles for control of emissions, lean blow outs, and combustion driven dynamic pressure activity as machine and combustor load are varied.

  8. Statistical analysis of the count and profitability of air conditioners.

    PubMed

    Rady, El Houssainy A; Mohamed, Salah M; Abd Elmegaly, Alaa A

    2018-08-01

    This article presents the statistical analysis of the number and profitability of air conditioners in an Egyptian company. Checking the same distribution for each categorical variable has been made using Kruskal-Wallis test.

  9. 10 CFR 431.92 - Definitions concerning commercial air conditioners and heat pumps.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... measurement. Commercial package air-conditioning and heating equipment means air-cooled, water-cooled... Conditioner means a basic model of commercial package air-conditioning and heating equipment (packaged or split) that is: Used in computer rooms, data processing rooms, or other information technology cooling...

  10. 10 CFR Appendix F to Subpart B of... - Uniform Test Method for Measuring the Energy Consumption of Room Air Conditioners

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... of Room Air Conditioners F Appendix F to Subpart B of Part 430 Energy DEPARTMENT OF ENERGY ENERGY... conditioners at 10 CFR 430.32(b). 1. Definitions. 1.1 “Active mode” means a mode in which the room air... Appliance Manufacturers, titled “Room Air Conditioners,” Standard RAC-1-2008 (incorporated by reference; see...

  11. 10 CFR Appendix F to Subpart B of... - Uniform Test Method for Measuring the Energy Consumption of Room Air Conditioners

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... of Room Air Conditioners F Appendix F to Subpart B of Part 430 Energy DEPARTMENT OF ENERGY ENERGY... conditioners at 10 CFR 430.32(b). 1. Definitions. 1.1“Active mode” means a mode in which the room air... Appliance Manufacturers, titled “Room Air Conditioners,” Standard RAC-1-2008 (incorporated by reference; see...

  12. 10 CFR Appendix F to Subpart B of... - Uniform Test Method for Measuring the Energy Consumption of Room Air Conditioners

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... of Room Air Conditioners F Appendix F to Subpart B of Part 430 Energy DEPARTMENT OF ENERGY ENERGY... conditioners at 10 CFR 430.32(b). 1. Definitions. 1.1“Active mode” means a mode in which the room air... Appliance Manufacturers, titled “Room Air Conditioners,” Standard RAC-1-2008 (incorporated by reference; see...

  13. 10 CFR 431.92 - Definitions concerning commercial air conditioners and heat pumps.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... expressed in identical units of measurement. Commercial package air-conditioning and heating equipment means... application. Computer Room Air Conditioner means a basic model of commercial package air-conditioning and heating equipment (packaged or split) that is: Used in computer rooms, data processing rooms, or other...

  14. Air conditioner operation behaviour based on students' skin temperature in a classroom.

    PubMed

    Song, Gook-Sup; Lim, Jae-Han; Ahn, Tae-Kyung

    2012-01-01

    A total of 25 college students participated in a study to determine when they would use an air conditioner during a lecture in a university classroom. The ambient temperature and relative humidity were measured 75 cm above the floor every minute. Skin temperatures were measured every minute at seven points, according to the recommendation of Hardy and Dubois. The average clothing insulation value (CLO) of subjects was 0.53 ± 0.07 CLO. The mean air velocity in the classroom was 0.13 ± 0.028 m/s. When the subjects turned the air conditioner both on and off, the average ambient temperatures, relative humidity and mean skin temperatures were 27.4 and 23.7 °C (p = 0.000), 40.9 and 40.0% (p = 0.528) and 32.7 and 32.2 °C (p = 0.024), respectively. When the status of the air conditioner was changed, the differences of skin temperatures in core body parts (head, abdomen and thigh) were not statistically significant. However, in the extremities (mid-lower arm, hand, shin and instep), the differences were statistically significant. Subjects preferred a fluctuating environment to a constant temperature condition. We found that a changing environment does not affect classroom study. Copyright © 2011 Elsevier Ltd and The Ergonomics Society. All rights reserved.

  15. Air Sample Conditioner Helps the Waste Treatment Plant Meet Emissions Standards

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Glissmeyer, John A.; Flaherty, Julia E.; Pekour, Mikhail S.

    2014-12-02

    The air in three of the Hanford Site Waste Treatment and Immobilization Plant (WTP) melter off-gas discharge stacks will be hot and humid after passing through the train of emission abatement equipment. The off-gas temperature and humidity levels will be incompatible with the airborne emissions monitoring equipment required for this type of stack. To facilitate sampling from these facilities, an air sample conditioner system will be installed to introduce cool, dry air into the sample stream to reduce the temperature and dew point. This will avoid thermal damage to the instrumentation and problematic condensation. The complete sample transport system mustmore » also deliver at least 50% of the particles in the sample airstream to the sample collection and on-line analysis equipment. The primary components of the sample conditioning system were tested in a laboratory setting. The sample conditioner itself is based on a commercially-available porous tube filter design. It consists of a porous sintered metal tube inside a coaxial metal jacket. The hot gas sample stream passes axially through the porous tube, and the dry, cool air is injected into the jacket and through the porous wall of the inner tube, creating an effective sample diluter. The dilution and sample air mix along the entire length of the porous tube, thereby simultaneously reducing the dew point and temperature of the mixed sample stream. Furthermore, because the dilution air enters through the porous tube wall, the sample stream does not come in contact with the porous wall and particle deposition is reduced in this part of the sampling system. Tests were performed with an environmental chamber to supply air with the temperature and humidity needed to simulate the off-gas conditions. Air from the chamber was passed through the conditioning system to test its ability to reduce the temperature and dew point of the sample stream. To measure particle deposition, oil droplets in the range of 9 to 11

  16. Techno-Economic Analysis of Indian Draft Standard Levels for RoomAir Conditioners

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    McNeil, Michael A.; Iyer, Maithili

    The Indian Bureau of Energy Efficiency (BEE) finalized its first set of efficiency standards and labels for room air conditioners in July of 2006. These regulations followed soon after the publication of levels for frost-free refrigerators in the same year. As in the case of refrigerators, the air conditioner program introduces Minimum Efficiency Performance Standards (MEPS) and comparative labels simultaneously, with levels for one to five stars. Also like the refrigerator program, BEE defined several successive program phases of increasing stringency. In support of BEE's refrigerator program, Lawrence Berkeley National Laboratory (LBNL) produced an analysis of national impacts of standardsmore » in collaboration with the Collaborative Labeling and Standards Program (CLASP). That analysis drew on LBNL's experience with standards programs in the United States, as well as many other countries. Subsequently, as part of the process for setting optimal levels for air conditioner regulations, CLASP commissioned LBNL to provide support to BEE in the form of a techno-economic evaluation of air conditioner efficiency technologies. This report describes the methodology and results of this techno-economic evaluation. The analysis consists of three components: (1) Cost effectiveness to consumers of efficiency technologies relative to current baseline. (2) Impacts on the current market from efficiency regulations. (3) National energy and financial impacts. The analysis relied on detailed and up-to-date technical data made available by BEE and industry representatives. Technical parameters were used in conjunction with knowledge about air conditioner use patterns in the residential and commercial sectors, and prevailing marginal electricity prices, in order to give an estimate of per-unit financial impacts. In addition, the overall impact of the program was evaluated by combining unit savings with market forecasts in order to yield national impacts. LBNL presented preliminary

  17. Product lifetime, energy efficiency and climate change: A case study of air conditioners in Japan.

    PubMed

    Nishijima, Daisuke

    2016-10-01

    This study proposed a modelling technique for estimating life-cycle CO2 emissions of durable goods by considering changes in product lifetime and energy efficiency. The stock and flow of durable goods was modelled by Weibull lifetime distributions and the trend in annual energy efficiency (i.e., annual electricity consumption) of an "average" durable good was formulated as a reverse logistic curve including a technologically critical value (i.e., limit energy efficiency) with respect to time. I found that when the average product lifetime is reduced, there is a trade-off between the reduction in emissions during product use (use phase), due to the additional purchases of new, more energy-efficient air conditioners, and the increase in emissions arising from the additional production of new air conditioners stimulated by the reduction of the average product lifetime. A scenario analysis focused on residential air conditioners in Japan during 1972-2013 showed that for a reduction of average lifetime of 1 year, if the air conditioner energy efficiency limit can be improved by 1.4% from the estimated current efficiency level, then CO2 emissions can be reduced by approximately the same amount as for an extension of average product lifetime of 1 year. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Analysis of Environmentally Friendly Refrigerant Options for Window Air Conditioners

    DOE PAGES

    Bansal, Pradeep; Shen, Bo

    2015-03-12

    This paper presents a technical assessment of environmentally friendly refrigerants as alternatives to R410A for window air conditioners. The alternative refrigerants that are studied for its replacement include R32, a mixture of R32/R125 with 90%/10% molar concentration, R600a, R290, R1234yf, R1234ze and R134a. Baseline experiments were performed on a window unit charged with R410A. The heat pump design model (HPDM) was modified and calibrated with the baseline data and was used to evaluate the comparative performance of the WAC with alternative refrigerants. The paper discusses the advantages and disadvantages of each refrigerants and their suitability for window air conditioners. Amongmore » all the refrigerants studied, R32 offers the best efficiency and the lowest Global Warming Potential (GWP), and hence its use will result in the overall environmental friendliness.« less

  19. [A patient with acute hypersensitivity pneumonitis with a diagnosis of air-conditioner lung, who responded to therapy].

    PubMed

    Ishikawa, Rie; Kamiya, Hiroyuki; Ikushima, Souichiro; Oristu, Masaru; Takemura, Tamiko

    2010-02-01

    The patient was a 48-year-old woman and current smoker. In May 2007, she moved to a new residence. In the middle of the following month, she developed acute respiratory distress and a fever (38 degrees C) after running her air conditioner continuously throughout the night. The chest X-ray film showed diffuse infiltrative shadows in the middle and lower lung fields. After hospital admission, her oxygenation improved without treatment and the infiltrates improved over the clinical course. As a consequence, we suspected hypersensitivity pneumonitis. The bronchoalveolar lavage showed predominant lymphocytes of 72.6%, with a low CD 4/8 ratio of 0.2. Transbronchial lung biopsy findings corresponded to acute hypersensitivity pneumonitis. The results of the environmental challenge test were positive only when her air conditioner was on, resulting, in a diagnosis of air-conditioner lung. Several microorganisms were detected in an environmental sample, but 20 kinds of serum precipitating antibodies were negative on a thorough screening, so no responsible antigen could be identified. The patient's symptoms did not recur after her air conditioner was replaced.

  20. Experimental Determination of Demand Response Control Models and Cost of Control for Ensembles of Window-Mount Air Conditioners

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Geller, Drew Adam; Backhaus, Scott N.

    Control of consumer electrical devices for providing electrical grid services is expanding in both the scope and the diversity of loads that are engaged in control, but there are few experimentally-based models of these devices suitable for control designs and for assessing the cost of control. A laboratory-scale test system is developed to experimentally evaluate the use of a simple window-mount air conditioner for electrical grid regulation services. The experimental test bed is a single, isolated air conditioner embedded in a test system that both emulates the thermodynamics of an air conditioned room and also isolates the air conditioner frommore » the real-world external environmental and human variables that perturb the careful measurements required to capture a model that fully characterizes both the control response functions and the cost of control. The control response functions and cost of control are measured using harmonic perturbation of the temperature set point and a test protocol that further isolates the air conditioner from low frequency environmental variability.« less

  1. Domestic Refrigeration, Freezer, and Window Air Conditioner Service. Teacher Edition.

    ERIC Educational Resources Information Center

    Clemons, Mark

    This curriculum guide contains six units of instruction for a course in domestic refrigerator, freezer, and window air conditioner service. The units cover the following topics: (1) service fundamentals; (2) mechanical components and functions; (3) electrical components and control devices; (4) refrigerator and freezer service; (5) domestic ice…

  2. Huffing air conditioner fluid: a cool way to die?

    PubMed

    Phatak, Darshan R; Walterscheid, Jeffrey

    2012-03-01

    "Huffing," the form of substance abuse involving inhalants, is growing in popularity because of the ease and availability of chemical inhalants in many household products. The purpose in huffing is to achieve euphoria when the chemicals in question interact with the central nervous system in combination with oxygen displacement. The abuser is lulled into a false sense of safety despite the well-documented potential for lethal cardiac arrhythmia and the effects of chronic inhalant abuse, including multisystem organ failure, and brain damage. Huffing air conditioner fluid is a growing problem given the accessibility to outdoor units and their fluid components, such as difluorochloromethane(chlorodifluoromethane, Freon), and we have classified multiple cases of accidental death due to the toxicity of difluorochloromethane. Given the ubiquity of these devices and the vast lack of gating or security devices, they make an inviting target for inhalant abusers. Acute huffing fatalities have distinct findings that are present at the scene, given the position of the decedent and proximity to the air conditioner unit. The purpose of the autopsy in these cases is to exclude other potential causes of death and to procure specimens for toxicological analysis.

  3. Exclusion of particulate allergens by window air conditioners.

    PubMed

    Solomon, W R; Burge, H A; Boise, J R

    1980-04-01

    Effects of window air-conditioner operation on intramural particle levels were assessed in the bedrooms of 20 homes and in 10 outpatient clinic examining rooms during late summer periods. At each site, pollen and spore collections in the mechanically cooled room and a normally ventilated counterpart were compared using volumetric impactors. Substantially lower particle recoveries (median = 16/m3) were found in air-conditioned rooms than in those with open windows alone (median = 253 particles/m3). Furthermore, substantial exclusion of small (e.g., Ganoderma spores) as well as large (ragweed pollens) aerosol components were found by window units. Control studies within normally ventilated rooms and outside their open windows showed a marked but variable inward flux of particles. Window units appear to substantially reduce indoor allergan levels by maintaining the isolation of enclosed spaces from particle-bearing outdoor air.

  4. Development of vehicle magnetic air conditioner (VMAC) technology. Final report

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Gschneidner, Karl A., Jr.; Pecharsky, V.K.; Jiles, David

    2001-08-28

    The objective of Phase I was to explore the feasibility of the development of a new solid state refrigeration technology - magnetic refrigeration - in order to reduce power consumption of a vehicle air conditioner by 30%. The feasibility study was performed at Iowa State University (ISU) together with Astronautics Corporation of America Technology Center (ACATC), Madison, WI, through a subcontract with ISU.

  5. Effects of Air Conditioner Use on Real-World Fuel Economy

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Huff, Shean P; West, Brian H; Thomas, John F

    2013-01-01

    Vehicle data were acquired on-road and on a chassis dynamometer to assess fuel consumption under several steady cruise conditions and at idle. Data were gathered for various air conditioner (A/C) settings and with the A/C off and the windows open. Two vehicles were used in the comparisonstudy: a 2009 Ford Explorer and a 2009 Toyota Corolla. At steady speeds between 64.4 and 112.7 kph (40 and 70 mph), both vehicles consumed more fuel with the A/C on at maximum cooling load (compressor at 100% duty cycle) than when driving with the windows down. The Explorer maintained this trend beyond 112.7more » kph (70 mph), while the Corolla fuel consumption with the windows down matched that of running the A/C at 120.7 kph (75 mph), and exceeded it at 128.7 kph (80 mph). The largest incremental fuel consumption rate penalty due to air conditioner use occurred was nearly constant with a weakslight trend of increasing consumption with increasing compressor (and vehicle) speed. Lower consumption is seenobserved at idle for both vehicles, likely due to the low compressor speed at this operating point« less

  6. Effect of central ventilation and air conditioner system on the concentration and health risk from airborne polycyclic aromatic hydrocarbons.

    PubMed

    Lv, Jinze; Zhu, Lizhong

    2013-03-01

    Central ventilation and air conditioner systems are widely utilized nowadays in public places for air exchange and temperature control, which significantly influences the transfer of pollutants between indoors and outdoors. To study the effect of central ventilation and air conditioner systems on the concentration and health risk from airborne pollutants, a spatial and temporal survey was carried out using polycyclic aromatic hydrocarbons (PAHs) as agent pollutants. During the period when the central ventilation system operated without air conditioning (AC-off period), concentrations of 2-4 ring PAHs in the model supermarket were dominated by outdoor levels, due to the good linearity between indoor air and outdoor air (r(p) > 0.769, p < 0.05), and the slopes (1.2-4.54) indicated that ventilating like the model supermarket increased the potential health risks from low molecular weight PAHs. During the period when the central ventilation and air conditioner systems were working simultaneously (AC-on period), although the total levels of PAHs were increased, the concentrations and percentage of the particulate PAHs indoors declined significantly. The BaP equivalency (BaPeq) concentration indicated that utilization of air conditioning reduced the health risks from PAHs in the model supermarket.

  7. Solar Absorption Refrigeration System for Air-Conditioning of a Classroom Building in Northern India

    NASA Astrophysics Data System (ADS)

    Agrawal, Tanmay; Varun; Kumar, Anoop

    2015-10-01

    Air-conditioning is a basic tool to provide human thermal comfort in a building space. The primary aim of the present work is to design an air-conditioning system based on vapour absorption cycle that utilizes a renewable energy source for its operation. The building under consideration is a classroom of dimensions 18.5 m × 13 m × 4.5 m located in Hamirpur district of Himachal Pradesh in India. For this purpose, cooling load of the building was calculated first by using cooling load temperature difference method to estimate cooling capacity of the air-conditioning system. Coefficient of performance of the refrigeration system was computed for various values of strong and weak solution concentration. In this work, a solar collector is also designed to provide required amount of heat energy by the absorption system. This heat energy is taken from solar energy which makes this system eco-friendly and sustainable. A computer program was written in MATLAB to calculate the design parameters. Results were obtained for various values of solution concentrations throughout the year. Cost analysis has also been carried out to compare absorption refrigeration system with conventional vapour compression cycle based air-conditioners.

  8. Development and Analysis of Desiccant Enhanced Evaporative Air Conditioner Prototype

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kozubal, E.; Woods, J.; Judkoff, R.

    2012-04-01

    This report documents the design of a desiccant enhanced evaporative air conditioner (DEVAP AC) prototype and the testing to prove its performance. Previous numerical modeling and building energy simulations indicate a DEVAP AC can save significant energy compared to a conventional vapor compression AC (Kozubal et al. 2011). The purposes of this research were to build DEVAP prototypes, test them to validate the numerical model, and identify potential commercialization barriers.

  9. Low GWP Refrigerants Modelling Study for a Room Air Conditioner Having Microchannel Heat Exchangers

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Shen, Bo; Bhandari, Mahabir S

    Microchannel heat exchangers (MHX) have found great successes in residential and commercial air conditioning applications, being compact heat exchangers, to reduce refrigerant charge and material cost. This investigation aims to extend the application of MHXs in split, room air conditioners (RAC), per fundamental heat exchanger and system modelling. For this paper, microchannel condenser and evaporator models were developed, using a segment-to-segment modelling approach. The microchannel heat exchanger models were integrated to a system design model. The system model is able to predict the performance indices, such as cooling capacity, efficiency, sensible heat ratio, etc. Using the calibrated system and heatmore » exchanger models, we evaluated numerous low GWP (global warming potential) refrigerants. The predicted system performance indices, e.g. cooling efficiency, compressor discharge temperature, and required compressor displacement volume etc., are compared. Suitable replacements for R22 and R-410A for the room air conditioner application are recommended.« less

  10. Cascade Reverse Osmosis Air Conditioning System: Cascade Reverse Osmosis and the Absorption Osmosis Cycle

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    None

    BEETIT Project: Battelle is developing a new air conditioning system that uses a cascade reverse osmosis (RO)-based absorption cycle. Analyses show that this new cycle can be as much as 60% more efficient than vapor compression, which is used in 90% of air conditioners. Traditional vapor-compression systems use polluting liquids for a cooling effect. Absorption cycles use benign refrigerants such as water, which is absorbed in a salt solution and pumped as liquid—replacing compression of vapor. The refrigerant is subsequently separated from absorbing salt using heat for re-use in the cooling cycle. Battelle is replacing thermal separation of refrigerant withmore » a more efficient reverse osmosis process. Research has shown that the cycle is possible, but further investment will be needed to reduce the number of cascade reverse osmosis stages and therefore cost.« less

  11. Electronics Controls Assessment for the PATRIOT Air Conditioner System. Revision

    DTIC Science & Technology

    1986-04-28

    electronic controls in Army Air Conditioner Systems. This assessment used criteria which included: cost (initial and life cycle), efficiency, weight ...each of the twelve selected controllers as to cost and size Iqualifications was accomplished b) assigning reasonable weight factors according to the...following table:I COST SIZE5 WEIGHT FACTOR (Per Unit Price Range) (Volumetric Range) 1 Under $1000 Under 700 in 3 3 $1000 to $1500 700-1000 in 3 5 $1501

  12. 16 CFR 305.12 - Labeling for central air conditioners, heat pumps, and furnaces.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... pumps, and furnaces. (a) Layout. All energy labels for central air conditioners, heat pumps, and... the end of this part illustrating the basic layout. All positioning, spacing, type sizes, and line... calculated for heating Region IV for the standardized design heating requirement nearest the capacity...

  13. 16 CFR 305.12 - Labeling for central air conditioners, heat pumps, and furnaces.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... pumps, and furnaces. (a) Layout. All energy labels for central air conditioners, heat pumps, and... the end of this part illustrating the basic layout. All positioning, spacing, type sizes, and line... calculated for heating Region IV for the standardized design heating requirement nearest the capacity...

  14. 16 CFR 305.12 - Labeling for central air conditioners, heat pumps, and furnaces.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... pumps, and furnaces. (a) Layout. All energy labels for central air conditioners, heat pumps, and... end of this part illustrating the basic layout. All positioning, spacing, type sizes, and line widths... calculated for heating Region IV for the standardized design heating requirement nearest the capacity...

  15. 16 CFR 305.12 - Labeling for central air conditioners, heat pumps, and furnaces.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... pumps, and furnaces. (a) Layout. All energy labels for central air conditioners, heat pumps, and... the end of this part illustrating the basic layout. All positioning, spacing, type sizes, and line... calculated for heating Region IV for the standardized design heating requirement nearest the capacity...

  16. High efficiency novel window air conditioner

    DOE PAGES

    Bansal, Pradeep

    2015-07-24

    This paper presents the technical development of a high efficiency window air conditioner. In order to achieve higher energy efficiency ratio (EER), the original capacity of the R410A unit was downgraded by replacing the original compressor with a lower capacity but higher EER compressor, while all heat exchangers and the chassis from the original unit were retained. The other subsequent major modifications included – the AC fan motor being replaced with a brushless high efficiency electronically commuted motor (ECM) motor, the capillary tube being replaced with a needle valve to better control the refrigerant flow and refrigerant set points, andmore » R410A being replaced with drop-in environmentally friendly binary mixture of R32 (85% molar concentration)/R125 (15% molar concentration). All these modifications resulted in significant EER enhancement of the modified unit.« less

  17. High efficiency novel window air conditioner

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bansal, Pradeep

    This paper presents the technical development of a high efficiency window air conditioner. In order to achieve higher energy efficiency ratio (EER), the original capacity of the R410A unit was downgraded by replacing the original compressor with a lower capacity but higher EER compressor, while all heat exchangers and the chassis from the original unit were retained. The other subsequent major modifications included – the AC fan motor being replaced with a brushless high efficiency electronically commuted motor (ECM) motor, the capillary tube being replaced with a needle valve to better control the refrigerant flow and refrigerant set points, andmore » R410A being replaced with drop-in environmentally friendly binary mixture of R32 (85% molar concentration)/R125 (15% molar concentration). All these modifications resulted in significant EER enhancement of the modified unit.« less

  18. Acoustic resonance of outer-rotor brushless dc motor for air-conditioner fan

    NASA Astrophysics Data System (ADS)

    Lee, Hong-Joo; Chung, Shi-Uk; Hwang, Sang-Moon

    2008-04-01

    Generation of acoustic noise in electric motor is an interacting combination of mechanical and electromagnetic sources. In this paper, a brushless dc motor for air-conditioner fan is analyzed by finite element method to identify noise source, and the analysis results are verified by experiments, and sensitivity analysis is performed by design of experiments.

  19. Using Field-Metered Data to Quantify Annual Energy Use of Portable Air Conditioners

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Burke, Thomas; Willem, Henry; Ni, Chun Chun

    2014-12-01

    As many regions of the United States experience rising temperatures, consumers have come to rely increasingly on cooling appliances (including portable air conditioners) to provide a comfortable indoor temperature. Home occupants sometimes use a portable air conditioner (PAC) to maintain a desired indoor temperature in a single room or enclosed space. Although PACs in residential use are few compared to centrally installed and room air conditioning (AC) units, the past few years have witnessed an increase of PACs use throughout the United States. There is, however, little information and few research projects focused on the energy consumption and performance ofmore » PACs, particularly studies that collect information from field applications of PACs. The operation and energy consumption of PACs may differ among geographic locations and households, because of variations in cooling load, frequency, duration of use, and other user-selected settings. In addition, the performance of building envelope (thermal mass and air leakage) as well as inter-zonal mixing within the building would substantially influence the ability to control and maintain desirable indoor thermal conditions. Lawrence Berkeley National Laboratory (LBNL) conducted an initial field-metering study aimed at increasing the knowledge and data related to PAC operation and energy consumption in the United States.« less

  20. Cardio-Muscular Conditioner

    NASA Technical Reports Server (NTRS)

    1993-01-01

    In the mid-sixties, Gary Graham, a Boeing designer, developed a cardiovascular conditioner for a planned Air Force orbiting laboratory. After the project was cancelled, Graham participated in space station conditioning studies for the Skylab program. Twenty years later, he used this expertise to develop the Shuttle 2000-1, a physical therapy and athletic development conditioner, available through Contemporary Designs. The machine is used by football teams, sports clinics and medical rehabilitation centers. Cardiovascular fitness and muscular strength development are promoted through both kinetic and plyometric exercises.

  1. Hardware-in-the-Loop Simulation of a Distribution System with Air Conditioners under Model Predictive Control: Preprint

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sparn, Bethany F; Ruth, Mark F; Krishnamurthy, Dheepak

    Many have proposed that responsive load provided by distributed energy resources (DERs) and demand response (DR) are an option to provide flexibility to the grid and especially to distribution feeders. However, because responsive load involves a complex interplay between tariffs and DER and DR technologies, it is challenging to test and evaluate options without negatively impacting customers. This paper describes a hardware-in-the-loop (HIL) simulation system that has been developed to reduce the cost of evaluating the impact of advanced controllers (e.g., model predictive controllers) and technologies (e.g., responsive appliances). The HIL simulation system combines large-scale software simulation with a smallmore » set of representative building equipment hardware. It is used to perform HIL simulation of a distribution feeder and the loads on it under various tariff structures. In the reported HIL simulation, loads include many simulated air conditioners and one physical air conditioner. Independent model predictive controllers manage operations of all air conditioners under a time-of-use tariff. Results from this HIL simulation and a discussion of future development work of the system are presented.« less

  2. Optimum dry-cooling sub-systems for a solar air conditioner

    NASA Technical Reports Server (NTRS)

    Chen, J. L. S.; Namkoong, D.

    1978-01-01

    Dry-cooling sub-systems for residential solar powered Rankine compression air conditioners were economically optimized and compared with the cost of a wet cooling tower. Results in terms of yearly incremental busbar cost due to the use of dry-cooling were presented for Philadelphia and Miami. With input data corresponding to local weather, energy rate and capital costs, condenser surface designs and performance, the computerized optimization program yields design specifications of the sub-system which has the lowest annual incremental cost.

  3. Effect of air-conditioner on fungal contamination

    NASA Astrophysics Data System (ADS)

    Hamada, Nobuo; Fujita, Tadao

    Air-conditioners (AC) produce much dew and wet conditions inside their apparatus, when in operation. We studied the fungal contamination in AC and found that the average fungal contamination of AC filters was about 5-fold greater than that of a carpet, and Cladosporium and Penicillium were predominant in AC filters. The fungal contamination inside AC, which were used everyday, increased more markedly than those not used daily, e.g. a few days per week or rarely. Moreover, the airborne fungal contamination in rooms during air-conditioning was about 2-fold greater than one in rooms without AC, and was highest when air-conditioning started and decreased gradually with time. We recognized that the airborne fungal contamination was controlled by the environmental condition of the rooms, in which AC were used. It is suggested that AC might promote mold allergies in users via airborne fungal spores derived from the AC. On the other hand, AC was estimated to remove moisture in the room atmosphere and carpets, and reduce the relative humidity in rooms. It was found that the average fungal contamination in the house dust of carpets with AC was suppressed by two-third of that in rooms without AC. The use of AC for suppressing fungal hazards was discussed.

  4. Long-term indoor air conditioner filtration and cardiovascular health: A randomized crossover intervention study.

    PubMed

    Chuang, Hsiao-Chi; Ho, Kin-Fai; Lin, Lian-Yu; Chang, Ta-Yuan; Hong, Gui-Bing; Ma, Chi-Ming; Liu, I-Jung; Chuang, Kai-Jen

    2017-09-01

    The association of short-term air pollution filtration with cardiovascular health has been documented. However, the effect of long-term indoor air conditioner filtration on the association between air pollution and cardiovascular health is still unclear. We recruited 200 homemakers from Taipei and randomly assigned 100 of them to air filtration or control intervention; six home visits were conducted per year from 2013 to 2014. The participants under air filtration intervention during 2013 were reassigned to control intervention in 2014. The air pollution measurements consisted of particulate matter less than or equal to 2.5μm in diameter (PM 2.5 ) and total volatile organic compounds (VOCs); blood pressure was monitored for each participant during each visit. The following morning, blood samples were collected after air pollution monitoring. The blood samples were used to analyze biological markers, including high sensitivity-C-reactive protein (hs-CRP), 8-hydroxy-2'-deoxyguanosine (8-OHdG) and fibrinogen. Household information, including cleaning, cooking, and air conditioning, was collected by a questionnaire. Mixed-effects models were used to investigate the associations among air pollution measurements, blood pressure and biological markers. The results showed that increased levels of PM 2.5 and total VOCs were associated with increased hs-CRP, 8-OHdG and blood pressure. The health variables were higher among participants in the control intervention phase than among those in the air filtration intervention phase. We concluded that air pollution exposure was associated with systemic inflammation, oxidative stress and elevated blood pressure. The long-term filtration of air pollution with an air conditioner filter was associated with cardiovascular health of adults. Copyright © 2017 Elsevier Ltd. All rights reserved.

  5. Energy Impacts of Oversized Residential Air Conditioners -- Simulation Study of Retrofit Sequence Impacts

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Booten, C.; Christensen, C.; Winkler, J.

    2014-11-01

    This research addresses the question of what are the energy consequences for oversizing of an air conditioner in a home. Conventional wisdom holds that oversizing the AC results in significant energy penalties. However, the reason for this was shown to be due to crankcase heaters and not due to cycling performance of the AC, and is only valid for a particular set of assumptions. Adding or removing individual characteristics, such as ducts or crankcase heaters, can have measurable impacts on energy use. However, with all other home characteristics held constant, oversizing the AC generally has a small effect on coolingmore » energy use, even if the cycling performance of the unit is poor. The relevant aspects of air conditioner modeling are discussed to illustrate the effects of the cycling loss coefficient, Cd, capacity, climate, ducts and parasitic losses such as crankcase heaters. A case study of a typical 1960's vintage home demonstrates results in the context of whole building simulations using EnergyPlus.« less

  6. Deaths Due to Accidental Air Conditioner Compressor Explosion: A Case Series.

    PubMed

    Behera, Chittaranjan; Bodwal, Jatin; Sikary, Asit K; Chauhan, Mohit Singh; Bijarnia, Manjul

    2017-01-01

    In an air-conditioning system, the compressor is a large electric pump that pressurizes the refrigerant gas as part of the process of turning it back into a liquid. The explosion of an air conditioner (AC) compressor is an uncommon event, and immediate death resulted from the blast effect is not reported in forensic literature. We report three such cases in which young AC mechanics were killed on the spot due to compressor blast, while repairing the domestic split AC unit. The autopsy findings, the circumstances leading to the explosion of the compressor, are discussed in this study. © 2016 American Academy of Forensic Sciences.

  7. Development of a solar-powered residential air conditioner: Economic analysis

    NASA Technical Reports Server (NTRS)

    1975-01-01

    The results of investigations aimed at the development of cost models to be used in the economic assessment of Rankine-powered air conditioning systems for residential application are summarized. The rationale used in the development of the cost model was to: (1) collect cost data on complete systems and on the major equipment used in these systems; (2) reduce these data and establish relationships between cost and other engineering parameters such as weight, size, power level, etc; and (3) derive simple correlations from which cost-to-the-user can be calculated from performance requirements. The equipment considered in the survey included heat exchangers, fans, motors, and turbocompressors. This kind of hardware represents more than 2/3 of the total cost of conventional air conditioners.

  8. ENERGY STAR Certified Non-AHRI Central Air Conditioner Equipment and Air Source Heat Pump

    EPA Pesticide Factsheets

    Certified models meet all ENERGY STAR requirements as listed in the Version 5.0 ENERGY STAR Program Requirements for Air Source Heat Pump and Central Air Conditioner Equipment that are effective as of September 15, 2015. A detailed listing of key efficiency criteria are available at http://www.energystar.gov/index.cfm?c=airsrc_heat.pr_crit_as_heat_pumps Listed products have been submitted to EPA by ENERGY STAR partners that do not participate in the AHRI certification program. EPA will continue to update this list with products that are certified by EPA-recognized certification bodies other than AHRI. The majority of ENERGY STAR products, certified by AHRI, can be found on the CEE/AHRI Verified Directory at http://www.ceedirectory.org/

  9. USAF Bioenvironmental Noise Data Handbook. Volume 167: MA-3M air conditioner

    NASA Astrophysics Data System (ADS)

    Rau, T. H.

    1982-06-01

    The MA-3M is an electric motor-driven air conditioner designed to cool electronic equipment on aircraft during ground maintenance. This report provides measured and extrapolated data defining the bioacoustic environments produced by this unit operating at a normal rated condition. Near-field data are reported for 37 locations in a wide variety of physical and psychoacoustic measures: overall and band sound pressure levels, C-weighted and A-weighted sound levels, preferred speech interference levels, perceived noise levels, and limiting times for total daily exposure of personnel with and without standard Air Force ear protectors.

  10. Progress towards Managing Residential Electricity Demand: Impacts of Standards and Labeling for Refrigerators and Air Conditioners in India

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    McNeil, Michael A.; Iyer, Maithili

    The development of Energy Efficiency Standards and Labeling (EES&L) began in earnest in India in 2001 with the Energy Conservation Act and the establishment of the Indian Bureau of Energy Efficiency (BEE). The first main residential appliance to be targeted was refrigerators, soon to be followed by room air conditioners. Both of these appliances are of critical importance to India's residential electricity demand. About 15percent of Indian households own a refrigerator, and sales total about 4 million per year, but are growing. At the same time, the Indian refrigerator market has seen a strong trend towards larger and more consumptivemore » frost-free units. Room air conditioners in India have traditionally been sold to commercial sector customers, but an increasing number are going to the residential sector. Room air conditioner sales growth in India peaked in the last few years at 20percent per year. In this paper, we perform an engineering-based analysis using data specific to Indian appliances. We evaluate costs and benefits to residential and commercial sector consumers from increased equipment costs and utility bill savings. The analysis finds that, while the BEE scheme presents net benefits to consumers, there remain opportunities for efficiency improvement that would optimize consumer benefits, according to Life Cycle Cost analysis. Due to the large and growing market for refrigerators and air conditioners in India, we forecast large impacts from the standards and labeling program as scheduled. By 2030, this program, if fully implemented would reduce Indian residential electricity consumption by 55 TWh. Overall savings through 2030 totals 385 TWh. Finally, while efficiency levels have been set for several years for refrigerators, labels and MEPS for these products remain voluntary. We therefore consider the negative impact of this delay of implementation to energy and financial savings achievable by 2030.« less

  11. Pulmonary functions in air conditioner users.

    PubMed

    Khaliq, Farah; Sharma, Sameer; Tandon, O P

    2006-01-01

    Air conditioning may affect human health since it has profound effect on our environment, than just lowering temperature. The present study was planned to assess the effect of air conditioners (AC) on pulmonary functions in young healthy non-smoker males. The study group comprised of ten subjects who were using AC's in their cars for at least 1 hr daily since last 6 months. While ten subjects who did not use AC at all served as controls. The pulmonary functions were assessed using PK Morgan 232 spirometer in a closed room. The peak expiratory flow rate (PEFR) and Forced expiratory flow between 25-75% of vital capacity (FEF25-75) were significantly reduced in subjects using car AC's. Inspiratory flow rates also showed a trend towards decline in AC users but could not reach the level of significance. The lung volumes and capacities were not significantly different in the two groups except for forced expiratory volume in 0.5 sec (FEV 0.5 sec), which also decreased in AC users. The airway resistance and lung compliance did not show significant change. In the presence of normal FEV1, reduced FEF25-75% which is the flow rate over the middle half of vital capacity, is an evidence of mild airflow limitation. The result is suggestive of predisposition of AC users towards respiratory disorders in form of mild airflow restriction.

  12. Utilization of air conditioner condenser as water heater in an effort to energy conservation

    NASA Astrophysics Data System (ADS)

    Sonawan, Hery; Saputro, Panji; Kurniawan, Iden Muhtar

    2018-04-01

    This paper presents an experimental study of utilization of air conditioner condenser as water heater. Modification of existing air conditioner system is an effort to harvest waste heat energy from condenser. Modification is conducted in order to test the system into two mode tests, first mode with one condenser and second mode with two condensers. Harvesting the waste heat from condenser needs a theoretical and practice study to see how much the AC performance changes if modifications are made. It should also be considered how the technique of harvesting waste heat for water heating purposes. From the problem, this paper presents a comparison between AC performance before and after modification. From the experiment, an increase in compressor power consumption is 4.3% after adding a new condenser. The hot water temperature is attained to 69 °C and ready for warm bath. The increase in power consumption is not too significant compared to the attainable hot water temperature. Also seen that the value of condenser Performance Factor increase from 5.8 to 6.25 or by 7.8%.

  13. The seasonal performance of a liquid-desiccant air conditioner

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Lowenstein, A.; Novosel, D.

    1995-08-01

    Prior reports on liquid-desiccant systems have focused on their steady-state operation at ARI design conditions. By studying their performance during an entire cooling season, the computer modeling presented here shows that liquid-desiccant systems can have a very high seasonal coefficient of performance (COP). For a liquid-desiccant system that uses a double-effect boiler, COPs ranging from 1.44 in a humid location (Houston) to 2.24 in a dry location (Phoenix) are achieved by fully exploiting indirect evaporative cooling and providing only the minimum latent cooling needed to meet the loads on the building. This minimizes the amount of water absorbed by themore » desiccant and, hence, the amount of thermal energy needed to regenerate it. In applications where latent loads are very high, such as processing the high volumes of ventilation air required to maintain good indoor air quality, the liquid-desiccant air conditioner again has an advantage over vapor-compression equipment. In this study, a liquid-desiccant system is modeled that cools and dehumidifies only the ventilation air of an office building in Atlanta. Although processing an airstream that is only 25% of the total air delivered to the building, the liquid-desiccant system is able to meet 52% of the building`s seasonal cooling requirements and reduce the building`s peak electrical demand by about 47%.« less

  14. Development of a solar-powered residential air conditioner: Screening analysis

    NASA Technical Reports Server (NTRS)

    1975-01-01

    Screening analysis aimed at the definition of an optimum configuration of a Rankine cycle solar-powered air conditioner designed for residential application were conducted. Initial studies revealed that system performance and cost were extremely sensitive to condensing temperature and to the type of condenser used in the system. Consequently, the screening analyses were concerned with the generation of parametric design data for different condenser approaches; i. e., (1) an ambient air condenser, (2) a humidified ambient air condenser (3) an evaporative condenser, and (4) a water condenser (with a cooling tower). All systems feature a high performance turbocompressor and a single refrigerant (R-11) for the power and refrigeration loops. Data were obtained by computerized methods developed to permit system characterization over a broad range of operating and design conditions. The criteria used for comparison of the candidate system approaches were (1) overall system COP (refrigeration effect/solar heat input), (2) auxiliary electric power for fans and pumps, and (3) system installed cost or cost to the user.

  15. Influence of storage methods on the surface roughness of tissue conditioners.

    PubMed

    Hong, Guan; Li, YingAi; Maeda, Takeshi; Mizumachi, Wataru; Sadamori, Shinsuke; Hamada, Taizo; Murata, Hiroshi

    2008-03-01

    The purpose of this study was to compare the influence of three kinds of storage methods on surface roughness of tissue conditioners. Four commercial tissue conditioners (GC Soft Liner, Softone, Fictioner, and Hydro-Cast) were used in this study. Five samples of each material were stored in distilled water, air, and a denture cleanser (Polident). Mean surface roughness (R(a)) values of dental stone casts made from the tissue conditioners were measured after 0, 1, 3, 7, and 14 days of immersion using a profilometer. Significant differences in the R(a) values of the specimens were found among the three storage methods. The values of R(a) significantly increased with increase in immersion time for each storage method, except for the materials stored in air. It was found that the materials stored in air showed the most stable and lowest values of R(a). Results obtained suggested that a tissue conditioner exhibited smooth and minimal change in surface roughness with time when stored in air than in distilled water and denture cleanser.

  16. User-Oriented Modeling Tools for Advanced Hybrid and Climate-Appropriate Rooftop Air Conditioners

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Woolley, Jonathan; Univ. of California, Davis, CA; Modera, Mark

    Hybrid unitary air conditioning systems offer a pathway to substantially reduce energy use and peak electrical demand for cooling, heating, and ventilation in commercial buildings. Hybrid air conditioners incorporate multiple subsystems that are carefully orchestrated to provide climate- and application-specific efficiency advantages. There are a multitude of hybrid system architectures, but common subsystems include: heat recovery ventilation, indirect evaporative cooling, desiccant dehumidification, variable speed fans, modulating dampers, and multi-stage or variable-speed vapor compression cooling. Categorically, hybrid systems can operate in numerous discrete modes. For example: indirect evaporative cooling may operate for periods when the subsystem provides adequate sensible cooling, thenmore » vapor compression cooling will be included when more cooling or dehumidification is necessary. Laboratory assessments, field studies, and simulations have demonstrated that hybrid unitary air conditioners could reduce energy use for cooling and ventilation by 30-90% depending on climate and application. Heretofore, it has been challenging - if not impossible - for practitioners to model hybrid air conditioners as part of building energy simulations; and the limitation has severely obstructed broader adoption of technologies in this class. In this project, we developed a new feature for EnergyPlus that enables modeling hybrid unitary air conditioning equipment for building energy simulations. This is a significant advancement for both theory and practice, and confers public benefit by enabling practitioners to evaluate this compelling efficiency technology as a part of building energy simulations. The feature is a black-box model that requires extensive performance data for each hybrid unitary product. In parallel, we also developed new features for the Technology Performance Exchange to enable manufacturers to submit performance data in a standard format that can be

  17. Technical Road Testing of the 18,000 BTU Air Conditioners (Vibration Profile)

    DTIC Science & Technology

    1990-06-27

    to reco~rd the frequencies and inagnitxies o,~ viand shtck force Jixrts at various specified locations of the air conditioner during the normally...NTIS Cl-,,e.1 # QUIC TAB LE Uojnnooj:icCj L2 Justfifc’to I-, STATEMNT "A" per Nichal Schulterze 8y ___q_ Belvoir Research, Development and Engineering...as4i ___________________________________________ n, nt.,tr ’I. -- [ - I- • 4 ZH N~e o: -- 1.4. - I I U) UP, Le U W3 007J kk. Z3 zm v~d s n C3 .d

  18. Study on the complexity pricing game and coordination of the duopoly air conditioner market with disturbance demand

    NASA Astrophysics Data System (ADS)

    Ma, Junhai; Xie, Lei

    2016-03-01

    The paper focuses on the dynamic pricing game of the duopoly air conditioner market with disturbance in demand and analyzes the influence of disturbance on the dynamic game system. Considering the demand for products, such as air conditioner, varies with different seasons, we assume three cases based on the condition of disturbance, including growth market (Case 1), declining market (Case 2) and completely random market (Case 3). By analyzing these three cases and making comparison among them, the paper shows that the growth market is more sensitive to the changing parameters such as the adjustment variable and the competitive factor than the declining market. It is more difficult to keep the system stable in a growth market. Although the demand is completely random, the dynamic system can reach a stable state, on condition that the adjustment variable is small enough. The results also indicate that the bullwhip effect between the order quantity and the actual demand is weakened gradually along with the price adjustment.

  19. Improving Best Air Conditioner Efficiency by 20-30% through a High Efficiency Fan and Diffuser Stage Coupled with an Evaporative Condenser Pre-Cooler

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Parker, Danny S; Sherwin, John R; Raustad, Richard

    2014-04-10

    The Florida Solar Energy Center (FSEC) conducted a research project to improve the best residential air conditioner condenser technology currently available on the market by retrofitting a commercially-available unit with both a high efficiency fan system and an evaporative pre-cooler. The objective was to integrate these two concepts to achieve an ultra-efficient residential air conditioner design. The project produced a working prototype that was 30% more efficient compared to the best currently-available technologies; the peak the energy efficiency ratio (EER) was improved by 41%. Efficiency at the Air-Conditioning and Refrigeration Institute (ARI) standard B-condition which is used to estimate seasonalmore » energy efficiency ratio (SEER), was raised from a nominal 21 Btu/Wh to 32 Btu/Wh.« less

  20. 10 CFR Appendix F to Subpart B of... - Uniform Test Method for Measuring the Energy Consumption of Room Air Conditioners

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... Engineers (ASHRAE) Standard 16-69, “Method of Testing for Rating Room Air Conditioners.” 2. Test conditions...-1972 and in accordance with ASHRAE Standard 16-69. 4.2Determine the electrical power input (expressed...

  1. 10 CFR Appendix F to Subpart B of... - Uniform Test Method for Measuring the Energy Consumption of Room Air Conditioners

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... Engineers (ASHRAE) Standard 16-69, “Method of Testing for Rating Room Air Conditioners.” 2. Test conditions...-1972 and in accordance with ASHRAE Standard 16-69. 4.2Determine the electrical power input (expressed...

  2. High Efficiency Room Air Conditioner

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bansal, Pradeep

    This project was undertaken as a CRADA project between UT-Battelle and Geberal Electric Company and was funded by Department of Energy to design and develop of a high efficiency room air conditioner. A number of novel elements were investigated to improve the energy efficiency of a state-of-the-art WAC with base capacity of 10,000 BTU/h. One of the major modifications was made by downgrading its capacity from 10,000 BTU/hr to 8,000 BTU/hr by replacing the original compressor with a lower capacity (8,000 BTU/hr) but high efficiency compressor having an EER of 9.7 as compared with 9.3 of the original compressor. However,more » all heat exchangers from the original unit were retained to provide higher EER. The other subsequent major modifications included- (i) the AC fan motor was replaced by a brushless high efficiency ECM motor along with its fan housing, (ii) the capillary tube was replaced with a needle valve to better control the refrigerant flow and refrigerant set points, and (iii) the unit was tested with a drop-in environmentally friendly binary mixture of R32 (90% molar concentration)/R125 (10% molar concentration). The WAC was tested in the environmental chambers at ORNL as per the design rating conditions of AHAM/ASHRAE (Outdoor- 95F and 40%RH, Indoor- 80F, 51.5%RH). All these modifications resulted in enhancing the EER of the WAC by up to 25%.« less

  3. Select Components and Finish System Design of a Window Air Conditioner with Propane

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Shen, Bo; Abdelaziz, Omar

    This report describes the technical targets for developing a high efficiency window air conditioner (WAC) using propane (R-290). The baseline unit selected for this activity is a GE R-410A WAC. We established collaboration with a Chinese rotary compressor manufacturer, to select an R-290 compressor. We first modelled and calibrated the WAC system model using R-410A. Next, we applied the calibrated system model to design the R-290 WAC, and decided the strategies to reduce the system charge below 260 grams and achieve the capacity and efficiency targets.

  4. Flow control of a centrifugal fan in a commercial air conditioner

    NASA Astrophysics Data System (ADS)

    Kim, Jiyu; Bang, Kyeongtae; Choi, Haecheon; Seo, Eung Ryeol; Kang, Yonghun

    2015-11-01

    Air-conditioning fans require a low noise level to provide user comfort and quietness. The aerodynamic noise sources are generated by highly unsteady, turbulent structures near the fan blade. In this study, we investigate the flow characteristics of a centrifugal fan in an air-conditioner indoor unit and suggest control ideas to develop a low noise fan. The experiment is conducted at the operation condition where the Reynolds number is 163000 based on the blade tip velocity and chord length. Intermittent separation occurs at the blade leading edge and thus flow significantly fluctuates there, whereas vortex shedding occurs at the blade trailing edge. Furthermore, the discharge flow observed in the axial plane near the shroud shows low-frequency intermittent behaviors, resulting in high Reynolds stresses. To control these flow structures, we modify the shapes of the blade leading edge and shroud of the centrifugal fan and obtain noise reduction. The flow characteristics of the base and modified fans will be discussed. Supported by 0420-20130051.

  5. A Proposal for the Time Domain Modeling of Split Air Conditioners for Consumer Reimbursement Studies

    NASA Astrophysics Data System (ADS)

    Rezende, Paulo Henrique Oliveira; Almeida Junior, Afonso Bernardino; Gondim, Isaque Nogueira; Oliveira, José Carlos

    2015-04-01

    This paper deals with computer application procedures for the evaluation of the causal consistency between anomalous phenomena manifested in electrical networks, along with the physical damage associated with electrical equipment and possible reimbursement requests. The focus is on the development of an air conditioner appliance model of the type known as split founded upon a representation, in the time domain, in accordance with the Alternative Transients Program (ATP) simulator requirements. This approach permits investigations concerning the performance of the product when submitted to ideal and non-ideal supply conditions. Once the equipment model is implemented in the program, a set of investigative studies are carried out to show the device performance under specific energy quality disturbance conditions. In addition, there are still the results for the validation of the process established through the correlation between computational performance of the air conditioner with corresponding studies carried out experimentally, which are presented herein. Moreover, once the effectiveness of the developed model is verified, it is implemented into the Requests for Reimbursement Software. Investigations related to the correlation between disturbances and the levels of thermal and dielectric tolerance are then performed aiming at illustrating the use of the research results for the reimbursement analyzes purposes.

  6. Solar-powered air-conditioning

    NASA Technical Reports Server (NTRS)

    Clark, D. C.; Rousseau, J.

    1977-01-01

    Report focuses on recent study on development of solar-powered residential air conditioners and is based on selected literature through 1975. Its purposes are to characterize thermal and mechanical systems that might be useful in development of Rankine-cycle approach to solar cooling and assessment of a Lithium Bromide/Water absorption cycle system.

  7. A new ultrasonic temperature measurement system for air conditioners in automobiles

    NASA Astrophysics Data System (ADS)

    Liao, Teh-Lu; Tsai, Wen-Yuan; Huang, Chih-Feng

    2004-02-01

    This paper presents a microcomputer-based ultrasonic temperature sensor system to measure the temperature of an air conditioner (AC) in an automobile. It uses the ultrasonic measurement of the changes in the speed of sound in the air to determine the temperature of the environmental air. The changes in the speed of sound are calculated by combining time-of-flight (TOF) and phase shift techniques. This method can work in a wider range than using phase shift alone and is more accurate than the TOF scheme. In the proposed system, we use 40 ± 2 kHz ultrasonic transducers and adopt a single-pass operation. An 89c51 single-chip microcomputer-based binary frequency shift-keyed (BFSK) signal generator and phase detector are designed to record and calculate the TOF, phase shift of the two frequencies and temperature. These data are then sent to either an LCD display or to a PC for calibration and examination. Experimental results show that the proposed measurement system has a high accuracy of ± 0.4 °C from 0 to 80 °C and can reflect the temperature change within 100 ms.

  8. Performance analysis of the electric vehicle air conditioner by replacing hydrocarbon refrigerant

    NASA Astrophysics Data System (ADS)

    Santoso, Budi; Tjahjana, D. D. D. P.

    2017-01-01

    The thermal comfort in passenger cabins needs an automotive air-conditioning system. The electric vehicle air conditioner system is driven by an electric compressor which includes a compressor and an electric motor. Almost air-conditioning system uses CFC-12, CFC-22 and HFC-134a as refrigerant. However, CFC-12 and CFC-22 will damage the ozone layer. The extreme huge global warming potentials (GWP) values of CFC-12, CFC-22, and HFC-134a represent the serious greenhouse effect of Earth. This article shows new experimental measurements and analysis by using a mixture of HC-134 to replace HFC-134a. The result is a refrigerating effect, the coefficient of performance and energy factor increase along with cooling capacity, both for HFC-134a and HC-134. The refrigerating effect of HC-134 is almost twice higher than HFC-134a. The coefficient of performance value of HC-134 is also 36.42% greater than HFC-134a. Then, the energy factor value of HC-134 is 3.78% greater than HFC-134a.

  9. Increased prevalence of IgG-induced sensitization and hypersensitivity pneumonitis (humidifier lung) in nonsmokers exposed to aerosols of a contaminated air conditioner.

    PubMed

    Baur, X; Richter, G; Pethran, A; Czuppon, A B; Schwaiblmair, M

    1992-01-01

    Specific IgG antibodies against antigens of a contaminated air conditioner were estimated in serum of 134 workers of a printing company. Altogether 64% of the workers investigated revealed significantly elevated levels (> 3 U/ml) of IgG antibodies specific to these antigens as compared to a nonexposed control group. The occurrence of IgG antibodies for microbial extracts were 25% for Fusarium, 23% for Penicillium notatum, 13% for Alternaria tenuis, 12% for Aureobasidium pullulans, 9% for Sphaeropsidales species, 3% for Micropolyspora faeni, 2% for Aspergillus fumigatus and 2% for Thermoactionomyces vulgaris. Out of the 86 workers with elevated IgG antibodies for air conditioner antigens, 59 were nonsmokers. Considering a cut-off level of 10 U/ml IgG for high values, the proportion of smokers to nonsmokers becomes even more pronounced (6 to 36 respectively, binominal test p < 0.001). This is despite the fact that the distribution of smokers and nonsmokers among the 134 workers is approximately equal (60 to 74). All 3 workers with clinical diagnosis of humidifier lung or humidifier fever belonged to the nonsmoker group. Our findings indicate that crude water extracts of contaminated air conditioners are the best choice as antigen source for the diagnosis of humidifier lung in exposed workers. Nonsmokers are shown to have a high risk for immunological sensitization.

  10. Effect of occupant behavior and air-conditioner controls on humidity in typical and high-efficiency homes

    DOE PAGES

    Winkler, Jon; Munk, Jeffrey; Woods, Jason

    2018-04-01

    Increasing insulation levels and improved windows are reducing sensible cooling loads in high-efficiency homes. This trend raises concerns that the resulting shift in the balance of sensible and latent cooling loads may result in higher indoor humidity, occupant discomfort, and stunted adoption of high-efficiency homes. This study utilizes established moisture-buffering and air-conditioner latent degradation models in conjunction with an approach to stochastically model internal gains. Building loads and indoor humidity levels are compared for simulations of typical new construction homes and high-efficiency homes in 10 US cities. The sensitivity of indoor humidity to changes in cooling set point, air-conditioner capacity,more » and blower control parameters are evaluated. The results show that high-efficiency homes in humid climates have cooling loads with a higher fraction of latent loads than the typical new construction home, resulting in higher indoor humidity. Reducing the cooling set point is the easiest method to reduce indoor humidity, but it is not energy efficient, and overcooling may lead to occupant discomfort. Eliminating the blower operation at the end of cooling cycles and reducing the cooling airflow rate also reduce indoor humidity and with a smaller impact on energy use and comfort.« less

  11. Effect of occupant behavior and air-conditioner controls on humidity in typical and high-efficiency homes

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Winkler, Jon; Munk, Jeffrey; Woods, Jason

    Increasing insulation levels and improved windows are reducing sensible cooling loads in high-efficiency homes. This trend raises concerns that the resulting shift in the balance of sensible and latent cooling loads may result in higher indoor humidity, occupant discomfort, and stunted adoption of high-efficiency homes. This study utilizes established moisture-buffering and air-conditioner latent degradation models in conjunction with an approach to stochastically model internal gains. Building loads and indoor humidity levels are compared for simulations of typical new construction homes and high-efficiency homes in 10 US cities. The sensitivity of indoor humidity to changes in cooling set point, air-conditioner capacity,more » and blower control parameters are evaluated. The results show that high-efficiency homes in humid climates have cooling loads with a higher fraction of latent loads than the typical new construction home, resulting in higher indoor humidity. Reducing the cooling set point is the easiest method to reduce indoor humidity, but it is not energy efficient, and overcooling may lead to occupant discomfort. Eliminating the blower operation at the end of cooling cycles and reducing the cooling airflow rate also reduce indoor humidity and with a smaller impact on energy use and comfort.« less

  12. Particulate matter concentrations in residences: an intervention study evaluating stand-alone filters and air conditioners.

    PubMed

    Batterman, S; Du, L; Mentz, G; Mukherjee, B; Parker, E; Godwin, C; Chin, J-Y; O'Toole, A; Robins, T; Rowe, Z; Lewis, T

    2012-06-01

    This study, a randomized controlled trial, evaluated the effectiveness of free-standing air filters and window air conditioners (ACs) in 126 low-income households of children with asthma. Households were randomized into a control group, a group receiving a free-standing HEPA filter placed in the child's sleeping area, and a group receiving the filter and a window-mounted AC. Indoor air quality (IAQ) was monitored for week-long periods over three to four seasons. High concentrations of particulate matter (PM) and carbon dioxide were frequently seen. When IAQ was monitored, filters reduced PM levels in the child's bedroom by an average of 50%. Filter use varied greatly among households and declined over time, for example, during weeks when pollutants were monitored, filter use was initially high, averaging 84±27%, but dropped to 63±33% in subsequent seasons. In months when households were not visited, use averaged only 34±30%. Filter effectiveness did not vary in homes with central or room ACs. The study shows that measurements over multiple seasons are needed to characterize air quality and filter performance. The effectiveness of interventions using free-standing air filters depends on occupant behavior, and strategies to ensure filter use should be an integral part of interventions. Environmental tobacco smoke (ETS) increased particulate matter (PM) levels by about 14 μg/m3 and was often detected using ETS-specific tracers despite restrictions on smoking in the house as reported on questionnaires administered to caregivers. PM concentrations depended on season, filter usage, relative humidity, air exchange ratios, number of children, outdoor PM levels, sweeping/dusting, and presence of a central air conditioner (AC). Free-standing air filters can be an effective intervention that provides substantial reductions in PM concentrations if the filters are used. However, filter use was variable across the study population and declined over the study duration, and

  13. Automotive absorption air conditioner utilizing solar and motor waste heat

    NASA Technical Reports Server (NTRS)

    Popinski, Z. (Inventor)

    1981-01-01

    In combination with the ground vehicles powered by a waste heat generating electric motor, a cooling system including a generator for driving off refrigerant vapor from a strong refrigerant absorbant solution is described. A solar collector, an air-cooled condenser connected with the generator for converting the refrigerant vapor to its liquid state, an air cooled evaporator connected with the condenser for returning the liquid refrigerant to its vapor state, and an absorber is connected to the generator and to the evaporator for dissolving the refrigerant vapor in the weak refrigerant absorbant solution, for providing a strong refrigerant solution. A pump is used to establish a pressurized flow of strong refrigerant absorbant solution from the absorber through the electric motor, and to the collector.

  14. Evaluation of malodor for automobile air conditioner evaporator by using laboratory-scale test cooling bench.

    PubMed

    Kim, Kyung Hwan; Kim, Sun Hwa; Jung, Young Rim; Kim, Man Goo

    2008-09-12

    As one of the measures to improve the environment in an automobile, malodor caused by the automobile air-conditioning system evaporator was evaluated and analyzed using laboratory-scale test cooling bench. The odor was simulated with an evaporator test cooling bench equipped with an airflow controller, air temperature and relative humidity controller. To simulate the same odor characteristics that occur from automobiles, one previously used automobile air conditioner evaporator associated with unpleasant odors was selected. The odor was evaluated by trained panels and collected with aluminum polyester bags. Collected samples were analyzed by thermal desorption into a cryotrap and subsequent gas chromatographic separation, followed by simultaneous olfactometry, flame ionization detector and identified by atomic emission detection and mass spectrometry. Compounds such as alcohols, aldehydes, and organic acids were identified as responsible odor-active compounds. Gas chromatography/flame ionization detection/olfactometry combined sensory method with instrumental analysis was very effective as an odor evaluation method in an automobile air-conditioning system evaporator.

  15. Properties and Cycle Performance of Refrigerant Blends Operating Near and Above the Refrigerant Critical Point, Task 2: Air Conditioner System Study

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Piotr A. Domanski; W. Vance Payne

    2002-10-31

    The main goal of this project was to investigate and compare the performance of an R410A air conditioner to that of an R22 air conditioner, with specific interest in performance at high ambient temperatures at which the condenser of the R410A system may be operating above the refrigerant's critical point. Part 1 of this project consisted of conducting comprehensive measurements of thermophysical for refrigerant R125 and refrigerant blends R410A and R507A and developing new equation of state formulations and mixture models for predicting thermophysical properties of HFC refrigerant blends. Part 2 of this project conducted performance measurements of split-system, 3-tonmore » R22 and R410A residential air conditioners in the 80 to 135 F (27.8 to 57.2 C) outdoor temperature range and development of a system performance model. The performance data was used in preparing a beta version of EVAP-COND, a windows-based simulation package for predicting performance of finned-tube evaporators and condensers. The modeling portion of this project also included the formulation of a model for an air-conditioner equipped with a thermal expansion valve (TXV). Capacity and energy efficiency ratio (EER) were measured and compared. The R22 system's performance was measured over the outdoor ambient temperature range of 80 to 135 F (27.8 to 57.2 C). The same test range was planned for the R410A system. However, the compressor's safety system cut off the compressor at the 135.0 F (57.2 C) test temperature. The highest measurement on this system was at 130.0 F (54.4 C). Subsequently, a custom-manufactured R410A compressor with a disabled safety system and a more powerful motor was installed and performance was measured at outdoor temperatures up to 155.0 F (68.3 C). Both systems had similar capacity and EER performance at 82.0 F (27.8 C). The capacity and EER degradation of both systems were nearly linearly dependent with rising ambient outdoor ambient test temperatures. The performance

  16. Portable Body Temperature Conditioner

    DTIC Science & Technology

    2012-10-01

    TITLE: Portable Body Temperature Conditioner PRINCIPAL INVESTIGATOR...Body Temperature Conditioner 5b. GRANT NUMBER W81XWH-11-1-0792 5c... Conditioner Principal Investigator: Timothy D. Browder, MD Co-Investigator: Deborah Kuhls, MD Co-Investigator: John Fildes, MD Table of Contents

  17. Common faults and their impacts for rooftop air conditioners

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Breuker, M.S.; Braun, J.E.

    This paper identifies important faults and their performance impacts for rooftop air conditioners. The frequencies of occurrence and the relative costs of service for different faults were estimated through analysis of service records. Several of the important and difficult to diagnose refrigeration cycle faults were simulated in the laboratory. Also, the impacts on several performance indices were quantified through transient testing for a range of conditions and fault levels. The transient test results indicated that fault detection and diagnostics could be performed using methods that incorporate steady-state assumptions and models. Furthermore, the fault testing led to a set of genericmore » rules for the impacts of faults on measurements that could be used for fault diagnoses. The average impacts of the faults on cooling capacity and coefficient of performance (COP) were also evaluated. Based upon the results, all of the faults are significant at the levels introduced, and should be detected and diagnosed by an FDD system. The data set obtained during this work was very comprehensive, and was used to design and evaluate the performance of an FDD method that will be reported in a future paper.« less

  18. Efficiency and limitations of the upper airway mucosa as an air conditioner evaluated from the mechanisms of bronchoconstriction in asthmatic subjects.

    PubMed

    Konno, A; Terada, N; Okamoto, Y; Togawa, K

    1985-01-01

    To elucidate a limit to the efficiency of the upper airway mucosa as an air conditioner, the temperatures of the inspiratory air and mucosa were measured in the cervical trachea. Both of them were affected only minimally by change of atmospheric air temperature during resting nose breathing, but were affected greatly by change of mode of breathing. During hyperventilation through the mouth, when the atmospheric air temperature was 1 degree C, a temperature difference of 9 degrees C was noted between inspiratory air in the cervical trachea and body temperature, together with a mucosal temperature fall by 1.86 +/- 0.61 degree C. Wearing of a mask caused a rise of 3 degrees C in the inspiratory air temperature in the cervical trachea.

  19. Draft Genome Sequence of a Novel Chitinophaga sp. Strain, MD30, Isolated from a Biofilm in an Air Conditioner Condensate Pipe

    PubMed Central

    Darris, Maxwell

    2017-01-01

    ABSTRACT Most of the 24 known Chitinophaga species were originally isolated from soils. We report the draft genome sequence of a putatively novel Chitinophaga sp. from a biofilm in an air conditioner condensate pipe. The genome comprises 7,661,303 bp in one scaffold, 5,694 predicted protein-coding sequences, and a G+C content of 47.6%. PMID:29051259

  20. 104. SIGNAL CONDITIONERS FOR BOOSTER INSTRUMENTATION, SOUTHWEST SIDE OF LANDLINE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    104. SIGNAL CONDITIONERS FOR BOOSTER INSTRUMENTATION, SOUTHWEST SIDE OF LANDLINE INSTRUMENTATION ROOM (106), LSB (BLDG. 770) - Vandenberg Air Force Base, Space Launch Complex 3, Launch Pad 3 West, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  1. The use of heteroduplex analysis of polymerase chain reaction products to support the possible transmission of Legionella pneumophila from a malfunctioning automobile air conditioner.

    PubMed

    Pinar, Ahmet; Ramirez, Julio A; Schindler, Laura L; Miller, Richard D; Summersgill, James T

    2002-03-01

    Air conditioner condensates have not been previously associated with cases of Legionnaires' disease. We report the possible transmission of Legionella pneumophila serogroup 1 from a malfunctioning automobile air conditioning system's leaking water onto the floorboard of a car driven for a long distance by the patient. Heteroduplex analysis of polymerase chain reaction products was used to help establish an epidemiologic link between the water specimen and the patient.

  2. Particulate matter concentrations in residences: an intervention study evaluating stand-alone filters and air conditioners

    PubMed Central

    Batterman, S.; Du, L.; Mentz, G.; Mukherjee, B.; Parker, E.; Godwin, C.; Chin, J.-Y.; O'Toole, A.; Robins, T.; Rowe, Z.; Lewis, T.

    2014-01-01

    This study, a randomized controlled trial, evaluated the effectiveness of free-standing air filters and window air conditioners (ACs) in 126 low-income households of children with asthma. Households were randomized into a control group, a group receiving a free-standing HEPA filter placed in the child's sleeping area, and a group receiving the filter and a window-mounted AC. Indoor air quality (IAQ) was monitored for week-long periods over three to four seasons. High concentrations of particulate matter (PM) and carbon dioxide were frequently seen. When IAQ was monitored, filters reduced PM levels in the child's bedroom by an average of 50%. Filter use varied greatly among households and declined over time, for example, during weeks when pollutants were monitored, filter use was initially high, averaging 84 ± 27%, but dropped to 63 ± 33% in subsequent seasons. In months when households were not visited, use averaged only 34 ± 30%. Filter effectiveness did not vary in homes with central or room ACs. The study shows that measurements over multiple seasons are needed to characterize air quality and filter performance. The effectiveness of interventions using free-standing air filters depends on occupant behavior, and strategies to ensure filter use should be an integral part of interventions. PMID:22145709

  3. Alternative Refrigerant Evaluation for High-Ambient-Temperature Environments: R-22 and R-410A Alternatives for Mini-Split Air Conditioners

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Abdelaziz, Omar; Shrestha, Som S.; Munk, Jeffrey D.

    The Oak Ridge National Laboratory (ORNL) High-Ambient-Temperature Evaluation Program for low– global warming potential (Low-GWP) Refrigerants aims to develop an understanding of the performance of low-GWP alternative refrigerants to hydrochlorofluorocarbon (HCFC) and hydrofluorocarbon (HFC) refrigerants in mini-split air conditioners under high-ambient-temperature conditions. This final report describes the parties involved, the alternative refrigerant selection process, the test procedures, and the final results.

  4. Alternative Refrigerant Evaluation for High-Ambient Temperature Environments: R-22 and R-410A Alternatives for Mini-Split Air Conditioners

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Abdelaziz, Omar; Munk, Jeffrey D.; Shrestha, Som S.

    The Oak Ridge National Laboratory (ORNL) High-Ambient Temperature Testing Program for Low-GWP Refrigerants aims to develop an understanding of the performance of low-Global Warming Potential (low-GWP) alternatives to Hydrochlorofluorocarbon (HCFC) and Hydrofluorocarbon (HFC) refrigerants in mini-split air conditioners under high ambient temperature conditions. This interim working paper describes the parties involved, the alternative refrigerants selection process, the test procedures, and the preliminary results.

  5. Micromorphology of pelletized soil conditioners

    NASA Astrophysics Data System (ADS)

    Hirsch, Florian; Dietrich, Nils; Knoop, Christine; Raab, Thomas

    2017-04-01

    Soil conditioners produced by anaerobic digestion and subsequent composting of organic household waste, bear the potential to improve unproductive farmland together with a reduced input risk of unwanted pollutants into the soils. Within the VeNGA project (http://www.biogas-network.de/venga), soil conditioners from anaerobically digested organic household waste are tested for their potential to increase plant growth in glasshouse and field experiments. Because the production techniques of these soil conditioners may influence their physical and chemical behaviour in the soil, two different techniques for pelletizing the soil conditioners where applied. We present findings from a pot experiment with cereal that has been sampled after two months for micromorphological analyses. We visualize the decomposition and the physical behaviour of the soil conditioners. Pellets produced in an agglomeration mixer result in dense balls, that are only slightly decomposed after the trial. But the soil conditioners created under pressure in a screw extruder are rich in voids and have the potential of retaining more soil water.

  6. Draft Genome Sequence of a Novel Chitinophaga sp. Strain, MD30, Isolated from a Biofilm in an Air Conditioner Condensate Pipe.

    PubMed

    Wan, Xuehua; Darris, Maxwell; Hou, Shaobin; Donachie, Stuart P

    2017-10-19

    Most of the 24 known Chitinophaga species were originally isolated from soils. We report the draft genome sequence of a putatively novel Chitinophaga sp. from a biofilm in an air conditioner condensate pipe. The genome comprises 7,661,303 bp in one scaffold, 5,694 predicted protein-coding sequences, and a G+C content of 47.6%. Copyright © 2017 Wan et al.

  7. Use of metal conditioner on reinforcement wires to improve denture repair strengths.

    PubMed

    Shimizu, Hiroshi; Mori, Nobuaki; Takahashi, Yutaka

    2008-03-01

    The purpose of this study was to evaluate the transverse strength of denture base resin repaired with autopolymerizing resin and metal wire using a metal conditioner, along with the synergistic effect of a surface preparation for denture base resin. It was found that the use of Co-Cr-Ni wires air abraded with 50 microm alumina, followed by treatment with a metal conditioner and dichloromethane for denture base resin, was the most effective method for repairing fractured denture base resin.

  8. Effect of heat recovery water heater system on the performance of residential split air conditioner using hydrocarbon refrigerant (HCR22)

    NASA Astrophysics Data System (ADS)

    Aziz, A.; Thalal; Amri, I.; Herisiswanto; Mainil, A. K.

    2017-09-01

    This This paper presents the performance of residential split air conditioner (RSAC) using hydrocarbon refrigerant (HCR22) as the effect on the use of heat recovery water heater system (HRWHS). In this study, RSAC was modified with addition of dummy condenser (trombone coil type) as heat recovery water heater system (HRWHS). This HRWHS is installed between a compressor and a condenser by absorbing a part of condenser waste heat. The results show that RSAC with HRWHS is adequate to generate hot water with the temperature range about 46.58˚C - 48.81˚C when compared to without HRWHS and the use of dummy condenser does not give significant effect to the split air conditioner performance. When the use of HRWHS, the refrigerant charge has increase about 19.05%, the compressor power consumption has slightly increase about 1.42% where cooling capacity almost the same with slightly different about 0.39%. The condenser heat rejection is lower about 2.68% and the COP has slightly increased about 1.05% when compared to without HRWHS. The use of HRWHS provide free hot water, it means there is energy saving for heating water without negative impact to the system performance of RSAC.

  9. Solar-Powered, Liquid-Desiccant Air Conditioner for Low-Electricity Humidity Control

    DTIC Science & Technology

    2012-11-01

    reading Current transformer Regen and conditioner Continental Controls CTS-0750-30 1 % of reading Pyranometer Horizontal Campbell...indoor comfort conditions. A pyranometer was used to quantify the efficiency of the solar collector array. Two measurements of electric energy were

  10. Measurement of Fine Particles From Mobile and Stationary Sources, and Reducing the Air Conditioner Power Consumption in Hybrid Electric Vehicles

    NASA Astrophysics Data System (ADS)

    Brewer, Eli Henry

    We study the PM2.5and ultrafine exhaust emissions from a new natural gas-fired turbine power facility to better understand air pollution in California. To characterize the emissions from new natural gas turbines, a series of tests were performed on a GE LMS100 gas turbine. These tests included PM2.5 and wet chemical tests for SO2/SO 3 and NH3, as well as ultrafine (less than 100 nm in diameter) particulate matter measurements. The turbine exhaust had an average particle number concentration that was 2.3x103 times higher than ambient air. The majority of these particles were nanoparticles; at the 100 nm size, stack particle concentrations were about 20 times higher than ambient, and increased to 3.9x104 times higher on average in the 2.5 - 3 nm particle size range. This study also found that ammonia emissions were higher than expected, but in compliance with permit conditions. This was possibly due to an ammonia imbalance entering the catalyst, some flue gas bypassing the catalyst, or not enough catalyst volume. SO3 accounted for an average of 23% of the total sulfur oxides emissions measured. Some of the SO3 is formed in the combustion process, it is likely that the majority formed as the SO2 in the combustion products passed across the oxidizing CO catalyst and SCR catalyst. The 100 MW turbine sampled in this study emitted particle loadings similar to those previously measured from turbines in the SCAQMD area, however, the turbine exhaust contained far more particles than ambient air. The power consumed by an air conditioner accounts for a significant fraction of the total power used by hybrid and electric vehicles especially during summer. This study examined the effect of recirculation of cabin air on power consumption of mobile air conditioners both in-lab and on-road. Real time power consumption and vehicle mileage were recorded by an On Board Diagnostic monitor and carbon balance method. Vehicle mileage improved with increased cabin air recirculation. The

  11. 10 CFR Appendix M to Subpart B of... - Uniform Test Method for Measuring the Energy Consumption of Central Air Conditioners and Heat Pumps

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 3 2012-01-01 2012-01-01 false Uniform Test Method for Measuring the Energy Consumption of Central Air Conditioners and Heat Pumps M Appendix M to Subpart B of Part 430 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY CONSERVATION PROGRAM FOR CONSUMER PRODUCTS Test Procedures Pt. 430, Subpt. B, App. M Appendix M to Subpart B of...

  12. 10 CFR Appendix M to Subpart B of... - Uniform Test Method for Measuring the Energy Consumption of Central Air Conditioners and Heat Pumps

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 3 2013-01-01 2013-01-01 false Uniform Test Method for Measuring the Energy Consumption of Central Air Conditioners and Heat Pumps M Appendix M to Subpart B of Part 430 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY CONSERVATION PROGRAM FOR CONSUMER PRODUCTS Test Procedures Pt. 430, Subpt. B, App. M Appendix M to Subpart B of...

  13. 10 CFR Appendix M to Subpart B of... - Uniform Test Method for Measuring the Energy Consumption of Central Air Conditioners and Heat Pumps

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 3 2014-01-01 2014-01-01 false Uniform Test Method for Measuring the Energy Consumption of Central Air Conditioners and Heat Pumps M Appendix M to Subpart B of Part 430 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY CONSERVATION PROGRAM FOR CONSUMER PRODUCTS Test Procedures Pt. 430, Subpt. B, App. M Appendix M to Subpart B of...

  14. 10 CFR Appendix M to Subpart B of... - Uniform Test Method for Measuring the Energy Consumption of Central Air Conditioners and Heat Pumps

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 3 2010-01-01 2010-01-01 false Uniform Test Method for Measuring the Energy Consumption of Central Air Conditioners and Heat Pumps M Appendix M to Subpart B of Part 430 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY CONSERVATION PROGRAM FOR CONSUMER PRODUCTS Test Procedures Pt. 430, Subpt. B, App. M Appendix M to Subpart B of...

  15. 10 CFR Appendix M to Subpart B of... - Uniform Test Method for Measuring the Energy Consumption of Central Air Conditioners and Heat Pumps

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 3 2011-01-01 2011-01-01 false Uniform Test Method for Measuring the Energy Consumption of Central Air Conditioners and Heat Pumps M Appendix M to Subpart B of Part 430 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION ENERGY CONSERVATION PROGRAM FOR CONSUMER PRODUCTS Test Procedures Pt. 430, Subpt. B, App. M Appendix M to Subpart B of...

  16. Split-flow regeneration in absorptive air separation

    DOEpatents

    Weimer, Robert F.

    1987-01-01

    A chemical absorptive separation of air in multiple stage of absorption and desorption is performed with partial recycle of absorbent between stages of desorption necessary to match equilibrium conditions in the various stages of absorption. This allows reduced absorbent flow, reduced energy demand and reduced capital costs.

  17. Greenhouse gas emissions for refrigerant choices in room air conditioner units.

    PubMed

    Galka, Michael D; Lownsbury, James M; Blowers, Paul

    2012-12-04

    In this work, potential replacement refrigerants for window-mounted room air conditioners (RACs) in the U.S. have been evaluated using a greenhouse gas (GHG) emissions analysis. CO(2)-equivalent emissions for several hydrofluoroethers (HFEs) and other potential replacements were compared to the most widely used refrigerants today. Included in this comparison are pure refrigerants that make up a number of hydrofluorocarbon (HFC) mixtures, pure hydrocarbons, and historically used refrigerants such as propane and ammonia. GHG emissions from direct and indirect sources were considered in this thermodynamic analysis. Propylene, dimethyl ether, ammonia, R-152a, propane, and HFE-152a all performed effectively in a 1 ton window unit and produced slightly lower emissions than the currently used R-22 and R-134a. The results suggest that regulation of HFCs in this application would have some effect on reducing emissions since end-of-life emissions remain at 55% of total refrigerant charge despite EPA regulations that mandate 80% recovery. Even so, offsite emissions due to energy generation dominate over direct GHG emissions and all the refrigerants perform similarly in totals of indirect GHG emissions.

  18. Split-flow regeneration in absorptive air separation

    DOEpatents

    Weimer, R.F.

    1987-11-24

    A chemical absorptive separation of air in multiple stage of absorption and desorption is performed with partial recycle of absorbent between stages of desorption necessary to match equilibrium conditions in the various stages of absorption. This allows reduced absorbent flow, reduced energy demand and reduced capital costs. 4 figs.

  19. Using Field-Metered Data to Quantify Annual Energy Use of Portable Air Conditioners

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Burke, Thomas; Willem, Henry; Ni, Chun Chun

    2014-12-12

    As many regions of the United States experience rising temperatures, consumers have come to rely increasingly on cooling appliances (including portable air conditioners) to provide a comfortable indoor temperature. Home occupants sometimes use a portable air conditioner (PAC) to maintain a desired indoor temperature in a single room or enclosed space. Although PACs in residential use are few compared to centrally installed and room air conditioning (AC) units, the past few years have witnessed an increase of PACs use throughout the United States. There is, however, little information and few research projects focused on the energy consumption and performance ofmore » PACs, particularly studies that collect information from field applications of PACs. The operation and energy consumption of PACs may differ among geographic locations and households, because of variations in cooling load, frequency, duration of use, and other user-selected settings. In addition, the performance of building envelope (thermal mass and air leakage) as well as inter-zonal mixing within the building would substantially influence the ability to control and maintain desirable indoor thermal conditions. Lawrence Berkeley National Laboratory (LBNL) conducted an initial field-metering study aimed at increasing the knowledge and data related to PAC operation and energy consumption in the United States. LBNL performed its field-metering study from mid-April to late October 2014. The study, which monitored 19 sites in the Northeastern United States (4 in upstate New York and 15 near Philadelphia), collected real-time data on PAC energy consumption along with information regarding housing characteristics, consumer behavior, and environmental conditions that were expected to affect PAC performance. Given the limited number of test sites, this study was not intended to be statistically representative of PAC users in the United States but rather to understand the system response to the cooling

  20. Space shuttle aps propellant thermal conditioner study

    NASA Technical Reports Server (NTRS)

    Fulton, D. L.

    1973-01-01

    An analytical and experimental effort was completed to evaluate a baffle type thermal conditioner for superheating O2 and H2 at supercritical pressures. The thermal conditioner consisted of a heat exchanger and an integral reactor (gas generator) operating on O2/H2 propellants. Primary emphasis was placed on the hydrogen conditioner with some effort on the oxygen conditioner and a study completed of alternate concepts for use in conditioning oxygen. A hydrogen conditioner was hot fire tested under a range of conditions to establish ignition, heat exchange and response parameters. A parallel technology task was completed to further evaluate the integral reactor and heat exchanger with the side mounted electrical spark igniter.

  1. 21 CFR 882.1845 - Physiological signal conditioner.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Physiological signal conditioner. 882.1845 Section... signal conditioner. (a) Identification. A physiological signal conditioner is a device such as an integrator or differentiator used to modify physiological signals for recording and processing. (b...

  2. 21 CFR 882.1845 - Physiological signal conditioner.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Physiological signal conditioner. 882.1845 Section... signal conditioner. (a) Identification. A physiological signal conditioner is a device such as an integrator or differentiator used to modify physiological signals for recording and processing. (b...

  3. Proposal of digital interface for the system of the air conditioner's remote control: analysis of the system of feedback.

    PubMed

    da Silva de Queiroz Pierre, Raisa; Kawada, Tarô Arthur Tavares; Fontes, André Guimarães

    2012-01-01

    Develop a proposal of digital interface for the system of the remote control, that functions as support system during the manipulation of air conditioner adjusted for the users in general, from ergonomic parameters, objectifying the reduction of the problems faced for the user and improving the process. 20 people with questionnaire with both qualitative and quantitative level. Linear Method consists of a sequence of steps in which the input of one of them depends on the output from the previous one, although they are independent. The process of feedback, when necessary, must occur within each step separately.

  4. Shuttle APS propellant thermal conditioner study

    NASA Technical Reports Server (NTRS)

    Pearson, W. E.

    1971-01-01

    A study program was performed to allow selection of thermal conditioner assemblies for superheating O2 and H2 at supercritical pressures. The application was the auxiliary propulsion system (APS) for the space shuttle vehicle. The O2/H2 APS propellant feed system included propellant conditioners, of which the thermal conditioner assemblies were a part. Cryogens, pumped to pressures above critical, were directed to the thermal conditioner assembly included: (1) a gas generator assembly with ignition system and bipropellant valves, which burned superheated O2 and H2 at rich conditions; (2) a heat exchanger assembly for thermal conditioning of the cryogenic propellant; and (3) a dump nozzle for heat exchanger exhaust.

  5. Aeroacoustic Characteristics of Model Jet Test Facility Flow Conditioners

    NASA Technical Reports Server (NTRS)

    Kinzie, Kevin W.; Henderson, Brenda S.; Haskin, Harry H.

    2005-01-01

    An experimental investigation of flow conditioning devices used to suppress internal rig noise in high speed, high temperature experimental jet facilities is discussed. The aerodynamic and acoustic characteristics of a number of devices including pressure loss and extraneous noise generation are measured. Both aerodynamic and acoustic characteristics are strongly dependent on the porosity of the flow conditioner and the closure ratio of the duct system. For unchoked flow conditioners, the pressure loss follows conventional incompressible flow models. However, for choked flow conditioners, a compressible flow model where the duct and flow conditioner system is modeled as a convergent-divergent nozzle can be used to estimate pressure loss. Choked flow conditioners generate significantly more noise than unchoked conditioners. In addition, flow conditioners with small hole diameters or sintered metal felt material generate less self-noise noise compared to flow conditioners with larger holes.

  6. A hybrid air conditioner driven by a hybrid solar collector

    NASA Astrophysics Data System (ADS)

    Al-Alili, Ali

    The objective of this thesis is to search for an efficient way of utilizing solar energy in air conditioning applications. The current solar Air Conditioners (A/C)s suffer from low Coefficient of Performance (COP) and performance degradation in hot and humid climates. By investigating the possible ways of utilizing solar energy in air conditioning applications, the bottlenecks in these approaches were identified. That resulted in proposing a novel system whose subsystem synergy led to a COP higher than unity. The proposed system was found to maintain indoor comfort at a higher COP compared to the most common solar A/Cs, especially under very hot and humid climate conditions. The novelty of the proposed A/C is to use a concentrating photovoltaic/thermal collector, which outputs thermal and electrical energy simultaneously, to drive a hybrid A/C. The performance of the hybrid A/C, which consists of a desiccant wheel, an enthalpy wheel, and a vapor compression cycle (VCC), was investigated experimentally. This work also explored the use of a new type of desiccant material, which can be regenerated with a low temperature heat source. The experimental results showed that the hybrid A/C is more effective than the standalone VCC in maintaining the indoor conditions within the comfort zone. Using the experimental data, the COP of the hybrid A/C driven by a hybrid solar collector was found to be at least double that of the current solar A/Cs. The innovative integration of its subsystems allows each subsystem to do what it can do best. That leads to lower energy consumption which helps reduce the peak electrical loads on electric utilities and reduces the consumer operating cost since less energy is purchased during the on peak periods and less solar collector area is needed. In order for the proposed A/C to become a real alternative to conventional systems, its performance and total cost were optimized using the experimentally validated model. The results showed that for an

  7. Importance of Air Absorption During Mechanical Integrity Testing

    NASA Astrophysics Data System (ADS)

    Arnold, Fredric C.

    1990-11-01

    Wells used for injection of liquid industrial waste into deep saline aquifers are required to be periodically tested for mechanical integrity. A generally accepted method to demonstrate mechanical integrity is to pressurize the casing-tubing annulus and monitor any decline in pressure. If air is used to pressurize the annulus, uncertainty may exist in differentiating between absorption of air into water in the annulus and loss of pressure due to the absence of mechanical integrity. An analytical model of air absorbance has been derived and used to quantify the pressure decline due to dissolving and diffusion of the air in annular water. A parameteric study was made to determine when annular pressure decline due to absorption of air is significant.

  8. Smart sensors enable smart air conditioning control.

    PubMed

    Cheng, Chin-Chi; Lee, Dasheng

    2014-06-24

    In this study, mobile phones, wearable devices, temperature and human motion detectors are integrated as smart sensors for enabling smart air conditioning control. Smart sensors obtain feedback, especially occupants' information, from mobile phones and wearable devices placed on human body. The information can be used to adjust air conditioners in advance according to humans' intentions, in so-called intention causing control. Experimental results show that the indoor temperature can be controlled accurately with errors of less than ±0.1 °C. Rapid cool down can be achieved within 2 min to the optimized indoor capacity after occupants enter a room. It's also noted that within two-hour operation the total compressor output of the smart air conditioner is 48.4% less than that of the one using On-Off control. The smart air conditioner with wearable devices could detect the human temperature and activity during sleep to determine the sleeping state and adjusting the sleeping function flexibly. The sleeping function optimized by the smart air conditioner with wearable devices could reduce the energy consumption up to 46.9% and keep the human health. The presented smart air conditioner could provide a comfortable environment and achieve the goals of energy conservation and environmental protection.

  9. Smart Sensors Enable Smart Air Conditioning Control

    PubMed Central

    Cheng, Chin-Chi; Lee, Dasheng

    2014-01-01

    In this study, mobile phones, wearable devices, temperature and human motion detectors are integrated as smart sensors for enabling smart air conditioning control. Smart sensors obtain feedback, especially occupants' information, from mobile phones and wearable devices placed on human body. The information can be used to adjust air conditioners in advance according to humans' intentions, in so-called intention causing control. Experimental results show that the indoor temperature can be controlled accurately with errors of less than ±0.1 °C. Rapid cool down can be achieved within 2 min to the optimized indoor capacity after occupants enter a room. It's also noted that within two-hour operation the total compressor output of the smart air conditioner is 48.4% less than that of the one using On-Off control. The smart air conditioner with wearable devices could detect the human temperature and activity during sleep to determine the sleeping state and adjusting the sleeping function flexibly. The sleeping function optimized by the smart air conditioner with wearable devices could reduce the energy consumption up to 46.9% and keep the human health. The presented smart air conditioner could provide a comfortable environment and achieve the goals of energy conservation and environmental protection. PMID:24961213

  10. [Detection of mite allergens in the dust of filter-net and air of air-conditioned room].

    PubMed

    Lian, Yu-yin; Liu, Zhi-gang; Wang, Hong-yu; Chai, Cheng-yu; Liu, Xiao-yu

    2007-08-01

    To detect mite allergens in the dust of air conditioner filter-net and floating air in room. Samples were collected from rooms of asthma patient and normal families with or without air conditioner. Der p1, Der f1 and Der 2 were determined by two monoclonal antibody-based ELISA. In asthma patient families, the concentration of airborne Der p1, Der f1 and Der 2 was (0.23 +/- 0.13), (2.62 +/- 1.08), (0.93 +/- 0.41) ng/m3, and (0.56 +/- 0.25), (4.74 +/- 1.22), (2.33 +/- 0.64) ng/m3 respectively before and after the air conditioner switched on, all showing a significant difference (P < 0.05). In families without asthma patient, the concentration of Der p1, Der f1 and Der 2 was (0.33 +/- 0.11), (11.50 +/- 3.08) and (2.10 +/- 0.80) ng/m3, and (0.63 +/- 0.23), (19.80 +/- 4.30) and (3.60 +/- 1.00) ng/m3 respectively before and after the air conditioner switched on, also showing a significant difference (P < 0.05). From the filter-net dust of air conditioner in family with allergic asthma patient, the concentration of Der p1, Der f1 and Der 2 was (0.52 +/- 0.19), (3.34 +/- 0.63), (2.53 +/- 0.65) microg/g dust, while that of normal families was (1.30 +/- 0.35), (5.16 +/- 0.92), (3.47 +/- 1.13) microg/g dust respectively. The concentration of Der f1 and Der 2 at both asthma families and normal families was higher than 2 microg/g, an allergen concentration threshold. Mite allergens exist in the filter-net dust of air conditioner, which may be an important source of indoor allergens and a cause of the increasing prevalence of allergic asthma.

  11. Low-frequency absorption of sound in air

    NASA Technical Reports Server (NTRS)

    Zuckerwar, A. J.; Meredith, R. W.

    1985-01-01

    Thirty sets of sound absorption measurements in air at a pressure of 1 atmosphere are presented at temperatures from 10 C to 50 C, relative humidities from 0 to 100 percent, and frequencies from 10 to 2500 Hz. The measurements were conducted by the method of free decay in a resonant tube having a length of 18.261 m and bore diameter of 0.152 m. Background measurements in a gas consisting of 89.5 percent N2 and 10.5 percent Ar, a mixture which has the same sound velocity as air, permitted the wall and structural losses of the tube to be separated from the constituent absorption, consisting of classical rotational and vibrational absorption, in the air samples. The data were used to evaluate the vibrational relaxation frequencies of N2 and/or O2 for each of the 30 sets of meteorological parameters. Over the full range of humidity, the measured relaxation frequencies of N2 in air lie between those specified by ANSI Standard S1.26-1978 and those measured earlier in binary N2H2O mixtures. The measured relaxation frequencies could be determined only at very low values of humidity, reveal a significant trend away from the ANSI standard, in agreement with a prior investigation.

  12. Low-frequency sound absorption measurements in air

    NASA Technical Reports Server (NTRS)

    Zuckerwar, A. J.; Meredith, R. W.

    1984-01-01

    Thirty sets of sound absorption measurements in air at a pressure of 1 atmosphere are presented at temperatures from 10 C to 50 C, relative humidities from 0 to 100 percent, and frequencies from 10 to 2500 Hz. The measurements were conducted by the method of free decay in a resonant tube having a length of 18.261 m and bore diameter of 0.152 m. Background measurements in a gas consisting of 89.5 percent N2 and 10.5 percent Ar, a mixture which has the same sound velocity as air, permitted the wall and structural losses of the tube to be separated from the constituent absorption, consisting of classical rotational and vibrational absorption, in the air samples. The data were used to evaluate the vibrational relaxation frequencies of N2 and/or O2 for each of the 30 sets of meteorological parameters. Over the full range of humidity, the measured relaxation frequencies of N2 in air lie between those specified by ANSI Standard S1.26-1978 and those measured earlier in binary N2H2O mixtures. The measured relaxation frequencies could be determined only at very low values of humidity, reveal a significant trend away from the ANSI standard, in agreement with a prior investigation.

  13. Effects of a non-rinse conditioner on the enamel of primary teeth.

    PubMed

    Fava, Marcelo; Myaki, Silvio Issáo; Arana-Chavez, Victor Elias; Fava-de-Moraes, Flavio

    2003-01-01

    The aim of this in vitro study was to evaluate by scanning electron microscopy the morphological aspects of the enamel of primary teeth after etching with 36% phosphoric acid or a non-rinse conditioner. Ten naturally exfoliated anterior primary teeth were selected. The samples were subjected to prophylaxis with pumice paste and water using a low-speed hand piece. Etching was done on the buccal surface. Specimens were divided into 2 groups: G1 (n=10): etching with 36% phosphoric acid gel - Conditioner 36 (Dentsply) for 20 s, followed by water rinse for 15 s; G2 (n=10): etching with NRC - Non Rinse Conditioner (Dentsply) for 20 s, followed by air drying for 15 s. The samples were dehydrated, mounted on metal stubs, coated with gold and observed with Jeol JSM-6100 scanning electron microscope. Electron-micrographic analysis showed that both etching agents were effective for etching the enamel of primary teeth causing the formation of microporosities on the enamel surface, although the etching pattern was more effective with the use of 36% phosphoric acid gel.

  14. Auto-ignition of lubricating oil working at high pressures in a compressor for an air conditioner.

    PubMed

    Kim, Chul Jin; Choi, Hyo Hyun; Sohn, Chae Hoon

    2011-01-15

    Auto-ignition of lubricating oil working in a compressor for an air conditioner is studied experimentally. The adopted lubricating oil is an unknown mixture with multi-components and known to have flash point temperature of 170 °C. First, its auto-ignition temperature is measured 365 °C at atmospheric pressure. The lubricating oil works under high-pressure condition up to 30 atm and it is heated and cooled down repeatedly. Accordingly, auto-ignition temperatures or flammable limits of lubricating oil are required at high pressures with respect to fire safety. Because there is not a standard test method for the purpose, a new ignition-test method is proposed in this study and thereby, auto-ignition temperatures are measured over the pressure range below 30 atm. The measured temperatures range from 215 °C to 255 °C and they strongly depend on pressure of gas mixture consisting of oil vapor, nitrogen, and oxygen. They are close to flash point temperature and the lubricating oil can be hazardous when it works for high-pressure operating condition and abundant air flows into a compressor. Copyright © 2010 Elsevier B.V. All rights reserved.

  15. Influence of surrounding structures upon the aerodynamic and acoustic performance of the outdoor unit of a split air-conditioner

    NASA Astrophysics Data System (ADS)

    Wu, Chengjun; Liu, Jiang; Pan, Jie

    2014-07-01

    DC-inverter split air-conditioner is widely used in Chinese homes as a result of its high-efficiency and energy-saving. Recently, the researches on its outdoor unit have focused on the influence of surrounding structures upon the aerodynamic and acoustic performance, however they are only limited to the influence of a few parameters on the performance, and practical design of the unit requires more detailed parametric analysis. Three-dimensional computational fluid dynamics(CFD) and computational aerodynamic acoustics(CAA) simulation based on FLUENT solver is used to study the influence of surrounding structures upon the aforementioned properties of the unit. The flow rate and sound pressure level are predicted for different rotating speed, and agree well with the experimental results. The parametric influence of three main surrounding structures(i.e. the heat sink, the bell-mouth type shroud and the outlet grille) upon the aerodynamic performance of the unit is analyzed thoroughly. The results demonstrate that the tip vortex plays a major role in the flow fields near the blade tip and has a great effect on the flow field of the unit. The inlet ring's size and throat's depth of the bell-mouth type shroud, and the through-flow area and configuration of upwind and downwind sections of the outlet grille are the most important factors that affect the aerodynamic performance of the unit. Furthermore, two improved schemes against the existing prototype of the unit are developed, which both can significantly increase the flow rate more than 6 %(i.e. 100 m3·h-1) at given rotating speeds. The inevitable increase of flow noise level when flow rate is increased and the advantage of keeping a lower rotating speed are also discussed. The presented work could be a useful guideline in designing the aerodynamic and acoustic performance of the split air-conditioner in engineering practice.

  16. Thermophysics Characterization of Multiply Ionized Air Plasma Absorption of Laser Radiation

    NASA Technical Reports Server (NTRS)

    Wang, Ten-See; Rhodes, Robert; Turner, Jim (Technical Monitor)

    2002-01-01

    The impact of multiple ionization of air plasma on the inverse Bremsstrahlung absorption of laser radiation is investigated for air breathing laser propulsion. Thermochemical properties of multiply ionized air plasma species are computed for temperatures up to 200,000 deg K, using hydrogenic approximation of the electronic partition function; And those for neutral air molecules are also updated for temperatures up to 50,000 deg K, using available literature data. Three formulas for absorption are calculated and a general formula is recommended for multiple ionization absorption calculation. The plasma composition required for absorption calculation is obtained by increasing the degree of ionization sequentially, up to quadruple ionization, with a series of thermal equilibrium computations. The calculated second ionization absorption coefficient agrees reasonably well with that of available data. The importance of multiple ionization modeling is demonstrated with the finding that area under the quadruple ionization curve of absorption is found to be twice that of single ionization. The effort of this work is beneficial to the computational plasma aerodynamics modeling of laser lightcraft performance.

  17. Model-based optimizations of packaged rooftop air conditioners using low global warming potential refrigerants

    DOE PAGES

    Shen, Bo; Abdelaziz, Omar; Shrestha, Som; ...

    2017-10-31

    Based on laboratory investigations for R-22 and R-410A alternative low GWP refrigerants in two baseline rooftop air conditioners (RTU), the DOE/ORNL Heat Pump Design Model was used to model the two RTUs and the models were calibrated against the experimental data. We compared the compressor efficiencies and heat exchanger performances. An efficiency-based compressor mapping method was developed. Extensive model-based optimizations were conducted to provide a fair comparison between all the low GWP candidates by selecting optimal configurations. The results illustrate that all the R-22 low GWP refrigerants will lead to slightly lower COPs. ARM-20B appears to be the best R-22more » replacement at normal conditions. At higher ambient temperatures, ARM-20A exhibits better performance. All R-410A low GWP candidates will result in similar or better efficiencies than R-410A. R-32 has the best COP while requiring the smallest compressor. Finally, R-452B uses the closest compressor displacement volume and achieves the same efficiency as R-410A.« less

  18. Model-based optimizations of packaged rooftop air conditioners using low global warming potential refrigerants

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Shen, Bo; Abdelaziz, Omar; Shrestha, Som

    Based on laboratory investigations for R-22 and R-410A alternative low GWP refrigerants in two baseline rooftop air conditioners (RTU), the DOE/ORNL Heat Pump Design Model was used to model the two RTUs and the models were calibrated against the experimental data. We compared the compressor efficiencies and heat exchanger performances. An efficiency-based compressor mapping method was developed. Extensive model-based optimizations were conducted to provide a fair comparison between all the low GWP candidates by selecting optimal configurations. The results illustrate that all the R-22 low GWP refrigerants will lead to slightly lower COPs. ARM-20B appears to be the best R-22more » replacement at normal conditions. At higher ambient temperatures, ARM-20A exhibits better performance. All R-410A low GWP candidates will result in similar or better efficiencies than R-410A. R-32 has the best COP while requiring the smallest compressor. Finally, R-452B uses the closest compressor displacement volume and achieves the same efficiency as R-410A.« less

  19. 7 CFR 3201.92 - Fuel conditioners.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 7 Agriculture 15 2013-01-01 2013-01-01 false Fuel conditioners. 3201.92 Section 3201.92... Designated Items § 3201.92 Fuel conditioners. (a) Definition. Products formulated to improve the performance... fuel system. (b) Minimum biobased content. The Federal preferred procurement product must have a...

  20. 7 CFR 3201.92 - Fuel conditioners.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 7 Agriculture 15 2014-01-01 2014-01-01 false Fuel conditioners. 3201.92 Section 3201.92... Designated Items § 3201.92 Fuel conditioners. (a) Definition. Products formulated to improve the performance... fuel system. (b) Minimum biobased content. The Federal preferred procurement product must have a...

  1. Lemongrass-Incorporated Tissue Conditioner Against Candida albicans Culture

    PubMed Central

    Amornvit, Pokpong; Srithavaj, Theerathavaj

    2014-01-01

    Background: Tissue conditioner is applied popularly with dental prosthesis during wound healing process but it becomes a reservoir of oral microbiota, especially Candida species after long-term usage. Several antifungal drugs have been mixed with this material to control fungal level. In this study, lemongrass essential oil was added into COE-COMFORT tissue conditioner before being determined for anti-Candida efficacy. Materials and Methods: Lemongrass (Cymbopogon citratus) essential oil was primarily determined for antifungal activity against C. albicans American type culture collection (ATCC) 10231 and MIC (minimum inhibitory concentration) value by agar disk diffusion and broth microdilution methods, respectively. COE-COMFORT tissue conditioner was prepared as recommended by the manufacturer after a fixed volume of the oil at its MIC or higher concentrations were mixed thoroughly in its liquid part. Antifungal efficacy of the tissue conditioner with/without herb was finally analyzed. Results: Lemongrass essential oil displayed potent antifungal activity against C. albicans ATCC 10231and its MIC value was 0.06% (v/v). Dissimilarly, the tissue conditioner containing the oil at MIC level did not cease the growth of the tested fungus. Both reference and clinical isolates of C. albicans were completely inhibited after exposed to the tissue conditioner containing at least 0.25% (v/v) of the oil (approximately 4-time MIC). The tissue conditioner without herb or with nystatin was employed as negative or positive control, respectively. Conclusion: COE-COMFORT tissue conditioner supplemented with lemongrass essential oil obviously demonstrated another desirable property as in vitro anti-Candida efficacy to minimize the risk of getting Candidal infection. PMID:25177638

  2. Roseomonas aerofrigidensis sp. nov., isolated from an air conditioner.

    PubMed

    Hyeon, Jong Woo; Jeon, Che Ok

    2017-10-01

    A Gram-stain-negative, strictly aerobic bacterium, designated HC1 T , was isolated from an air conditioner in South Korea. Cells were orange, non-motile cocci with oxidase- and catalase-positive activities and did not contain bacteriochlorophyll a. Growth of strain HC1 T was observed at 10-45 °C (optimum, 30 °C), pH 4.5-9.5 (optimum, pH 7.0) and 0-3 % (w/v) NaCl (optimum, 0 %). Strain HC1 T contained summed feature 8 (comprising C18 : 1ω7c/C18 : 1ω6c), C16 : 0 and cyclo-C19 : 0ω8c as the major fatty acids and ubiquinone-10 as the sole isoprenoid quinone. Phosphatidylglycerol, phosphatidylethanolamine, phosphatidylcholine and an unknown aminolipid were detected as the major polar lipids. The major carotenoid was hydroxyspirilloxanthin. The G+C content of the genomic DNA was 70.1 mol%. Phylogenetic analysis, based on 16S rRNA gene sequences, showed that strain HC1 T formed a phylogenetic lineage within the genus Roseomonas. Strain HC1 T was most closely related to the type strains of Roseomonas oryzae, Roseomonas rubra, Roseomonas aestuarii and Roseomonas rhizosphaerae with 98.1, 97.9, 97.6 and 96.8 % 16S rRNA gene sequence similarities, respectively, but the DNA-DNA relatedness values between strain HC1 T and closely related type strains were less than 70 %. Based on phenotypic, chemotaxonomic and molecular properties, strain HC1 T represents a novel species of the genus Roseomonas, for which the name Roseomonas aerofrigidensis sp. nov. is proposed. The type strain is HC1 T (=KACC 19097 T =JCM 31878 T ).

  3. Keeping cool: use of air conditioning by australians with multiple sclerosis.

    PubMed

    Summers, Michael P; Simmons, Rex D; Verikios, George

    2012-01-01

    Despite the known difficulties many people with MS have with high ambient temperatures, there are no reported studies of air conditioning use and MS. This study systematically examined air conditioner use by Australians with MS. A short survey was sent to all participants in the Australian MS Longitudinal Study cohort with a response rate of 76% (n = 2,385). Questions included hours of air-conditioner use, areas cooled, type and age of equipment, and the personal effects of overheating. Air conditioners were used by 81.9% of respondents, with an additional 9.6% who could not afford an air conditioner. Regional and seasonal variation in air conditioning use was reported, with a national annual mean of 1,557 hours running time. 90.7% reported negative effects from overheating including increased fatigue, an increase in other MS symptoms, reduced household and social activities, and reduced work capacity. Households that include people with MS spend between 4 and 12 times more on keeping cool than average Australian households.

  4. Triple-effect absorption chiller cycle: A step beyond double-effect cycles

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    DeVault, R.C.

    1990-01-01

    Many advanced'' absorption cycles have been proposed during the current century. Of the hundreds of absorption cycles which have been patented throughout the world, all commercially manufactured products for air conditioning buildings have been variations of just two basic absorption cycles: single-effect and condenser-coupled double-effect cycles. The relatively low cooling coefficients of performance (COPs) inherent in single-effect and double-effect cycles limits the economic applicability of absorption air conditioners (chillers) in the United States. A triple-effect absorption chiller cycle is discussed. This cycle uses two condensers and two absorbers to achieve the triple effect.'' Depending on the absorption fluids selected, thismore » triple-effect cycle is predicted to improve cooling COPs by 18% to 60% compared with the equivalent double-effect cycle. This performance improvement is obtained without increasing the total amount of heat-transfer surface area needed for the heat exchangers. A comparison between the calculated performances of a double-effect cycle and a triple-effect cycle (both using ammonia-water (NH{sub 3}/H{sub 2}O) as the absorption fluid pair) is presented. The triple-effect cycle is predicted to have an 18% higher cooling COP (1.41 compared with 1.2 for a double-effect), lower pressure (47.70 atm (701 psi) instead of 68.05 atm (1000 psi)), significantly reduced pumping power (less than one-half that of the double-effect cycle), and potentially lower construction cost (33% less total heat exchange needed). Practical implications for this triple-effect cycle are discussed. 16 refs., 5 figs., 1 tab.« less

  5. Absorption generator for solar-powered air-conditioner

    NASA Technical Reports Server (NTRS)

    Lowen, D. J.; Murray, J. G.

    1977-01-01

    Device passes solar-heated water through coils. Hot lithium Bromide/Water solution leaves through central stand-pipe, and water vapor leaves through refrigerant outlet at top. Matching generation temperature to collector efficiency helps cut costs.

  6. Seminar 14 - Desiccant Enhanced Air Conditioning: Desiccant Enhanced Evaporative Air Conditioning (Presentation)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kozubal, E.

    2013-02-01

    This presentation explains how liquid desiccant based coupled with an indirect evaporative cooler can efficiently produce cool, dry air, and how a liquid desiccant membrane air conditioner can efficiently provide cooling and dehumidification without the carryover problems of previous generations of liquid desiccant systems. It provides an overview to a liquid desiccant DX air conditioner that can efficiently provide cooling and dehumidification to high latent loads without the need for reheat, explains how liquid desiccant cooling and dehumidification systems can outperform vapor compression based air conditioning systems in hot and humid climates, explains how liquid desiccant cooling and dehumidification systemsmore » work, and describes a refrigerant free liquid desiccant based cooling system.« less

  7. Technical and Economic Aspects of Designing an Efficient Room Air-Conditioner Program in India

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Abhyankar, Nikit; Shah, Nihar; Phadke, Amol

    Several studies have projected a massive increase in the demand for air conditioners (ACs) over the next two decades in India. By 2030, room ACs could add 140 GW to the peak load, equivalent to over 30% of the total projected peak load. Therefore, there is significant interest among policymakers, regulators, and utilities in managing room AC demand by enhancing energy efficiency. Building on the historical success of the Indian Bureau of Energy Efficiency’s star-labeling program, Energy Efficiency Services Limited recently announced a program to accelerate the sale of efficient room ACs using bulk procurement, similar to their successful UJALAmore » light-emitting diode (LED) bulk procurement program. This report discusses some of the key considerations in designing a bulk procurement or financial incentive program for enhancing room AC efficiency in India. We draw upon our previous research to demonstrate the overall technical potential and price impact of room AC efficiency improvement and its technical feasibility in India. We also discuss the importance of using low global warming potential (GWP) refrigerants and smart AC equipment that is demand response (DR) ready.« less

  8. Effect of metal conditioner on bonding of porcelain to cobalt-chromium alloy

    PubMed Central

    Kajihara, Yutaro; Takenouchi, Yoshihisa; Tanaka, Takuo; Suzuki, Shiro; Minami, Hiroyuki

    2016-01-01

    PURPOSE The purpose of this study was to evaluate the efficacy of two different metal conditioners for non-precious metal alloys for the bonding of porcelain to a cobalt-chromium (Co-Cr) alloy. MATERIALS AND METHODS Disk-shaped specimens (2.5×10.0 mm) were cast with Co-Cr alloy and used as adherend materials. The bonding surfaces were polished with a 600-grid silicon carbide paper and airborne-particle abraded using 110 µm alumina particles. Bonding specimens were fabricated by applying and firing either of the metal conditioners on the airborne-particle abraded surface, followed by firing porcelain into 5 mm in diameter and 3 mm in height. Specimens without metal conditioner were also fabricated. Shear bond strength for each group (n=8) were measured and compared (α=.05). Sectional view of bonding interface was observed by SEM. EDS analysis was performed to determine the chemical elements of metal conditioners and to determine the failure modes after shear test. RESULTS There were significant differences among three groups, and two metal conditioner-applied groups showed significantly higher values compared to the non-metal conditioner group. The SEM observation of the sectional view at bonding interface revealed loose contact at porcelain-alloy surface for non-metal conditioner group, however, close contact at both alloy-metal conditioner and metal conditioner-porcelain interfaces for both metal conditioner-applied groups. All the specimens showed mixed failures. EDS analysis showed that one metal conditioner was Si-based material, and another was Ti-based material. Si-based metal conditioner showed higher bond strengths compared to the Ti-based metal conditioner, but exhibited more porous failure surface failure. CONCLUSION Based on the results of this study, it can be stated that the application of metal conditioner is recommended for the bonding of porcelain to cobalt-chromium alloys. PMID:26949481

  9. Keeping Cool: Use of Air Conditioning by Australians with Multiple Sclerosis

    PubMed Central

    Summers, Michael P.; Simmons, Rex D.; Verikios, George

    2012-01-01

    Despite the known difficulties many people with MS have with high ambient temperatures, there are no reported studies of air conditioning use and MS. This study systematically examined air conditioner use by Australians with MS. A short survey was sent to all participants in the Australian MS Longitudinal Study cohort with a response rate of 76% (n = 2,385). Questions included hours of air-conditioner use, areas cooled, type and age of equipment, and the personal effects of overheating. Air conditioners were used by 81.9% of respondents, with an additional 9.6% who could not afford an air conditioner. Regional and seasonal variation in air conditioning use was reported, with a national annual mean of 1,557 hours running time. 90.7% reported negative effects from overheating including increased fatigue, an increase in other MS symptoms, reduced household and social activities, and reduced work capacity. Households that include people with MS spend between 4 and 12 times more on keeping cool than average Australian households. PMID:22548176

  10. Shuttle APS propellant thermal conditioner study

    NASA Technical Reports Server (NTRS)

    Fulton, D. L.

    1971-01-01

    The conditioner design concept selected for evaluation consists of an integral reactor and baffle-type heat exchanger. Heat exchange is accomplished by flowing reactor hot gases past a series of slotted and formed plates, through which the conditioned propellant flows. Heat transfer analysis has resulted in the selection of a reactor hot gas nominal mixture ratio of 1.0, giving a combustion temperature of 1560 F with a hydrogen inlet temperature of 275 R. Worst case conditions result in a combustion gas temperature of 2060 F, satisfying the condition of no damage to the conditioner in case of failure to flow cold fluid. In addition, evaluation of hot gas flow requirements and conditioner weight has resulted in the selection of a reactor hot gas exhaust temperature of 750 R.

  11. Evaluation of Alternative Refrigerants for Mini-Split Air Conditioners

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Abdelaziz, Omar; Shrestha, Som S

    The phase-out of hydrochlorofluorocarbons (HCFC) refrigerants in developing countries is currently underway according to the Montreal Protocol. R-22 is one of the most commonly used HCFCs in the developing nations. It is extremely well suited for air conditioning and refrigeration (AC&R) in high ambient temperature environments. Non-Article 5 countries have already gone through the phase-out of HCFCs and settled on using R-410A as the refrigerant of choice for AC applications. Previous studies have shown that R-410A results in significant capacity and performance degradation at higher ambient temperature conditions. As such, there is a growing concern on finding alternative refrigerants tomore » R-22 that would have zero ODP, lower GWP, and at the same time maintain acceptable performance at higher ambient temperatures. Furthermore, the developed world s transition through higher global warming potential (GWP) refrigerants like HFC and HFC blends resulted in significant direct CO2 equivalent emissions. It is imperative to develop a bridge for developing nations to avoid the transition from HCFC to HFC and then from HFC to alternative lower GWP refrigerants. This paper summarizes data from an experimental campaign on alternative refrigerant evaluation for R-22 and R-410A substitutes for mini-split air conditioners designed for high ambient environments. The experimental evaluation was performed according to ANSI/ASHRAE Standard 37 and the performance was rated at test conditions specified by ANSI/AHRI 210-240 and ISO 5151. Additional tests were conducted at outdoor ambient temperatures of 52 C (125.6 F) and 55 C (131 F) to evaluate their performance at high ambient conditions. Alternative refrigerants, some of which are proprietary, included R-444B, DR-3, N-20b, ARM-20b, R-290, and DR-93 as alternatives to R-22 and R-32, DR-55, L41-2, ARM-71A, and HPR-2A as alternatives to R-410A. The units performances were first verified using the baseline refrigerant and then

  12. 21 CFR 872.3750 - Bracket adhesive resin and tooth conditioner.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Bracket adhesive resin and tooth conditioner. 872... SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3750 Bracket adhesive resin and tooth conditioner. (a) Identification. A bracket adhesive resin and tooth conditioner is a device...

  13. 21 CFR 872.3765 - Pit and fissure sealant and conditioner.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Pit and fissure sealant and conditioner. 872.3765 Section 872.3765 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... conditioner. (a) Identification. A pit and fissure sealant and conditioner is a device composed of resin, such...

  14. 21 CFR 872.3765 - Pit and fissure sealant and conditioner.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Pit and fissure sealant and conditioner. 872.3765 Section 872.3765 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES... conditioner. (a) Identification. A pit and fissure sealant and conditioner is a device composed of resin, such...

  15. 10 CFR 429.43 - Commercial heating, ventilating, air conditioning (HVAC) equipment.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... seasonal energy efficiency ratio (SEER in British thermal units per Watt-hour (Btu/Wh)), the heating...) Package terminal air conditioners: The energy efficiency ratio (EER in British thermal units per Watt-hour... package vertical air conditioner: The energy efficiency ratio (EER in British thermal units per Watt-hour...

  16. 10 CFR 429.43 - Commercial heating, ventilating, air conditioning (HVAC) equipment.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... seasonal energy efficiency ratio (SEER in British thermal units per Watt-hour (Btu/Wh)), the heating...) Package terminal air conditioners: The energy efficiency ratio (EER in British thermal units per Watt-hour... package vertical air conditioner: The energy efficiency ratio (EER in British thermal units per Watt-hour...

  17. Incidence of polybrominated diphenyl ethers in central air conditioner filter dust from a new office building.

    PubMed

    Ni, Hong-Gang; Cao, Shan-Ping; Chang, Wen-Jing; Zeng, Hui

    2011-07-01

    This study examined polybrominated diphenyl ethers (PBDEs) in central air conditioner filter (CACF) dust from a new office building in Shenzhen, China. Human exposure to PBDE via dust inhalation and ingestion were also estimated. PBDEs level in CACF dust was lower than those in the other countries and regions. Approximately 0.671 pg/kg bw/day PM(2.5) (Particulate Matter up to 2.5 μm in size) bounded Σ(15)PBDEs can be inhaled deep into the lungs and 4.123 pg/kg bw/day PM(10) (Particulate Matter up to 10 μm in size) bounded Σ(15)PBDEs tend to be deposited in the upper parts of the respiratory system. The average total intake of Σ(15)PBDEs via dust inhalation and ingestion for adults reached ∼ 141 pg/kg bw/day in this building. This value was far below the reference dose (RfD) recommended by United States Environmental Protection Agency. Human exposure to PBDEs via dust inhalation and ingestion in the new building is less than the old ones. Copyright © 2010 Elsevier Ltd. All rights reserved.

  18. Cost-Benefit of Improving the Efficiency of Room Air Conditioners (Inverter and Fixed Speed) in India

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Phadke, Amol; Shah, Nihar; Abhyankar, Nikit

    Improving efficiency of air conditioners (ACs) typically involves improving the efficiency of various components such as compressors, heat exchangers, expansion valves, refrigerant,and fans. We estimate the incremental cost of improving the efficiency of room ACs based on the cost of improving the efficiency of its key components. Further, we estimate the retail price increase required to cover the cost of efficiency improvement, compare it with electricity bill savings, and calculate the payback period for consumers to recover the additional price of a more efficient AC. The finding that significant efficiency improvement is cost effective from a consumer perspective is robustmore » over a wide range of assumptions. If we assume a 50% higher incremental price compared to our baseline estimate, the payback period for the efficiency level of 3.5 ISEER is 1.1 years. Given the findings of this study, establishing more stringent minimum efficiency performance criteria (one-star level) should be evaluated rigorously considering significant benefits to consumers, energy security, and environment« less

  19. Antifungal Effect of a Dental Tissue Conditioner Containing Nystatin-Loaded Alginate Microparticles.

    PubMed

    Kim, Hyun-Jin; Son, Jun Sik; Kwon, Tae-Yub

    2018-02-01

    In this in vitro study, nystatin-alginate microparticles were successfully fabricated to control the release of nystatin from a commercial dental tissue conditioner. These nystatin-alginate microparticles were spherical and had a slightly rough surface. The microparticles incorporated into the tissue conditioner were distributed homogeneously throughout the tissue conditioner matrix. The incorporation of the microparticles did not deteriorate the mechanical properties of the original material. The agar diffusion test results showed that the tissue conditioner containing the microparticles had a good antifungal effect against Candida albicans. The nystatin-alginate microparticles efficiently controlled the release of nystatin from the tissue conditioner matrix over the experimental period of 14 days. Moreover, the nystatin-alginate microparticles incorporated in the tissue conditioner showed effective antifungal function even at lower concentrations of nystatin. The current study suggests that the tissue conditioner containing the nystatin-alginate microparticle carrier system has potential as an effective antifungal material.

  20. Formulation of humic-based soil conditioners

    NASA Astrophysics Data System (ADS)

    Amanova, M. A.; Mamytova, G. A.; Mamytova, B. A.; Kydralieva, K. A.; Jorobekova, Sh. J.

    2009-04-01

    The goal of the study is to prepare soil conditioners (SC) able to carry out the following functions: (i) the chemical conditioning of soil mainly comprising the adjustment of pH, (ii) the balancing of inorganic nutrients, (iii) the physical conditioning of soil mainly comprising the improvement of water permeability, air permeability and water retention properties, and (iv) improvement of the ecological system concerning of useful microorganisms activity in the soil. The SC was made of a mixture of inorganic ingredients, a chemical composition and physical and chemical properties of which promoted improvement of physical characteristic of soil and enrichment by its mineral nutritious elements. In addition to aforesaid ingredients, this soil conditioner contains agronomical-valued groups of microorganisms having the function promoting the growth of the crop. As organic component of SC humic acids (HA) was used. HA serve many major functions that result in better soil and plant health. In soil, HA can increase microbial and mycorrhizal activity while enhancing nutrient uptake by plant roots. HA work as a catalyst by stimulating root and plant growth, it may enhance enzymatic activity that in turn accelerates cell division which can lead to increased yields. HA can help to increase crop yields, seed germination, and much more. In short, humic acids helps keep healthy plants health. The first stage goal was to evaluate mineral and organic ingredients for formulation of SC. Soil conditioners assessed included ash and slag. The use of slags has been largelly used in agriculture as a source of lime and phosphoric acid. The silicic acid of slags reduces Al-acitivity thus, promoting a better assimilation of P-fertilizer by plants. Additionally, silicic acid is also known to improve soil moisture capacity, thus enhancing soil water availability to plants. Physico-chemical characteristics of ash and slag were determined, as a total - about 20 samples. Results include

  1. Methodology for Automated Detection of Degradation and Faults in Packaged Air Conditioners and Heat Pumps Using Only Two Sensors

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    2016-02-10

    The software was created in the process of developing a system known as the Smart Monitoring and Diagnostic System (SMDS) for packaged air conditioners and heat pumps used on commercial buildings (known as RTUs). The SMDS provides automated remote monitoring and detection of performance degradation and faults in these RTUs and could increase the awareness by building owners and maintenance providers of the condition of the equipment, the cost of operating it in degraded condition, and the quality of maintenance and repair service when it is performed. The SMDS provides these capabilities and would enable conditioned-based maintenance rather than themore » reactive and schedule-based preventive maintenance commonly used today, when maintenance of RTUs is done at all. Improved maintenance would help ensure persistent peak operating efficiencies, reducing energy consumption by an estimated 10% to 30%.« less

  2. Test Program for Evaluation of Variable Frequency Power Conditioners

    DOT National Transportation Integrated Search

    1973-08-01

    A test program is outlined for variable frequency power conditioners for 3-phase induction motors in vehicle propulsion applications. The Power Conditioner Unit (PCU) performance characteristics are discussed in some detail. Measurement methods, reco...

  3. Allergies to molds caused by fungal spores in air conditioning equipment

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Schata, M.; Jorde, W.; Elixmann, J.H.

    1989-01-01

    People suffering from various symptoms while in air-conditioned rooms often show sensitizations to fungi that can be isolated when the fungi are removed from air conditioners. By using specific challenge tests it was shown that fungal spores in air conditioners can evoke allergic symptoms. Hyposensitization was the specific therapy prescribed for such allergic reactions. After hyposensitization therapy, more than 70% of the patients so treated could live and work again in air-conditioned rooms without developing specific symptoms.

  4. Photovoltaic array: Power conditioner interface characteristics

    NASA Technical Reports Server (NTRS)

    Gonzalez, C. C.; Hill, G. M.; Ross, R. G., Jr.

    1982-01-01

    The electrical output (power, current, and voltage) of flat plate solar arrays changes constantly, due primarily to changes in cell temperature and irradiance level. As a result, array loads such as dc-to-ac power conditioners must be capable of accommodating widely varying input levels while maintaining operation at or near the maximum power point of the array. The array operating characteristics and extreme output limits necessary for the systematic design of array load interfaces under a wide variety of climatic conditions are studied. A number of interface parameters are examined, including optimum operating voltage, voltage energy, maximum power and current limits, and maximum open circuit voltage. The effect of array degradation and I-V curve fill factor or the array power conditioner interface is also discussed. Results are presented as normalized ratios of power conditioner parameters to array parameters, making the results universally applicable to a wide variety of system sizes, sites, and operating modes.

  5. Air Conditioning with Magnetic Refrigeration : An Efficient, Green Compact Cooling System Using Magnetic Refrigeration

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    None

    2010-09-01

    BEETIT Project: Astronautics is developing an air conditioning system that relies on magnetic fields. Typical air conditioners use vapor compression to cool air. Vapor compression uses a liquid refrigerant to circulate within the air conditioner, absorb the heat, and pump the heat out into the external environment. Astronautics’ design uses a novel property of certain materials, called “magnetocaloric materials”, to achieve the same result as liquid refrigerants. These magnetocaloric materials essentially heat up when placed within a magnetic field and cool down when removed, effectively pumping heat out from a cooler to warmer environment. In addition, magnetic refrigeration uses nomore » ozone-depleting gases and is safer to use than conventional air conditioners which are prone to leaks.« less

  6. Rheology of tissue conditioners.

    PubMed

    Murata, H; Hamada, T; Djulaeha, E; Nikawa, H

    1998-02-01

    Tissue conditioners can be used to condition abused tissues, record functional impressions, make temporary relinings, and for other clinical applications, mainly because of their specific viscoelasticity. However, little information is available on the rheology of the materials, manipulation, and suitability for various clinical applications. This study evaluated the gelation times, the viscoelastic properties after gelation of tissue conditioners, and the influence of the powder/liquid (P/L) ratio. Ten tissue conditioners were used and gelation times were obtained with an oscillating rheometer. A series of stress relaxation tests were also conducted to evaluate the viscoelastic properties after gelation and the changes with the passage of time by means of Maxwell model analogies. Significant differences were found in the gelation times and flow properties after gelation among the materials mixed with the P/L ratios recommended by the manufacturers. The flow properties tended to increase with time of storage. Large differences in the limits of the clinically acceptable P/L ratios and the adjustable limits of elasticity and viscosity by altering P/L ratios were found among the materials. The results suggested that each material should be selected according to each clinical purpose because of the wide ranges of viscoelastic properties and changes in viscoelasticity with time among the materials. Furthermore, gelation times and the viscoelastic properties after gelation can be controlled to improve handling and suit various applications by altering the P/L ratios within the acceptable limits.

  7. Advanced Signal Conditioners for Data-Acquisition Systems

    NASA Technical Reports Server (NTRS)

    Lucena, Angel; Perotti, Jose; Eckhoff, Anthony; Medelius, Pedro

    2004-01-01

    Signal conditioners embodying advanced concepts in analog and digital electronic circuitry and software have been developed for use in data-acquisition systems that are required to be compact and lightweight, to utilize electric energy efficiently, and to operate with high reliability, high accuracy, and high power efficiency, without intervention by human technicians. These signal conditioners were originally intended for use aboard spacecraft. There are also numerous potential terrestrial uses - especially in the fields of aeronautics and medicine, wherein it is necessary to monitor critical functions. Going beyond the usual analog and digital signal-processing functions of prior signal conditioners, the new signal conditioner performs the following additional functions: It continuously diagnoses its own electronic circuitry, so that it can detect failures and repair itself (as described below) within seconds. It continuously calibrates itself on the basis of a highly accurate and stable voltage reference, so that it can continue to generate accurate measurement data, even under extreme environmental conditions. It repairs itself in the sense that it contains a micro-controller that reroutes signals among redundant components as needed to maintain the ability to perform accurate and stable measurements. It detects deterioration of components, predicts future failures, and/or detects imminent failures by means of a real-time analysis in which, among other things, data on its present state are continuously compared with locally stored historical data. It minimizes unnecessary consumption of electric energy. The design architecture divides the signal conditioner into three main sections: an analog signal section, a digital module, and a power-management section. The design of the analog signal section does not follow the traditional approach of ensuring reliability through total redundancy of hardware: Instead, following an approach called spare parts tool box, the

  8. Cost-Benefit of Improving the Efficiency of Room Air Conditioners (Inverter and Fixed Speed) in India

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Shah, Nihar; Abhyankar, Nikit; Park, Won Young

    Improving efficiency of air conditioners (ACs) typically involves improving the efficiency of various components such as compressors, heat exchangers, expansion valves, refrigerant and fans. We estimate the incremental cost of improving the efficiency of room ACs based on the cost of improving the efficiency of its key components. Further, we estimate the retail price increase required to cover the cost of efficiency improvement, compare it with electricity bill savings, and calculate the payback period for consumers to recover the additional price of a more efficient AC. We assess several efficiency levels, two of which are summarized below in the report.more » The finding that significant efficiency improvement is cost effective from a consumer perspective is robust over a wide range of assumptions. If we assume a 50% higher incremental price compared to our baseline estimate, the payback period for the efficiency level of 3.5 ISEER is 1.1 years. Given the findings of this study, establishing more stringent minimum efficiency performance criteria (one star level) should be evaluated rigorously considering significant benefits to consumers, energy security and environment.« less

  9. 76 FR 18105 - Energy Conservation Program for Consumer Products: Test Procedures for Residential Central Air...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-01

    ... the low-voltage transformer used when testing coil-only residential central air conditioners and heat... the Low-Voltage Transformer Used When Testing Coil- Only Central Air Conditioners and Heat Pumps and... metric, estimating off-mode energy consumption, and selecting the low- voltage transformer in the test...

  10. Performance Optimization of Alternative Lower Global Warming Potential Refrigerants in Mini-Split Room Air Conditioners

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Shen, Bo; Abdelaziz, Omar; Shrestha, Som S

    Oak Ridge National laboratory (ORNL) recently conducted extensive laboratory, drop-in investigations for lower Global Warming Potential (GWP) refrigerants to replace R-22 and R-410A. ORNL studied propane, DR-3, ARM-20B, N-20B and R-444B as lower GWP refrigerant replacement for R-22 in a mini-split room air conditioner (RAC) originally designed for R-22; and, R-32, DR-55, ARM-71A, and L41-2, in a mini-split RAC designed for R-410A. We obtained laboratory testing results with very good energy balance and nominal measurement uncertainty. Drop-in studies are not enough to judge the overall performance of the alternative refrigerants since their thermodynamic and transport properties might favor different heatmore » exchanger configurations, e.g. cross-flow, counter flow, etc. This study compares optimized performances of individual refrigerants using a physics-based system model tools. The DOE/ORNL Heat Pump Design Model (HPDM) was used to model the mini-split RACs by inputting detailed heat exchangers geometries, compressor displacement and efficiencies as well as other relevant system components. The RAC models were calibrated against the lab data for each individual refrigerant. The calibrated models were then used to conduct a design optimization for the cooling performance by varying the compressor displacement to match the required capacity, and changing the number of circuits, refrigerant flow direction, tube diameters, air flow rates in the condenser and evaporator at 100% and 50% cooling capacities. This paper compares the optimized performance results for all alternative refrigerants and highlights best candidates for R-22 and R-410A replacement.« less

  11. Spectra of conditionalization and typicality in the multiverse

    NASA Astrophysics Data System (ADS)

    Azhar, Feraz

    2016-02-01

    An approach to testing theories describing a multiverse, that has gained interest of late, involves comparing theory-generated probability distributions over observables with their experimentally measured values. It is likely that such distributions, were we indeed able to calculate them unambiguously, will assign low probabilities to any such experimental measurements. An alternative to thereby rejecting these theories, is to conditionalize the distributions involved by restricting attention to domains of the multiverse in which we might arise. In order to elicit a crisp prediction, however, one needs to make a further assumption about how typical we are of the chosen domains. In this paper, we investigate interactions between the spectra of available assumptions regarding both conditionalization and typicality, and draw out the effects of these interactions in a concrete setting; namely, on predictions of the total number of species that contribute significantly to dark matter. In particular, for each conditionalization scheme studied, we analyze how correlations between densities of different dark matter species affect the prediction, and explicate the effects of assumptions regarding typicality. We find that the effects of correlations can depend on the conditionalization scheme, and that in each case atypicality can significantly change the prediction. In doing so, we demonstrate the existence of overlaps in the predictions of different "frameworks" consisting of conjunctions of theory, conditionalization scheme and typicality assumption. This conclusion highlights the acute challenges involved in using such tests to identify a preferred framework that aims to describe our observational situation in a multiverse.

  12. Hybrid respiration-signal conditioner

    NASA Technical Reports Server (NTRS)

    Rinard, G. A.; Steffen, D. A.; Sturm, R. E.

    1979-01-01

    Hybrid impedance-pneumograph and respiration-rate signal conditioner element of hand-held vital signs monitor measures changes in impedance of chest during breathing cycle and generates analog respiration signal as output along with synchronous square wave that can be monitored by breath-rate processor.

  13. Bond strength of resin-modified glass ionomer restorative materials using a no-rinse conditioner.

    PubMed

    Suihkonen, Rian W; Vandewalle, Kraig S; Dossett, Jon M

    2012-01-01

    A paste-paste resin-modified glass ionomer (RMGI) restorative material has been introduced recently with a new conditioner that requires no rinsing. The purpose of this study was to compare the shear bond strength of an encapsulated RMGI (Fuji II LC) and a new paste-paste RMGI (Fuji Filling LC) to dentin conditioned with 20% polyacrylic acid (Cavity Conditioner), a new no-rinse conditioner (Self Conditioner,), or no conditioner. Mounted human third molars were flattened and the dentin surface was conditioned. The RMGI restorative materials were mixed and incrementally inserted into a mold and photocured. The specimens were loaded until failure in a universal testing machine after 24 hours of storage in distilled water. Fuji II LC had significantly greater bond strength to dentin than Fuji Filling LC. The use of Cavity Conditioner or Self Conditioner resulted in bond strengths that were not significantly different from each other; however, both produced greater bond strengths than those in the non-conditioned groups.

  14. The Use of an Air-Natural Gas Flame in Atomic Absorption.

    ERIC Educational Resources Information Center

    Melucci, Robert C.

    1983-01-01

    Points out that excellent results are obtained using an air-natural gas flame in atomic absorption experiments rather than using an air-acetylene flame. Good results are obtained for alkali metals, copper, cadmium, and zinc but not for the alkaline earths since they form refractory oxides. (Author/JN)

  15. Signal conditioner for potentiometer type transducers

    NASA Technical Reports Server (NTRS)

    Armentrout, E. C.; Gross, E.

    1973-01-01

    Low cost method is described for signal conditioning of pot-type transducers utilizing printed circuitry. Conditioner fits into standard rack, accommodates 56 channels, and can be operated by one attendant.

  16. Air Quality Guide for Ozone

    MedlinePlus

    ... outdoors. Note: If you don't have an air conditioner, staying inside with the windows closed may be dangerous in extremely hot weather. In these cases, seek alternative shelter. Key Facts to Know About Ozone: Ozone in the air we breathe can cause serious health problems, including ...

  17. Influences of Different Conditioners on Dehydration Ratio of Activated Sludge

    NASA Astrophysics Data System (ADS)

    Zhuo, Qiongfang; Zheng, Wenli; Yi, Hao; Chen, Sili; Xu, Zhencheng; Jin, Zhong; Lan, Yongzhe; Guo, Qingwei

    2017-11-01

    Excess sludge contains a large quantity of water with water content reaching about 97%-99%. Besides microorganisms and germs, the sludge is of complicated composition, including heavy metals, persistent organic pollutants, PPCPs, endocrine disrupters, etc. It covers a large area with harmfulness, so it needs further treatment. However, due to existence of extracellular polymeric substances in the sludge, the sludge has poor dehydration property, so how to improve dehydration of sludge is a difficult point in water treatment industry. Chemical conditioning—mechanical dehydration method is sludge dehydration technology which has been widely applied in China. Most sludge treatment plants use organic and inorganic conditioners like polyacrylamide (PAM), polyaluminum chloride (PAC) and polymerized ferrous sulfate (PFS), etc. With characteristics of low toxicity and degradation resistance, these conditioners pose potential risks to the environment and they are adverse to follow-up resource utilization. Therefore, influences of 17 conditioners on sludge dehydration ratio were discussed in this paper, expecting to seek for green, environmentally friendly and highly efficient conditioner so as to improve resource utilization ratio of sludge.

  18. Phosphate absorption by air-stressed root systems.

    PubMed

    Dove, L D

    1969-03-01

    Root systems from plants grown in nutrient solution were exposed to air and either transferred to fresh nutrient solution containing (32)P-labeled phosphate or placed in a psychrometer to determine their water potential. The amount of (32)P absorbed by maize and soybean roots in the hour following their exposure to air was proportional to their water potential at the time they were transferred. Some cells, probably located in the stele, were more resistant to moisture stress than others. Absorption of (32)P by all cells was severely inhibited by water potentials below-12 to-15 bars. Nearly normal amounts of the radioisotope and total phosphate were absorbed within 72 hr following root exposure of 4 of 5 species of detopped plants; some phosphorus was lost to the nutrient solution. Uptake of (32)P by passive processes was increased slightly by exposure of roots of intact maize plants to air, but the increase did not compensate for the substantial reduction in actively-absorbed (32)P.

  19. Reducing indoor air pollution by air conditioning is associated with improvements in cardiovascular health among the general population.

    PubMed

    Lin, Lian-Yu; Chuang, Hsiao-Chi; Liu, I-Jung; Chen, Hua-Wei; Chuang, Kai-Jen

    2013-10-01

    Indoor air pollution is associated with cardiovascular effects, however, little is known about the effects of improving indoor air quality on cardiovascular health. The aim of this study was to explore whether improving indoor air quality through air conditioning can improve cardiovascular health in human subjects. We recruited a panel of 300 healthy subjects from Taipei, aged 20 and over, to participate in six home visits each, to measure a variety of cardiovascular endpoints, including high sensitivity-C-reactive protein (hs-CRP), 8-hydroxy-2'-deoxyguanosine (8-OHdG), fibrinogen in plasma and heart rate variability (HRV). Indoor particles and total volatile organic compounds (VOCs) were measured simultaneously at the participant's home during each visit. Three exposure conditions were investigated in this study: participants were requested to keep their windows open during the first two visits, close their windows during the next two visits, and close the windows and turn on their air conditioners during the last two visits. We used linear mixed-effects models to associate the cardiovascular endpoints with individual indoor air pollutants. The results showed that increases in hs-CRP, 8-OHdG and fibrinogen, and decreases in HRV indices were associated with increased levels of indoor particles and total VOCs in single-pollutant and two-pollutant models. The effects of indoor particles and total VOCs on cardiovascular endpoints were greatest during visits with the windows open. During visits with the air conditioners turned on, no significant changes in cardiovascular endpoints were observed. In conclusion, indoor air pollution is associated with inflammation, oxidative stress, blood coagulation and autonomic dysfunction. Reductions in indoor air pollution and subsequent improvements in cardiovascular health can be achieved by closing windows and turning on air conditioners at home. Copyright © 2013 Elsevier B.V. All rights reserved.

  20. During air cool process aerosol absorption detection with photothermal interferometry

    NASA Astrophysics Data System (ADS)

    Li, Baosheng; Xu, Limei; Huang, Junling; Ma, Fei; Wang, Yicheng; Li, Zhengqiang

    2014-11-01

    This paper studies the basic principle of laser photothermal interferometry method of aerosol particles absorption coefficient. The photothermal interferometry method with higher accuracy and lower uncertainty can directly measure the absorption coefficient of atmospheric aerosols and not be affected by scattered light. With Jones matrix expression, the math expression of a special polarization interferometer is described. This paper using folded Jamin interferometer, which overcomes the influence of vibration on measuring system. Interference come from light polarization beam with two orthogonal and then combine to one beam, finally aerosol absorption induced refractive index changes can be gotten with four beam of phase orthogonal light. These kinds of styles really improve the stability of system and resolution of the system. Four-channel detections interact with interference fringes, to reduce the light intensity `zero drift' effect on the system. In the laboratory, this device typical aerosol absorption index, it shows that the result completely agrees with actual value. After heated by laser, cool process of air also show the process of aerosol absorption. This kind of instrument will be used to monitor ambient aerosol absorption and suspended particulate matter chemical component. Keywords: Aerosol absorption coefficient; Photothermal interferometry; Suspended particulate matter.

  1. Study of Flexible Load Dispatch to Improve the Capacity of Wind Power Absorption

    NASA Astrophysics Data System (ADS)

    Yunlei, Yang; Shifeng, Zhang; Xiao, Chang; Da, Lei; Min, Zhang; Jinhao, Wang; Shengwen, Li; Huipeng, Li

    2017-05-01

    The dispatch method which track the trend of load demand by arranging the generation scheme of controllable hydro or thermal units faces great difficulties and challenges. With the increase of renewable energy sources such as wind power and photovoltaic power introduced to grid, system has to arrange much more spinning reserve units to compensate the unbalanced power. How to exploit the peak-shaving potential of flexible load which can be shifted with time or storage energy has become many scholars’ research direction. However, the modelling of different kinds of load and control strategy is considerably difficult, this paper choose the Air Conditioner with compressor which can storage energy in fact to study. The equivalent thermal parameters of Air Conditioner has been established. And with the use of “loop control” strategies, we can predict the regulated power of Air Conditioner. Then we established the Gen-Load optimal scheduling model including flexible load based on traditional optimal scheduling model. At last, an improved IEEE-30 case is used to verify. The result of simulation shows that flexible load can fast-track renewable power changes. More than that, with flexible load and reasonable incentive method to consumers, the operating cost of the system can be greatly cut down.

  2. Reinforced glass-ionomer cements: the influence of conditioners on marginal leakage.

    PubMed

    Yap, A U; Mok, B Y

    1997-06-01

    The purpose of this in vitro study was to evaluate the influence of conditioners on the enamel and dentine margin sealing ability of three different reinforced glass-ionomer cements. Two Class V preparations were made on the buccal and lingual surfaces of 36 freshly extracted molar teeth. Preparations were solely in enamel or dentine/cementum. The teeth were randomly divided into three groups of 12 and restored with either Ketac Silver (KS), Hi-Dense (HD) or Miracle-Mix (MM) with and without (-C) their respective conditioners. All materials were capsulated and were manipulated according to the manufacturers' instructions. The restorations were finished as recommended by the manufacturers and then stored in saline at 37 degrees C for 1 week, polished, thermally stressed, subjected to dye penetration, sectioned and scored. Rankings in the order of decreasing leakage were as follows: enamel margin KS > KS-C > HD-C > HD > MM > MM-C; dentine margin KS > HD-C > KS-C > HD > MM-C > MM. At the enamel margins, only HD showed a significant increase in leakage when conditioner was not used. At the dentine margin, however, KS had significantly more leakage than KS-C and HD-C had significantly more leakage than HD. There was no significant difference in leakage for MM both with and without conditioner. The influence of conditioners on marginal leakage appears to be both product and tissue specific.

  3. Adhesive bonding of super-elastic titanium-nickel alloy castings with a phosphate metal conditioner and an acrylic adhesive.

    PubMed

    Matsumura, H; Tanoue, N; Yanagida, H; Atsuta, M; Koike, M; Yoneyama, T

    2003-06-01

    The purpose of the current study was to evaluate the bonding characteristics of super-elastic titanium-nickel (Ti-Ni) alloy castings. Disk specimens were cast from a Ti-Ni alloy (Ti-50.85Ni mol%) using an arc centrifugal casting machine. High-purity titanium and nickel specimens were also prepared as experimental references. The specimens were air-abraded with alumina, and bonded with an adhesive resin (Super-Bond C & B). A metal conditioner containing a phosphate monomer (Cesead II Opaque Primer) was also used for priming the specimens. Post-thermocycling average bond strengths (MPa) of the primed groups were 41.5 for Ti-Ni, 30.4 for Ti and 19.5 for Ni, whereas those of the unprimed groups were 21.6 for Ti, 19.3 for Ti-Ni and 9.3 for Ni. Application of the phosphate conditioner elevated the bond strengths of all alloy/metals (P < 0.05). X-ray fluorescence analysis revealed that nickel was attached to the debonded resin surface of the resin-to-nickel bonded specimen, indicating that corrosion of high-purity nickel occurred at the resin-nickel interface. Durable bonding to super-elastic Ti-Ni alloy castings can be achieved with a combination of a phosphate metal conditioner and a tri-n-butylborane-initiated adhesive resin.

  4. Flow, stock, and impact assessment of refrigerants in the Japanese household air conditioner sector.

    PubMed

    Xue, Mianqiang; Kojima, Naoya; Machimura, Takashi; Tokai, Akihiro

    2017-05-15

    Refrigerants provide society with great benefits while have the potential to cause adverse effects on the environment and human health. The present study estimated time-dependent flows and stocks and assessed the effects of refrigerants (R-22, R-410a, and R-32) in household air conditioners in Japan. It was found that stock of R-22 and R-410a peaked at 49,147t in 2000 and 55,994t in 2017, respectively. The largest flow of R-22 and R-410a to waste phase occurred at 3417t/yr. in 2005 and 4011t/yr. in 2023, respectively. The total global warming potential (GWP) due to refrigerant emissions increased from 3.6kt CO 2 eq. in 1952 to 6999kt CO 2 eq. in 2019, and then decreased to 5314kt CO 2 eq. in 2030. The ozone depletion potential (ODP) peaked at 141t CFC-11 eq. in 2002. When substituting R-410a for R-22, the ODP decreased 50% while the GDP increased 8%. When substituting R-32 for R-410a, there was no effect on the ODP while the GDP decreased 6%. The human health damage due to the global warming effect of refrigerant emission was much higher than that due to the ozone depleting effect. The refrigerant emission in use and waste management phases dominated the human health damage. The dynamic estimation not only allows us to evaluate the performance of past policies but also supports the future sustainable management associated with the health effects of refrigerants. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. LiCl Dehumidifier LiBr absorption chiller hybrid air conditioning system with energy recovery

    DOEpatents

    Ko, Suk M.

    1980-01-01

    This invention relates to a hybrid air conditioning system that combines a solar powered LiCl dehumidifier with a LiBr absorption chiller. The desiccant dehumidifier removes the latent load by absorbing moisture from the air, and the sensible load is removed by the absorption chiller. The desiccant dehumidifier is coupled to a regenerator and the desiccant in the regenerator is heated by solar heated hot water to drive the moisture therefrom before being fed back to the dehumidifier. The heat of vaporization expended in the desiccant regenerator is recovered and used to partially preheat the driving fluid of the absorption chiller, thus substantially improving the overall COP of the hybrid system.

  6. Measurement of Vehicle Air Conditioning Pull-Down Period

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Thomas, John F.; Huff, Shean P.; Moore, Larry G.

    2016-08-01

    Air conditioner usage was characterized for high heat-load summer conditions during short driving trips using a 2009 Ford Explorer and a 2009 Toyota Corolla. Vehicles were parked in the sun with windows closed to allow the cabin to become hot. Experiments were conducted by entering the instrumented vehicles in this heated condition and driving on-road with the windows up and the air conditioning set to maximum cooling, maximum fan speed and the air flow setting to recirculate cabin air rather than pull in outside humid air. The main purpose was to determine the length of time the air conditioner systemmore » would remain at or very near maximum cooling power under these severe-duty conditions. Because of the variable and somewhat uncontrolled nature of the experiments, they serve only to show that for short vehicle trips, air conditioning can remain near or at full cooling capacity for 10-minutes or significantly longer and the cabin may be uncomfortably warm during much of this time.« less

  7. High-throughput liquid-absorption air-sampling apparatus and methods

    DOEpatents

    Zaromb, Solomon

    2000-01-01

    A portable high-throughput liquid-absorption air sampler [PHTLAAS] has an asymmetric air inlet through which air is drawn upward by a small and light-weight centrifugal fan driven by a direct current motor that can be powered by a battery. The air inlet is so configured as to impart both rotational and downward components of motion to the sampled air near said inlet. The PHTLAAS comprises a glass tube of relatively small size through which air passes at a high rate in a swirling, highly turbulent motion, which facilitates rapid transfer of vapors and particulates to a liquid film covering the inner walls of the tube. The pressure drop through the glass tube is <10 cm of water, usually <5 cm of water. The sampler's collection efficiency is usually >20% for vapors or airborne particulates in the 2-3.mu. range and >50% for particles larger than 4.mu.. In conjunction with various analyzers, the PHTLAAS can serve to monitor a variety of hazardous or illicit airborne substances, such as lead-containing particulates, tritiated water vapor, biological aerosols, or traces of concealed drugs or explosives.

  8. Simulation of a solar-assisted absorption air conditioning system for applications in Puerto Rico

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Khan, A.Y.; Hernandez, H.R.; Gonzalez, J.E.

    1995-11-01

    Regions without conventional fuel sources have felt the need for the development of new technologies for air conditioning applications as cost of electrical energy production has continually risen the cost of air conditioning by conventional means. This paper deals with the simulation of a solar-assisted absorption system for air conditioning application in Puerto Rico. A simple thermodynamic model for the solar assisted absorption system has been developed. A solar energy based thermal storage system along with an auxiliary heater is used to provide the required energy in the generator of this absorption system. Results from a parametric analysis to studymore » the influence of the absorber, generator, condenser and evaporator temperatures, on the COP of the system are presented in this paper. The influence of two different refrigerant/absorbent pairs, water/lithium bromide and water/lithium-chloride have also been studied. A sub-system consisting of an array of flat plate solar collectors along with a hot water storage is modeled and verified with the data from an already existing system operating in Sacramento. Finally, off-design performance of a 35 kW solar-assisted absorption system is simulated to report the auxiliary heating requirement for a typical summer day operation in southern Puerto Rico.« less

  9. Applications of principal component analysis to breath air absorption spectra profiles classification

    NASA Astrophysics Data System (ADS)

    Kistenev, Yu. V.; Shapovalov, A. V.; Borisov, A. V.; Vrazhnov, D. A.; Nikolaev, V. V.; Nikiforova, O. Y.

    2015-12-01

    The results of numerical simulation of application principal component analysis to absorption spectra of breath air of patients with pulmonary diseases are presented. Various methods of experimental data preprocessing are analyzed.

  10. Investigation of Flow Conditioners for Compact Jet Engine Simulator Rig Noise Reduction

    NASA Technical Reports Server (NTRS)

    Doty, Michael J.; Haskin, Henry H.

    2011-01-01

    The design requirements for two new Compact Jet Engine Simulator (CJES) units for upcoming wind tunnel testing lead to the distinct possibility of rig noise contamination. The acoustic and aerodynamic properties of several flow conditioner devices are investigated over a range of operating conditions relevant to the CJES units to mitigate the risk of rig noise. An impinging jet broadband noise source is placed in the upstream plenum of the test facility permitting measurements of not only flow conditioner self-noise, but also noise attenuation characteristics. Several perforated plate and honeycomb samples of high porosity show minimal self-noise but also minimal attenuation capability. Conversely, low porosity perforated plate and sintered wire mesh conditioners exhibit noticeable attenuation but also unacceptable self-noise. One fine wire mesh sample (DP450661) shows minimal selfnoise and reasonable attenuation, particularly when combined in series with a 15.6 percent open area (POA) perforated plate upstream. This configuration is the preferred flow conditioner system for the CJES, providing up to 20 dB of broadband attenuation capability with minimal self-noise.

  11. Air Conditioner Charging. Automotive Mechanics. Air Conditioning. Instructor's Guide [and] Student Guide.

    ERIC Educational Resources Information Center

    Spignesi, B.

    This instructional package, one in a series of individualized instructional units on automobile air conditioning, consists of a student guide and an instructor guide dealing with air conditioning charging. Covered in the module are checking the air conditioning system for leaks, checking and adding refrigerant oil as needed, evacuating the system,…

  12. Future emissions and atmospheric fate of HFC-1234yf from mobile air conditioners in Europe.

    PubMed

    Henne, Stephan; Shallcross, Dudley E; Reimann, Stefan; Xiao, Ping; Brunner, Dominik; O'Doherty, Simon; Buchmann, Brigitte

    2012-02-07

    HFC-1234yf (2,3,3,3-tetrafluoropropene) is under discussion for replacing HFC-134a (1,1,1,2-tetrafluoroethane) as a cooling agent in mobile air conditioners (MACs) in the European vehicle fleet. Some HFC-1234yf will be released into the atmosphere, where it is almost completely transformed to the persistent trifluoroacetic acid (TFA). Future emissions of HFC-1234yf after a complete conversion of the European vehicle fleet were assessed. Taking current day leakage rates and predicted vehicle numbers for the year 2020 into account, European total HFC-1234yf emissions from MACs were predicted to range between 11.0 and 19.2 Gg yr(-1). Resulting TFA deposition rates and rainwater concentrations over Europe were assessed with two Lagrangian chemistry transport models. Mean European summer-time TFA mixing ratios of about 0.15 ppt (high emission scenario) will surpass previously measured levels in background air in Germany and Switzerland by more than a factor of 10. Mean deposition rates (wet + dry) of TFA were estimated to be 0.65-0.76 kg km(-2) yr(-1), with a maxium of ∼2.0 kg km(-2) yr(-1) occurring in Northern Italy. About 30-40% of the European HFC-1234yf emissions were deposited as TFA within Europe, while the remaining fraction was exported toward the Atlantic Ocean, Central Asia, Northern, and Tropical Africa. Largest annual mean TFA concentrations in rainwater were simulated over the Mediterranean and Northern Africa, reaching up to 2500 ng L(-1), while maxima over the continent of about 2000 ng L(-1) occurred in the Czech Republic and Southern Germany. These highest annual mean concentrations are at least 60 times lower than previously determined to be a safe level for the most sensitive aquatic life-forms. Rainwater concentrations during individual rain events would still be 1 order of magnitude lower than the no effect level. To verify these results future occasional sampling of TFA in the atmospheric environment should be considered. If future HFC-1234yf

  13. Air Conditioner Ready to Change Industry - Continuum Magazine | NREL

    Science.gov Websites

    create very dry air, ideal for cooling with evaporative techniques. Desiccants, which can be liquids or into an innovative "cooling core." This would marry the desiccants' capacity to create dry air using heat and evaporative coolers' capability to turn dry air into cold air. If it worked, it

  14. Alternate working fluids for solar air conditioning applications

    NASA Technical Reports Server (NTRS)

    Evans, R. D.; Beck, J. K.

    1978-01-01

    An experimental investigation of sixteen different refrigerant-absorbent fluid pairs has been carried out in order to determine their suitability as the working fluid in a solar-powered absorption cycle air conditioner. The criteria used in the initial selection of a refrigerant-absorbent pair included: high affinity (large negative deviation from Raoult's Law), high solubility, low specific heat, low viscosity, stability, corrosive properties, safety, and cost. For practical solar considerations of a fluid pair, refrigerants were selected with low boiling points whereas absorbent fluids were selected with a boiling point considerably above that of the refrigerant. Additional restrictions are determined by the operating temperatures of the absorber and the generator; these temperatures were specified as 100 F (39 C) and 170 F (77 C). Data are presented for a few selected pressures at the specified absorber and generator temperatures.

  15. Factors influencing on the bioaccessibility of polybrominated diphenyl ethers in size-specific dust from air conditioner filters.

    PubMed

    Yu, Yingxin; Yang, Dan; Wang, Xinxin; Huang, Ningbao; Zhang, Xinyu; Zhang, Dongping; Fu, Jiamo

    2013-11-01

    Size-specific concentrations and bioaccessibility of polybrominated diphenyl ethers (PBDEs) in dust from air conditioner filters were measured, and the factors influencing the PBDE bioaccessibility were determined. Generally, the PBDE concentrations increased with decreasing dust particle size, and BDE209 (deca-BDE) was generally the predominant congener. The bioaccessibility ranged from 20.3% to 50.8% for tri- to hepta-BDEs, and from 5.1% to 13.9% for BDE209 in dust fractions of varied particle size. The bioaccessibility of most PBDE congeners decreased with increasing dust particle size. The way of being of PBDE (adsorbed to dust surface or incorporated into polymers) in dust significantly influenced the bioaccessibility. There was a significant negative correlation between the tri- to hepta-BDE bioaccessibility and organic matter (OM) contents in dust. Furthermore, tri- to hepta-BDE bioaccessibility increased with increasing polarity of OMs, while with decreasing aromaticity of OMs. The tri- to hepta-BDE bioaccessibility significantly positively correlated with the surface areas and pore volumes of dust. Using multiple linear regression analysis, it was found that the OM contents and pore volumes of dust were the most important factors to influence the tri- to hepta-BDE bioaccessibility and they could be used to estimate the bioaccessibility of tri- to hepta-BDEs according to the following equation: bioaccessibility (%)=45.05-0.49 × OM%+1.79 × pore volume. However, BDE209 bioaccessibility did not correlate to any of these factors. Copyright © 2013 Elsevier Ltd. All rights reserved.

  16. Occurrence of polybrominated diphenyl ethers in indoor air and dust in Hangzhou, China: Level, role of electric appliances, and human exposure.

    PubMed

    Sun, Jianqiang; Wang, Qianwen; Zhuang, Shulin; Zhang, Anping

    2016-11-01

    This study investigated the occurrence of 8 polybrominated diphenyl ether (PBDE) congeners from homes (n = 20), offices (n = 20), air conditioners (n = 6), and computers (n = 6). High detection frequencies for most of the congeners were observed, indicating continued widespread use of Penta-, Octa- and Deca-BDE mixtures. The median concentrations of ∑PBDEs were 119 and 194 pg m -3 for home air and office air, respectively. Regarding dust, the median concentrations of ∑PBDEs were 239 and 437 ng g -1 for home and office dust, respectively. The ratios of the median concentrations of BDE-209 to ∑PBDEs were approximately 0.95 and 0.87 for home dust and office dust, respectively. The median concentrations of ∑PBDEs were 359 ng g -1 and 350 ng g -1 for dust on air conditioner filters and the back cabinet of the computer, respectively. The ratios of the median concentrations of BDE-209 to ∑PBDEs were approximately 0.58 and 0.46 for air conditioner and computer samples. Running air conditioners contributed to ΣPBDEs in office air through direct and indirect pathways. The daily intake of PBDEs was estimated to be 2630 pg (kg bw) -1 day -1 for toddlers in homes and 319 pg (kg bw) -1 day -1 for adults in homes and offices. Copyright © 2016 Elsevier Ltd. All rights reserved.

  17. Improve the material absorption of light and enhance the laser tube bending process utilizing laser softening heat treatment

    NASA Astrophysics Data System (ADS)

    Imhan, Khalil Ibraheem; Baharudin, B. T. H. T.; Zakaria, Azmi; Ismail, Mohd Idris Shah B.; Alsabti, Naseer Mahdi Hadi; Ahmad, Ahmad Kamal

    2018-02-01

    Laser forming is a flexible control process that has a wide spectrum of applications; particularly, laser tube bending. It offers the perfect solution for many industrial fields, such as aerospace, engines, heat exchangers, and air conditioners. A high power pulsed Nd-YAG laser with a maximum average power of 300 W emitting at 1064 nm and fiber-coupled is used to irradiate stainless steel 304 (SS304) tubes of 12.7 mm diameter, 0.6 mm thickness and 70 mm length. Moreover, a motorized rotation stage with a computer controller is employed to hold and rotate the tube. In this paper, an experimental investigation is carried out to improve the laser tube bending process by enhancing the absorption coefficient of the material and the mechanical formability using laser softening heat treatment. The material surface is coated with an oxidization layer; hence, the material absorption of laser light is increased and the temperature rapidly rises. The processing speed is enhanced and the output bending angle is increased to 1.9° with an increment of 70% after the laser softening heat treatment.

  18. 21 CFR 882.1845 - Physiological signal conditioner.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Physiological signal conditioner. 882.1845 Section 882.1845 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES NEUROLOGICAL DEVICES Neurological Diagnostic Devices § 882.1845 Physiological...

  19. 21 CFR 882.1845 - Physiological signal conditioner.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Physiological signal conditioner. 882.1845 Section 882.1845 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES NEUROLOGICAL DEVICES Neurological Diagnostic Devices § 882.1845 Physiological...

  20. Low-noise pulse conditioner

    DOEpatents

    Bird, David A.

    1983-01-01

    A low-noise pulse conditioner is provided for driving electronic digital processing circuitry directly from differentially induced input pulses. The circuit uses a unique differential-to-peak detector circuit to generate a dynamic reference signal proportional to the input peak voltage. The input pulses are compared with the reference signal in an input network which operates in full differential mode with only a passive input filter. This reduces the introduction of circuit-induced noise, or jitter, generated in ground referenced input elements normally used in pulse conditioning circuits, especially speed transducer processing circuits.

  1. Design and evaluation of an inlet conditioner to dry particles for real-time particle sizers.

    PubMed

    Peters, Thomas M; Riss, Adam L; Holm, Ricky L; Singh, Manisha; Vanderpool, Robert W

    2008-04-01

    Real-time particle sizers provide rapid information about atmospheric particles, particularly peak exposures, which may be important in the development of adverse health outcomes. However, these instruments are subject to erroneous readings in high-humidity environments when compared with measurements from filter-based, federal reference method (FRM) samplers. Laboratory tests were conducted to evaluate the ability of three inlet conditioners to dry aerosol prior to entering a real-time particle sizer for measuring coarse aerosols (Model 3321 Aerodynamic Particle Sizer, APS) under simulated highly humid conditions. Two 30 day field studies in Birmingham, AL, USA were conducted to compare the response of two APSs operated with and without an inlet conditioner to that measured with FRM samplers. In field studies, the correlation of PM(10-2.5) derived from the APS and that measured with the FRM was substantially stronger with an inlet conditioner applied (r2 ranged from 0.91 to 0.99) than with no conditioner (r2 = 0.61). Laboratory experiments confirmed the ability of the heater and desiccant conditioner to remove particle-borne moisture. In field tests, water was found associated with particles across the sizing range of the APS (0.5 microm to 20 microm) when relative humidity was high in Birmingham. Certain types of inlet conditioners may substantially improve the correlation between particulate mass concentration derived from real-time particle sizers and filter-based samplers in humid conditions.

  2. On the evaluation of air mass factors for atmospheric near-ultraviolet and visible absorption spectroscopy

    NASA Technical Reports Server (NTRS)

    Perliski, Lori M.; Solomon, Susan

    1993-01-01

    The interpretation of UV-visible twilight absorption measurements of atmospheric chemical constituents is dependent on how well the optical path, or air mass factor, of light collected by the spectrometer is understood. A simple single scattering model and a Monte Carlo radiative transfer scheme have been developed to study the effects of multiple scattering, aerosol scattering, surface albedo and refraction on air mass factors for scattered light observations. At fairly short visible wavelengths (less than about 450 nm), stratospheric air mass factors are found to be relatively insensitive to multiple scattering, surface albedo and refraction, as well as aerosol scattering by background aerosols. Longer wavelengths display greater sensitivity to refraction and aerosol scattering. Tropospheric air mass factors are found to be highly dependent on aerosol scattering, surface albedo and, at long visible wavelengths (about 650 nm), refraction. Absorption measurements of NO2 and O4 are shown to support these conclusions.

  3. In vitro antimicrobial effect of the tissue conditioner containing silver nanoparticles

    PubMed Central

    2011-01-01

    PURPOSE The aim of this study was to identify in vitro antimicrobial activity of the tissue conditioner containing silver nanoparticles on microbial strains, Staphylococcus aureus, Streptococcus mutans and Candida albicans. MATERIALS AND METHODS Experimental disc samples (20.0×3.0 mm) of tissue conditioner (GC Soft-Liner, GC cooperation, Tokyo, Japan) containing 0.1 - 3.0% silver nanoparticles (0%: control) were fabricated. Samples were placed on separate culture plate dish and microbial suspensions (100 µL) of tested strains were inoculated then incubated at 37℃. Microbial growth was verified at 24 hrs and 72 hrs and the antimicrobial effects of samples were evaluated as a percentage of viable cells in withdrawn suspension (100 µL). Data were recorded as the mean of three colony forming unit (CFU) numerations and the borderline of the antimicrobial effect was determined at 0.1% viable cells. RESULTS A 0.1% silver nanoparticles combined to tissue conditioner displayed minimal bactericidal effect against Staphylococcus aureus and Streptococcus mutans strains, a 0.5% for fungal strain. Control group did not show any microbial inhibitory effect and there were no statistical difference between 24 hrs and extended 72 hrs incubation time (P > .05). CONCLUSION Within the limitation of this in vitro study, the results suggest that the tissue conditioner containing silver nanoparticles could be an antimicrobial dental material in denture plaque control. Further mechanical stability and toxicity studies are still required. PMID:21503189

  4. Active Sensing Air Pressure Using Differential Absorption Barometric Radar

    NASA Astrophysics Data System (ADS)

    Lin, B.

    2016-12-01

    Tropical storms and other severe weathers cause huge life losses and property damages and have major impacts on public safety and national security. Their observations and predictions need to be significantly improved. This effort tries to develop a feasible active microwave approach that measures surface air pressure, especially over open seas, from space using a Differential-absorption BArometric Radar (DiBAR) operating at 50-55 GHz O2 absorption band in order to constrain assimilated dynamic fields of numerical weather Prediction (NWP) models close to actual conditions. Air pressure is the most important variable that drives atmospheric dynamics, and currently can only be measured by limited in-situ observations over oceans. Even over land there is no uniform coverage of surface air pressure measurements. Analyses show that with the proposed space radar the errors in instantaneous (averaged) pressure estimates can be as low as 4mb ( 1mb) under all weather conditions. NASA Langley research team has made substantial progresses in advancing the DiBAR concept. The feasibility assessment clearly shows the potential of surface barometry using existing radar technologies. The team has also developed a DiBAR system design, fabricated a Prototype-DiBAR (P-DiBAR) for proof-of-concept, conducted laboratory, ground and airborne P-DiBAR tests. The flight test results are consistent with the instrumentation goals. The precision and accuracy of radar surface pressure measurements are within the range of the theoretical analysis of the DiBAR concept. Observational system simulation experiments for space DiBAR performance based on the existing DiBAR technology and capability show substantial improvements in tropical storm predictions, not only for the hurricane track and position but also for the hurricane intensity. DiBAR measurements will provide us an unprecedented level of the prediction and knowledge on global extreme weather and climate conditions.

  5. Air Conditioning. Trade and Industrial Education Trade Preparatory Training Guide.

    ERIC Educational Resources Information Center

    Nebraska State Dept. of Education, Lincoln. Div. of Vocational Education.

    One of a series of curriculum guides prepared for the building occupations cluster of the construction/fabrication occupational group, this guide identifies the essentials of the air conditioning trade as recommended by the successful air conditioner. An instructional program based upon the implementation of the guide is expected to prepare a…

  6. Concentrations of polybrominated diphenyl ethers (PBDEs) in central air-conditioner filter dust and relevance of non-dietary exposure in occupational indoor environments in Greece.

    PubMed

    Besis, Athanasios; Katsoyiannis, Athanasios; Botsaropoulou, Elisavet; Samara, Constantini

    2014-05-01

    Polybrominated Diphenyl Ethers (PBDEs) are ubiquitous in the indoor environment owing to their use in consumer products and various studies around the world have found higher concentrations indoors than outdoors. Central air conditioner (A/C) systems have been widely used in many workplaces, therefore, studying of PBDEs in central A/C filter dust is useful to better understand the occurrences and health implications of PBDEs in indoor environments. The present study examined the occurrence of PBDEs in central A/C filter dust collected from various workplaces (n = 20) in Thessaloniki, Greece. The sum concentrations of 21 target congeners (∑21PBDE) in A/C dust ranged between 84 and 4062 ng g(-1) with a median value of 1092 ng g(-1), while BDE-209 was found to be the most abundant BDE congener. The daily intake via dust ingestion of PBDEs estimated for the employees of the occupational settings ranged from 3 to 45 ng day(-1) (median 12 ng day(-1)). Copyright © 2014 Elsevier Ltd. All rights reserved.

  7. Detection of Ozone and Nitric Oxide in Decomposition Products of Air-Insulated Switchgear Using Ultraviolet Differential Optical Absorption Spectroscopy (UV-DOAS).

    PubMed

    Li, Yalong; Zhang, Xiaoxing; Li, Xin; Cui, Zhaolun; Xiao, Hai

    2018-01-01

    Air-insulated switchgear cabinets play a role in the protection and control of the modern power grid, and partial discharge (PD) switchgear is a long-term process in the non-normal operation of one of the situations; thus, condition monitoring of the switchgear is important. The air-insulated switchgear during PD enables the decomposition of air components, namely, O 3 and NO. A set of experimental platforms was designed on the basis of the principle of ultraviolet differential optical absorption spectroscopy (UV-DOAS) to detect O 3 and NO concentrations in air-insulated switchgear. Differential absorption algorithm and wavelet transform were used to extract effective absorption spectra; a linear relationship between O 3 and NO concentrations and absorption spectrum data were established. O 3 detection linearity was up to 0.9992 and the detection limit was at 3.76 ppm. NO detection linearity was up to 0.9990 and the detection limit was at 0.64 ppm. Results indicate that detection platform is suitable for detecting trace O 3 and NO gases produced by PD of the air-insulated switchgear.

  8. Laser absorption of nitric oxide for thermometry in high-enthalpy air

    NASA Astrophysics Data System (ADS)

    Spearrin, R. M.; Schultz, I. A.; Jeffries, J. B.; Hanson, R. K.

    2014-12-01

    The design and demonstration of a laser absorption sensor for thermometry in high-enthalpy air is presented. The sensor exploits the highly temperature-sensitive and largely pressure-independent concentration of nitric oxide in air at chemical equilibrium. Temperature is thus inferred from an in situ measurement of nascent nitric oxide. The strategy is developed by utilizing a quantum cascade laser source for access to the strong fundamental absorption band in the mid-infrared spectrum of nitric oxide. Room temperature measurements in a high-pressure static cell validate the suitability of the Voigt lineshape model to the nitric oxide spectra at high gas densities. Shock-tube experiments enable calibration of a collision-broadening model for temperatures between 1200-3000 K. Finally, sensor performance is demonstrated in a high-pressure shock tube by measuring temperature behind reflected shock waves for both fixed-chemistry experiments where nitric oxide is seeded, and for experiments involving nitric oxide formation in shock-heated mixtures of N2 and O2. Results show excellent performance of the sensor across a wide range of operating conditions from 1100-2950 K and at pressures up to 140 atm.

  9. 2-in-1 shampoo technology: state-of-the-art shampoo and conditioner in one.

    PubMed

    Rushton, H; Gummer, C L; Flasch, H

    1994-01-01

    Consumers have expressed a need for cleaning and conditioning in one step. Conventional shampoo technology using anionic surfactants and cationic conditioners results in charge interaction and complexing of the ingredients. Neither shampoo nor conditioners achieves the desired result. The successful solution was to incorporate charge neutral dimethicone conditioning ingredients, suspended as microfine droplets within complex crystal lattices, into anionic surfactant shampoo technology. The same solution has also been applied to amphoteric surfactant systems. This provides complete cleaning, and hair conditioning fully equal to separate conditioners without the problems of sebum interactions and conditioner build-up. This was achieved by keeping the dimethicone in suspension throughout the shampoo process. During rinsing, excess water breaks the crystalline lattice and allows deposition of the dimethicone droplets onto the hair. Full cleaning and conditioning are, therefore, achieved in one application. Dimethicone build-up is not encountered as subsequent washes first remove soil and previously deposited dimethicone. Neither do neutral dimethicones show any reactions with sebum. The development of effective 2-in-1 technology has had a major impact on shampoo technology and consumer habits and practices. This has significantly changed the way consumers care for their hair.

  10. Characteristics of indoor radon and its progeny in a Japanese dwelling while using air appliances.

    PubMed

    Pornnumpa, C; Tokonami, S; Sorimachi, A; Kranrod, C

    2015-11-01

    Characteristics of radon and its progeny were investigated in different air conditions by turning four types of indoor air appliances on and off in a two-story concrete Japanese dwelling. The four appliances were air conditioner, air cleaner, gas heater and cooker hood. The measurements were done using two devices: (1) a Si-based semiconductor detector for continuous measurement of indoor radon concentration and (2) a ZnS(Ag) scintillation counting system for equilibrium-equivalent radon concentration. Throughout the entire experiment, the cooker hood was the most effective in decreasing indoor radon concentration over a long period of time and the less effective was the air conditioner, while the air cleaner and gas heater did not affect the concentration of radon. However, the results measured in each air condition will differ according to the lifestyles and activities of the inhabitants. In this study, indoor radon and its progeny in a Japanese dwelling will be characterised by the different air conditions. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  11. Absorption spectrum and absorption cross sections of the 2ν1 band of HO2 between 20 and 760 Torr air in the range 6636 and 6639 cm-1

    NASA Astrophysics Data System (ADS)

    Assaf, Emmanuel; Liu, Lu; Schoemaecker, Coralie; Fittschen, Christa

    2018-05-01

    The absorption spectrum of HO2 radicals has been measured in the range 6636-6639 cm-1 at several pressures between 20 and 760 Torr of air. Absolute absorption cross sections of the strongest line at around 6638.2 cm-1 have been determined from kinetic measurements, taking advantage of the well known rate constant of the self-reaction. Peak absorption cross sections of 22.6, 19.5, 14.4, 7.88, 5.12 and 3.23 × 10-20 cm2 were obtained at 20, 50, 100, 200, 400 and 760 Torr, respectively. By fitting these data, an empirical expression has been obtained for the absorption cross section of HO2 in the range 20-760 Torr air: σ6638.2cm-1 = 1.18 × 10-20 + (2.64 × 10-19 × (1-exp (-63.1/p (Torr))) cm2.

  12. Cooling system for radiator and condenser of vehicles with an air conditioner and method of operating the same

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Shimada, Y.; Obata, Y.; Takeoka, T.

    1987-04-21

    A cooling system is described for radiator and condenser of vehicles with an air conditioner having a first blower and a second blower for cooling the radiator and the condenser so as to cool the engine cooling water and so as to condense the coolant, and a cooling cycle operation switch which comprises: (a) engine cooling water temperature switch (SW1) connected between a power supply and the first blower and turned on and off in accordance with high and low temperature conditions of the engine cooling water; (b) relay switching means for controlling the first and second blowers in accordancemore » with the on-off conditions of the cooling cycle operation switch; and (c) a control circuit having an on-off switch and a solenoid and connected between the relay switching means and either the first blower or the second blower, the solenoid of the control circuit being connected to switches (SW3, SW4 and SW5) for electrical equipment such as headlights, wipers; whereby, when any one of the switches for the electrical equipment of the vehicle is turned off, the first and second blowers are operated at normal speed through the relay switching means and the control circuit, upon the operation of the cooling cycle operation switch, while when any one of the switches for the electrical equipment is turned on, the first blower is on-off controlled through the engine cooling water temperature switch (SW1) and the second blower remains operated through the relay switching means.« less

  13. Solar-powered compression-enhanced ejector air conditioner

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sokolov, M.; Hershgal, D.

    1993-09-01

    This article is an extension of an earlier investigation into the possibility of adaptation of the ejector refrigeration cycle to solar air-conditioning. In a previous work the ejector cycle has been proven a viable option only for a limited number of cases. These include systems with combined (heating, cooling, and hot water supply) loads where means for obtaining low condensing temperature are available. The purpose of this work is to extend the applicability of such systems by enhancing their efficiency and thereby improving their economical attractiveness. This is done by introducing the compression enhanced ejector system in which mechanical (rathermore » than thermal) energy is used to boost the pressure of the secondary stream into the ejector, Such a boost improves the performance of the whole system. Similar to the conventional ejector, the compression-enhanced ejector system utilizes practically the same hardware for solar heating during the winter and for solar cooling during the summer. Thus, it is capable of providing a year-round space air-conditioning. Optimization of the best combination in which the solar and refrigeration systems combine through the vapor generator working temperature is also presented.« less

  14. You Can Help Keep the Air Cleaner -- Every Day

    MedlinePlus

    ... to be high: Conserve electricity and set your air conditioner at a higher temperature. Choose a cleaner commute—share a ride to work or use public transportation. Bicycle or walk to errands when ... quality is forecast. Pesticides Days when particle pollution ...

  15. COMPOSITION CHANGES IN REFRIGERANT BLENDS FOR AUTOMOTIVE AIR CONDITIONING

    EPA Science Inventory

    Three refrigerant blends used to replace CFC-12 in automotive air conditioners were evaluated for composition changes due to typical servicing and leakage. When recommended service procedures were followed, changes in blend compositions were relatively small. Small changes in b...

  16. Low-noise pulse conditioner

    DOEpatents

    Bird, D.A.

    1981-06-16

    A low-noise pulse conditioner is provided for driving electronic digital processing circuitry directly from differentially induced input pulses. The circuit uses a unique differential-to-peak detector circuit to generate a dynamic reference signal proportional to the input peak voltage. The input pulses are compared with the reference signal in an input network which operates in full differential mode with only a passive input filter. This reduces the introduction of circuit-induced noise, or jitter, generated in ground referenced input elements normally used in pulse conditioning circuits, especially speed transducer processing circuits. This circuit may be used for conditioning the sensor signal from the Fidler coil in a gas centrifuge for separation of isotopic gaseous mixtures.

  17. Shampoo and Conditioners: What a Dermatologist Should Know?

    PubMed Central

    D'Souza, Paschal; Rathi, Sanjay K

    2015-01-01

    Dermatologists many a times encounter questions from patients and even colleagues asking about how to keep their hair looking clean, healthy and beautiful. Therefore, familiarity and a basic knowledge of the available hair care products will help them to guide their patients properly. A shampoo not only provides the cleaning of the scalp skin and hair as its primary function, but in addition also serves to condition and beautify hair and acts as an adjunct in the management of various scalp disorders. To achieve this, various ingredients in the correct proportion are mixed to provide a shampoo which is suitable for individuals having different hair types and hair need. Among the ingredients that go into the making of a shampoo are detergents, conditioners, thickeners, sequestering agents, pH adjusters, preservatives and specialty additives. Hair conditioners are designed to improve hair manageability, decrease hair static electricity and add luster. They are used in several ways depending upon the state of hair and requirement of the individual. This article attempts to put forward the basic and practical aspects regarding use of these products. PMID:26120149

  18. Shampoo and Conditioners: What a Dermatologist Should Know?

    PubMed

    D'Souza, Paschal; Rathi, Sanjay K

    2015-01-01

    Dermatologists many a times encounter questions from patients and even colleagues asking about how to keep their hair looking clean, healthy and beautiful. Therefore, familiarity and a basic knowledge of the available hair care products will help them to guide their patients properly. A shampoo not only provides the cleaning of the scalp skin and hair as its primary function, but in addition also serves to condition and beautify hair and acts as an adjunct in the management of various scalp disorders. To achieve this, various ingredients in the correct proportion are mixed to provide a shampoo which is suitable for individuals having different hair types and hair need. Among the ingredients that go into the making of a shampoo are detergents, conditioners, thickeners, sequestering agents, pH adjusters, preservatives and specialty additives. Hair conditioners are designed to improve hair manageability, decrease hair static electricity and add luster. They are used in several ways depending upon the state of hair and requirement of the individual. This article attempts to put forward the basic and practical aspects regarding use of these products.

  19. Effect of Addition of Antifungal Agents on Physical and Biological Properties of a Tissue Conditioner: An In-Vitro Study.

    PubMed

    Rawat, Pragati; Agarwal, Swatantra; Tripathi, Siddhi

    2017-09-01

    Purpose: Tissue conditioners are used for healing of abused oral tissues. They may harbour microorganisms causing oral diseases such as candidiasis compromising the health of the patient. Also, addition of antifungal agents into tissue conditioner may alter its properties. This study compares the anti-fungal property and mechanical properties of tissue conditioner containing different antifungal agents. Methods: Three antifungal agents, one synthetic - fluconazole, and two natural - oregano oil and virgin coconut oil were added into the tissue conditioner (Viscogel) in different concentrations. The antifungal property, tensile bond strength and viscoelasticity of Viscogel containing these antifungal agents were assessed after 24 hours, three days and seven days. Results: While, the highest antifungal activity was shown by Viscogel containing fluconazole, the maximum tensile bond strength was found to be of Viscogel alone (control). Although Viscogel alone and in combination of fluconazole showed deterioration in viscoelasticity, Viscogel in combination of natural agents showed no significant changes over the period of seven days. Conclusion: Incorporation of the natural agents in the tissue conditioner can be used as an effective alternative to systemic or topical synthetic antifungal agents.

  20. Laser-induced micro-plasmas in air for incoherent broadband cavity-enhanced absorption spectroscopy

    NASA Astrophysics Data System (ADS)

    Ruth, Albert; Dixneuf, Sophie; Orphal, Johannes

    2016-04-01

    Incoherent broadband cavity-enhanced absorption spectroscopy (IBBCEAS) is an experimentally straightforward absorption method where the intensity of light transmitted by an optically stable (high finesse) cavity is measured. The technique is realized using broadband incoherent sources of radiation and therefore the amount of light transmitted by a cavity consisting of high reflectance mirrors (typically R > 99.9%) can be low. In order to find an alternative to having an incoherent light source outside the cavity, an experiment was devised, where a laser-induced plasma in ambient air was generated inside a quasi-confocal cavity by a high-power femtosecond laser. The emission from the laser-induced plasma was utilized as pulsed broadband light source. The time-dependent spectra of the light leaking from the cavity were compared with those of the laser-induced plasma emission without the cavity. It was found that the light emission was sustained by the cavity despite the initially large optical losses caused by the laser-induced plasma in the cavity. The light sustained by the cavity was used to measure part of the S1 ← S0 absorption spectrum of gaseous azulene at its vapour pressure at room temperature in ambient air, as well as the strongly forbidden γ-band in molecular oxygen (b1Σ(2,0) ← X3Σ(0,0)).

  1. Sound absorption and transmission through flexible micro-perforated panels backed by an air layer and a thin plate.

    PubMed

    Bravo, Teresa; Maury, Cédric; Pinhède, Cédric

    2012-05-01

    This paper describes theoretical and experimental investigations into the sound absorption and transmission properties of micro-perforated panels (MPP) backed by an air cavity and a thin plate. A fully coupled modal approach is proposed to calculate the absorption coefficient and the transmission loss of finite-sized micro-perforated panels-cavity-panel (MPPCP) partitions with conservative boundary conditions. It is validated against infinite partition models and experimental data. A practical methodology is proposed using collocated pressure-velocity sensors to evaluate in an anechoic environment the transmission and absorption properties of conventional MPPCPs. Results show under which conditions edge scattering effects should be accounted for at low frequencies. Coupled mode analysis is also performed and analytical approximations are derived from the resonance frequencies and mode shapes of a flexible MPPCP. It is found that the Helmholtz-type resonance frequency is deduced from the one associated to the rigidly backed MPPCP absorber shifted up by the mass-air mass resonance of the flexible non-perforated double-panel. Moreover, it is shown analytically and experimentally that the absorption mechanisms at the resonances are governed by a large air-frame relative velocity over the MPP surface, with either in-phase or out-of-phase relationships, depending on the MPPCP parameters.

  2. Small photovoltaic setup for the air conditioning system

    NASA Astrophysics Data System (ADS)

    Masiukiewicz, Maciej

    2017-10-01

    The increasing interest in air conditioning systems for residential applications in Poland will certainly increase the demand for electricity during the summer period. Due to this fact a growing interest in solutions that help to lower the electricity consumption in this sector is observed. The problem of increased energy demand for air conditioning purposes can be solved by transfer the consumption of electricity from the grid system to renewable energy sources (RES). The greatest demand for cooling occurs during the biggest sunlight. This is the basis for the analysis of technical power system based on photovoltaic cells (PV) to power the split type air conditioner. The object of the study was the commercial residential airconditioning inverter units with a capacity of 2.5kW. A network electricity production system for their own use with the possibility of buffering energy in batteries (OFF-GRID system). Currently, on the Polish market, there are no developed complete solutions dedicated to air conditioning systems based on PV. In Poland, solar energy is mainly used for heat production in solar collectors. The proposed solution will help to increase the popularity of PV systems in the Polish market as an alternative to other RES. The basic conclusion is that the amount of PV energy generated was sufficient to cover the daily energy requirement of the air conditioner.

  3. 21 CFR 870.2050 - Biopotential amplifier and signal conditioner.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Biopotential amplifier and signal conditioner. 870.2050 Section 870.2050 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CARDIOVASCULAR DEVICES Cardiovascular Monitoring Devices § 870.2050...

  4. 21 CFR 870.2060 - Transducer signal amplifier and conditioner.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Transducer signal amplifier and conditioner. 870.2060 Section 870.2060 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CARDIOVASCULAR DEVICES Cardiovascular Monitoring Devices § 870.2060...

  5. 21 CFR 870.2060 - Transducer signal amplifier and conditioner.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Transducer signal amplifier and conditioner. 870.2060 Section 870.2060 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CARDIOVASCULAR DEVICES Cardiovascular Monitoring Devices § 870.2060...

  6. 21 CFR 870.2060 - Transducer signal amplifier and conditioner.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Transducer signal amplifier and conditioner. 870.2060 Section 870.2060 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CARDIOVASCULAR DEVICES Cardiovascular Monitoring Devices § 870.2060...

  7. 21 CFR 870.2060 - Transducer signal amplifier and conditioner.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Transducer signal amplifier and conditioner. 870.2060 Section 870.2060 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CARDIOVASCULAR DEVICES Cardiovascular Monitoring Devices § 870.2060...

  8. 21 CFR 870.2050 - Biopotential amplifier and signal conditioner.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Biopotential amplifier and signal conditioner. 870.2050 Section 870.2050 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CARDIOVASCULAR DEVICES Cardiovascular Monitoring Devices § 870.2050...

  9. 21 CFR 870.2060 - Transducer signal amplifier and conditioner.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Transducer signal amplifier and conditioner. 870.2060 Section 870.2060 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES CARDIOVASCULAR DEVICES Cardiovascular Monitoring Devices § 870.2060...

  10. Attenuator And Conditioner

    DOEpatents

    Anderson, Gene R.; Armendariz, Marcelino G.; Carson, Richard F.; Bryan, Robert P.; Duckett, III, Edwin B.; Kemme, Shanalyn Adair; McCormick, Frederick B.; Peterson, David W.

    2006-04-04

    An apparatus and method of attenuating and/or conditioning optical energy for an optical transmitter, receiver or transceiver module is disclosed. An apparatus for attenuating the optical output of an optoelectronic connector including: a mounting surface; an array of optoelectronic devices having at least a first end; an array of optical elements having at least a first end; the first end of the array of optical elements optically aligned with the first end of the array of optoelectronic devices; an optical path extending from the first end of the array of optoelectronic devices and ending at a second end of the array of optical elements; and an attenuator in the optical path for attenuating the optical energy emitted from the array of optoelectronic devices. Alternatively, a conditioner may be adapted in the optical path for conditioning the optical energy emitted from the array of optoelectronic devices.

  11. [Evaluation of uncertainty for determination of tin and its compounds in air of workplace by flame atomic absorption spectrometry].

    PubMed

    Wei, Qiuning; Wei, Yuan; Liu, Fangfang; Ding, Yalei

    2015-10-01

    To investigate the method for uncertainty evaluation of determination of tin and its compounds in the air of workplace by flame atomic absorption spectrometry. The national occupational health standards, GBZ/T160.28-2004 and JJF1059-1999, were used to build a mathematical model of determination of tin and its compounds in the air of workplace and to calculate the components of uncertainty. In determination of tin and its compounds in the air of workplace using flame atomic absorption spectrometry, the uncertainty for the concentration of the standard solution, atomic absorption spectrophotometer, sample digestion, parallel determination, least square fitting of the calibration curve, and sample collection was 0.436%, 0.13%, 1.07%, 1.65%, 3.05%, and 2.89%, respectively. The combined uncertainty was 9.3%.The concentration of tin in the test sample was 0.132 mg/m³, and the expanded uncertainty for the measurement was 0.012 mg/m³ (K=2). The dominant uncertainty for determination of tin and its compounds in the air of workplace comes from least squares fitting of the calibration curve and sample collection. Quality control should be improved in the process of calibration curve fitting and sample collection.

  12. Room Air Conditioners; Appliance Repair--Advanced: 9027.04.

    ERIC Educational Resources Information Center

    Dade County Public Schools, Miami, FL.

    This Quinmester course includes installations, electrical and mechanical servicing, reverse cycle air conditioning, malfunctions, troubleshooting and repair, discharge, pump down, and recharging the system. The course may be taught as a two or three Quinmester credit course. In each instance the course consists of six instructional blocks:…

  13. Locally produced natural conditioners for dewatering of faecal sludge.

    PubMed

    Gold, Moritz; Dayer, Pauline; Faye, Marie Christine Amie Sene; Clair, Guillaume; Seck, Alsane; Niang, Seydou; Morgenroth, Eberhard; Strande, Linda

    2016-11-01

    In urban areas of low-income countries, treatment of faecal sludge (FS) is insufficient or non-existent. This results in large amounts of FS being dumped into the environment. Existing treatment technologies for FS, such as settling-thickening tanks and drying beds, are land intensive which is limiting in urban areas. Enhanced settling and dewatering by conditioning was evaluated in order to reduce the treatment footprint (or increase treatment capacity). Conventional wastewater conditioners, such as commercially available lime and polymers, are expensive, and commonly rely on complex supply chains for use in low-income countries. Therefore, the treatment performance of five conditioners which could be produced locally was evaluated: Moringa oleifera seeds and press cake, Jatropha curcas seeds, Jatropha Calotropis leaves and chitosan. M. oleifera seeds and press cake, and chitosan improved settling and dewatering and had a similar performance compared to lime and polymers. Optimal dosages were 400-500 kg M. oleifera/t TS, 300-800 kg lime/t TS and 25-50 kg polymer solution/t TS. In comparison, chitosan required 1.5-3.75 kg/t TS. These dosages are comparable to those recommended for wastewater (sludge). The results indicate that conditioning of FS can reduce total suspended solids (TSS) in the effluent of settling-thickening tanks by 22-81% and reduce dewatering time with drying beds by 59-97%. This means that the area of drying beds could be reduced by 59-97% with end-use as soil conditioner, or 9-26% as solid fuel. Least expensive options and availability will depend on the local context. In Dakar, Senegal, chitosan produced from shrimp waste appears to be most promising.

  14. Air conditioning system

    DOEpatents

    Lowenstein, Andrew; Miller, Jeffrey; Gruendeman, Peter; DaSilva, Michael

    2005-02-01

    An air conditioner comprises a plurality of plates arranged in a successively stacked configuration with portions thereof having a spaced apart arrangement, and defining between successive adjacent pairs of plates at the spaced apart portions a first and second series of discrete alternating passages wherein a first air stream is passed through the first series of passages and a second air stream is passed through the second series of passages; and said stacked configuration of plates forming integrally therewith a liquid delivery means for delivering from a source a sufficient quantity of a liquid to the inside surfaces of the first series of fluid passages in a manner which provides a continuous flow of the liquid from a first end to a second end of the plurality of plates while in contact with the first air stream.

  15. Measurement of the mass energy-absorption coefficient of air for x-rays in the range from 3 to 60 keV.

    PubMed

    Buhr, H; Büermann, L; Gerlach, M; Krumrey, M; Rabus, H

    2012-12-21

    For the first time the absolute photon mass energy-absorption coefficient of air in the energy range of 10 to 60 keV has been measured with relative standard uncertainties below 1%, considerably smaller than those of up to 2% assumed for calculated data. For monochromatized synchrotron radiation from the electron storage ring BESSY II both the radiant power and the fraction of power deposited in dry air were measured using a cryogenic electrical substitution radiometer and a free air ionization chamber, respectively. The measured absorption coefficients were compared with state-of-the art calculations and showed an average deviation of 2% from calculations by Seltzer. However, they agree within 1% with data calculated earlier by Hubbell. In the course of this work, an improvement of the data analysis of a previous experimental determination of the mass energy-absorption coefficient of air in the range of 3 to 10 keV was found to be possible and corrected values of this preceding study are given.

  16. Transforming PC Power Supplies into Smart Car Battery Conditioners

    ERIC Educational Resources Information Center

    Rodriguez-Ascariz, J. M.; Boquete-Vazquez, L.

    2011-01-01

    This paper describes a laboratory project consisting of a PC power supply modification into an intelligent car-battery conditioner with both wireless and wired networking capabilities. Adding a microcontroller to an average PC power supply transforms it into a flexible, intelligent device that can be configured and that is suitable to keep car…

  17. Air Conditioning Overflow Sensor

    NASA Technical Reports Server (NTRS)

    1996-01-01

    The Technology Transfer Office at Stennis Space Center helped a local inventor develop a prototype of an attachment for central air conditioners and heat pumps that helps monitor water levels to prevent condensation overflow. The sensor will indicate a need for drain line maintenance and prevent possible damage caused by drain pan water spillover. An engineer in the Stennis Space Center prototype Development Laboratory used SSC sensor technology in the development of the sensor.

  18. Cooling efficiency of a spot-type personalized air-conditioner

    DOE PAGES

    Zhu, Shengwei; Dalgo, Daniel; Srebric, Jelena; ...

    2017-08-01

    Here, this study defined Cooling Efficiency ( CE) of a Spot-type Personalized Air-Conditioning (SPAC) device as the ratio of the additional sensible heat removal from human body induced by SPAC and the device's cooling capacity. CE enabled the investigation of SPAC performance on the occupant's sensible heat loss (Q s) and thermal sensation by its quantitative relation with the change of PMV level ( ΔPMV). Three round nozzles with the diameter of 0.08 m, 0.105 m, and 0.128 m, respectively, discharged air jets at airflow rates from 11.8 L s –1 to 59.0 L s –1, toward the chest ofmore » a seated or standing human body with a clothing of 0.48 clo. This study developed a validated CFD model coupled with the Fanger's thermoregulation model, to calculate Q s in a room of 26 °C ventilated at a rate of 3 ACH. According to the results, Q s, CE and draft risk ( DR) at face had significant positive linear correlation with the SPAC device's supply airflow rates (R2 >0.96), and a negative linear correlation for ΔPMV. With DR = 20% at face, CE was always under 0.3, and ΔPMV was around -1.0–1.1. Interestingly, both CE and ΔPMV had the least favorable values for the air jet produced by the nozzle with the diameter of 0.105 m independent of body posture. In conclusion, although SPAC could lead to additional Q s by sending air at a higher airflow rate from a smaller nozzle, the improvement in cooling efficiency and thermal sensation had a limit due to draft risk.« less

  19. Locally produced natural conditioners for dewatering of faecal sludge

    PubMed Central

    Gold, Moritz; Dayer, Pauline; Faye, Marie Christine Amie Sene; Clair, Guillaume; Seck, Alsane; Niang, Seydou; Morgenroth, Eberhard; Strande, Linda

    2016-01-01

    ABSTRACT In urban areas of low-income countries, treatment of faecal sludge (FS) is insufficient or non-existent. This results in large amounts of FS being dumped into the environment. Existing treatment technologies for FS, such as settling-thickening tanks and drying beds, are land intensive which is limiting in urban areas. Enhanced settling and dewatering by conditioning was evaluated in order to reduce the treatment footprint (or increase treatment capacity). Conventional wastewater conditioners, such as commercially available lime and polymers, are expensive, and commonly rely on complex supply chains for use in low-income countries. Therefore, the treatment performance of five conditioners which could be produced locally was evaluated: Moringa oleifera seeds and press cake, Jatropha curcas seeds, Jatropha Calotropis leaves and chitosan. M. oleifera seeds and press cake, and chitosan improved settling and dewatering and had a similar performance compared to lime and polymers. Optimal dosages were 400–500 kg M. oleifera/t TS, 300–800 kg lime/t TS and 25–50 kg polymer solution/t TS. In comparison, chitosan required 1.5–3.75 kg/t TS. These dosages are comparable to those recommended for wastewater (sludge). The results indicate that conditioning of FS can reduce total suspended solids (TSS) in the effluent of settling-thickening tanks by 22–81% and reduce dewatering time with drying beds by 59–97%. This means that the area of drying beds could be reduced by 59–97% with end-use as soil conditioner, or 9–26% as solid fuel. Least expensive options and availability will depend on the local context. In Dakar, Senegal, chitosan produced from shrimp waste appears to be most promising. PMID:26984372

  20. Thermionic reactor power conditioner design for nuclear electric propulsion.

    NASA Technical Reports Server (NTRS)

    Jacobsen, A. S.; Tasca, D. M.

    1971-01-01

    Consideration of the effects of various thermionic reactor parameters and requirements upon spacecraft power conditioning design. A basic spacecraft is defined using nuclear electric propulsion, requiring approximately 120 kWe. The interrelationships of reactor operating characteristics and power conditioning requirements are discussed and evaluated, and the effects on power conditioner design and performance are presented.

  1. A CSMP Commutation Model for Design Study of a Brushless DC Motor Power Conditioner for a Cruise Missile Fin Control Actuator.

    DTIC Science & Technology

    1985-06-01

    STUDY OF A BRUSHLESS DC MOTOR POWER CONDITIONER FOR A CRUISE MISSILE FIN CONTROL ACTUATOR CA. by Peter Norman MacMillan June 1985 Thesis Advisor: A...TYPE OF REPORT & PERIOD COVERED A CSMP Commutation Model for Design Master’s Thesis Study of a Brushless DC Motor Power June, 1985 Conditioner for a...tactical missiles. A dynamic equivalent circuit model for the analysis of a small four pole brushless DC motor fed ty a transistorized power conditioner

  2. [Effectiveness of the maintenance operations on the air conditioning systems of a university building in relation to the microbiological quality of the air indoor].

    PubMed

    De Filippis, Patrizia; Spinaci, Anna; Coia, Maura; Maggi, Oriana; Panà, Augusto

    2003-01-01

    The microbiological quality of the air indoor is influenced from various factors and one of the most important is represented from the maintenance of the conditioning systems. In this study it has been estimated the effectiveness of an intervention of cleaning and maintenance on the systems of conditioning of an university building executing sampling before and after such intervention. The two results were confronted and it is observed as the maintenance of the air conditioners has influenced on the quality of the air indoor.

  3. Dynamic modeling of brushless dc motor-power conditioner unit for electromechanical actuator application

    NASA Technical Reports Server (NTRS)

    Demerdash, N. A.; Nehl, T. W.

    1979-01-01

    A comprehensive digital model for the analysis of the dynamic-instantaneous performance of a power conditioner fed samarium-cobalt permanent magnet brushless DC motor is presented. The particular power conditioner-machine system at hand, for which this model was developed, is a component of an actual prototype electromechanical actuator built for NASA-JSC as a possible alternative to hydraulic actuators as part of feasibility studies for the shuttle orbiter applications. Excellent correlation between digital simulated and experimentally obtained performance data was achieved for this specific prototype. This is reported on in this paper. Details of one component of the model, its applications and the corresponding results are given in this paper.

  4. Analysis of an Affordability Index Model for Marine Corps Ground Combat Equipment

    DTIC Science & Technology

    2004-12-01

    Generator, TSEC/KG-40A/P A8100 10 Control Group, Radio, OK648/U B0001 21 Air - Conditioner 60Hz, 9,000 Btu B0002 21 Air - Conditioner 60Hz, 18,000...Btu, F18H-38A B0007 21 Air - Conditioner MCS Vertical 60K, Btu, FOOT-2HS B0011 21 Air - Conditioner A/E 32C-39, 18K Btu B0012 21 Air Conditioner ...supply system. For example, it is possible for a motor transportation mechanic to have the parts for two or more MARES reportable, combat-deadlined

  5. High efficiency laser spectrum conditioner

    DOEpatents

    Greiner, Norman R.

    1980-01-01

    A high efficiency laser spectrum conditioner for generating a collinear parallel output beam containing a predetermined set of frequencies from a multifrequency laser. A diffraction grating and spherical mirror are used in combination, to disperse the various frequencies of the input laser beam and direct these frequencies along various parallel lines spatially separated from one another to an apertured mask. Selection of the desired frequencies is accomplished by placement of apertures at locations on the mask where the desired frequencies intersect the mask. A recollimated parallel output beam with the desired set of frequencies is subsequently generated utilizing a mirror and grating matched and geometrically aligned in the same manner as the input grating and mirror.

  6. Experimental evaluation of refrigerant mass charge and ambient air temperature effects on performance of air-conditioning systems

    NASA Astrophysics Data System (ADS)

    Deymi-Dashtebayaz, Mahdi; Farahnak, Mehdi; Moraffa, Mojtaba; Ghalami, Arash; Mohammadi, Nima

    2018-03-01

    In this paper the effects of refrigerant charge amount and ambient air temperature on performance and thermodynamic condition of refrigerating cycle in the split type air-conditioner have been investigated. Optimum mass charge is the point at which the energy efficiency ratio (EER) of refrigeration cycle becomes the maximum. Experiments have been conducted over a range of refrigerant mass charge from 540 to 840 g and a range of ambient temperature from 27 to 45 °C, in a 12,000 Btu/h split air-conditioner as case study. The various parameters have been considered to evaluate the cooling rate, energy efficiency ratio (EER), mass charge effect and thermodynamic cycle of refrigeration system with R22 refrigerant gas. Results confirmed that the lack of appropriate refrigerant mass charge causes the refrigeration system not to reach its maximum cooling capacity. The highest cooling capacity achieved was 3.2 kW (11,000 Btu/h). The optimum mass charge and corresponding EER of studied system have been obtained about 640 g and 2.5, respectively. Also, it is observed that EER decreases by 30% as ambient temperature increases from 27 °C to 45 °C. By optimization of the refrigerant mass charge in refrigerating systems, about 785 GWh per year of electric energy can be saved in Iran's residential sector.

  7. 21 CFR 872.3750 - Bracket adhesive resin and tooth conditioner.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... composed of an adhesive compound, such as polymethylmethacrylate, intended to cement an orthodontic bracket... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Bracket adhesive resin and tooth conditioner. 872... SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3750 Bracket adhesive resin...

  8. Cell module and fuel conditioner development

    NASA Technical Reports Server (NTRS)

    Hoover, D. Q., Jr.

    1981-01-01

    The test results of and post test analysis of Stack 559 are reported. The design features and construction status of Stacks 560, 561, 562 and 563 are described. The measurements of cell materials compressibility are rationalized and summarized and an explanation of their uses is given. Preliminary results of a manifold material/coating survey are given. The results of shift converter catalyst performance tests and reforming catalyst aging tests are reported. State points for full load and part load operation of the fuel conditioning subsystem tabulated. Work on the data base for the fuel conditioner ancillary subsystems is summarized.

  9. Flow conditioner for fuel injector for combustor and method for low-NO.sub.x combustor

    DOEpatents

    Dutta, Partha; Smith, Kenneth O.; Ritz, Frank J.

    2013-09-10

    An injector for a gas turbine combustor including a catalyst coated surface forming a passage for feed gas flow and a channel for oxidant gas flow establishing an axial gas flow through a flow conditioner disposed at least partially within an inner wall of the injector. The flow conditioner includes a length with an interior passage opening into upstream and downstream ends for passage of the axial gas flow. An interior diameter of the interior passage smoothly reduces and then increases from upstream to downstream ends.

  10. Aerosol Light Absorption and Scattering Assessments and the Impact of City Size on Air Pollution

    NASA Astrophysics Data System (ADS)

    Paredes-Miranda, Guadalupe

    The general problem of urban pollution and its relation to the city population is examined in this dissertation. A simple model suggests that pollutant concentrations should scale approximately with the square root of city population. This model and its experimental evaluation presented here serve as important guidelines for urban planning and attainment of air quality standards including the limits that air pollution places on city population. The model was evaluated using measurements of air pollution. Optical properties of aerosol pollutants such as light absorption and scattering plus chemical species mass concentrations were measured with a photoacoustic spectrometer, a reciprocal nephelometer, and an aerosol mass spectrometer in Mexico City in the context of the multinational project "Megacity Initiative: Local And Global Research Observations (MILAGRO)" in March 2006. Aerosol light absorption and scattering measurements were also obtained for Reno and Las Vegas, NV USA in December 2008-March 2009 and January-February 2003, respectively. In all three cities, the morning scattering peak occurs a few hours later than the absorption peak due to the formation of secondary photochemically produced aerosols. In particular, for Mexico City we determined the fraction of photochemically generated secondary aerosols to be about 75% of total aerosol mass concentration at its peak near midday. The simple 2-d box model suggests that commonly emitted primary air pollutant (e.g., black carbon) mass concentrations scale approximately as the square root of the urban population. This argument extends to the absorption coefficient, as it is approximately proportional to the black carbon mass concentration. Since urban secondary pollutants form through photochemical reactions involving primary precursors, in linear approximation their mass concentration also should scale with the square root of population. Therefore, the scattering coefficient, a proxy for particulate matter

  11. Measure Guideline: Air Conditioner Diagnostics, Maintenance, and Replacement

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Springer, D.; Dakin, B.

    2013-03-01

    This guideline responds to the need for an efficient means of identifying, diagnosing, and repairing faults in air conditioning systems in existing homes that are undergoing energy upgrades. Inadequate airflow due to constricted ducts or undersized filters, improper refrigerant charge, and other system defects can be corrected at a fraction of the cost of equipment replacement and can yield significant savings. The guideline presents a two-step approach to diagnostics and repair.

  12. Measure Guideline. Air Conditioner Diagnostics, Maintenance, and Replacement

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Springer, David; Dakin, Bill

    2013-03-01

    This guideline responds to the need for an efficient means of identifying, diagnosing, and repairing faults in air conditioning systems in existing homes that are undergoing energy upgrades. Inadequate airflow due to constricted ducts or undersized filters, improper refrigerant charge, and other system defects can be corrected at a fraction of the cost of equipment replacement and can yield significant savings. The guideline presents a two-step approach to diagnostics and repair.

  13. Improved bonding of adhesive resin to sintered porcelain with the combination of acid etching and a two-liquid silane conditioner.

    PubMed

    Kato, H; Matsumura, H; Ide, T; Atsuta, M

    2001-01-01

    This study determined the bond strengths of adhesive resins joined to a feldspathic porcelain (VMK 68) for the purpose of developing the most durable surface preparation for the porcelain. Three porcelain surfaces-ground, air-abraded with alumina, and etched with hydrofluoric acid-were prepared. A two-liquid porcelain conditioner that contained both 4-methacryloyloxyethyl trimellitate anhydride (4-META) and a silane coupler (Porcelain Liner M) was used as the priming agent. Each of the two liquid components of the conditioner was also used individually in order to examine the effects of the respective chemical ingredients on adhesive bonding. Two methyl methacrylate (MMA)-based resins initiated with tri-n-butylborane (TBB) either with or without 4-META (MMA-TBB and 4-META/MMA-TBB resins) were used as the luting agents. Shear bond strengths were determined both before and after thermocycling. Shear testing results indicated that thermocycling was effective for disclosing poor bonding systems, and that both mechanical and chemical retention were indispensable for bonding the porcelain. Of the combinations assessed, etching with hydrofluoric acid followed by two-liquid priming with the Porcelain Liner M material generated the most durable bond strength (33.3 MPa) for the porcelain bonded with the 4-META/MMA-TBB resin (Super-Bond C&B).

  14. Improved hopcalite procedure for the determination of mercury vapor in air by flameless atomic absorption.

    PubMed

    Rathje, A O; Marcero, D H

    1976-05-01

    Mercury vapor is efficiently trapped from air by passage through a small glass tube filled with hopcalite. The hopcalite and adsorbed mercury are dissolved in a mixture of nitric and hydrochloric acids. Solution is rapid and complete, with no loss of mercury. Analysis is completed by flameless atomic absorption.

  15. Effect of PMMA polymer on the dynamic viscoelasticity and plasticizer leachability of PEMA-based tissue conditioners.

    PubMed

    Hong, Guang; Maeda, Takeshi; Li, YingAi; Sadamori, Shinsuke; Hamada, Taizo; Murata, Hiroshi

    2010-08-01

    The purpose of this study was to determine the effect of PMMA polymer on dynamic viscoelasticity and plasticizer leachability of PEMA-based tissue conditioners. One PEMA polymer and one PMMA polymer were used in powder form with four formulations. The combination of 80 wt% ATBC, 15 wt% BPBG and 5 wt% ethyl alcohol was used as the liquid phase. The dynamic viscoelasticity and plasticizer leaching of each specimen were measured after 0, 1, 3, 7, and 14 days of immersion (37 degrees C distilled water) using DMA and HPLC. A significant difference was found among the materials in the dynamic viscoelasticity and leaching of plasticizer. The materials containing 10 wt% PMMA showed the most stable dynamic viscoelasticity, and showed the lowest leaching of plasticizer. The results suggest that the addition of the PMMA polymer to the powder of a tissue conditioner can improve the durability of the PEMA-based tissue conditioner.

  16. Research Proposal for the Design and Engineering Phase of a Solar Heating and Cooling System Experiment at the Warner Robins Public Library, Warner Robins, Georgia. Submitted to the United States Energy Research and Development Administration.

    ERIC Educational Resources Information Center

    Phillips, Warren H.; And Others

    A number of reasons are advanced to include a solar heating and cooling experiment in a library building. The unique aspects of the experiment are to be a seasonally adjustable collector tilt and testing of a new generation of absorption air conditioners. After a brief description of the proposed experiment, the proposal contains forms filed by…

  17. 21 CFR 872.3765 - Pit and fissure sealant and conditioner.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Pit and fissure sealant and conditioner. 872.3765 Section 872.3765 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3765 Pit and fissure sealant and...

  18. Enabling Smart Air Conditioning by Sensor Development: A Review

    PubMed Central

    Cheng, Chin-Chi; Lee, Dasheng

    2016-01-01

    The study investigates the development of sensors, in particular the use of thermo-fluidic sensors and occupancy detectors, to achieve smart operation of air conditioning systems. Smart operation refers to the operation of air conditioners by the reinforcement of interaction to achieve both thermal comfort and energy efficiency. Sensors related to thermal comfort include those of temperature, humidity, and pressure and wind velocity anemometers. Improvements in their performance in the past years have been studied by a literature survey. Traditional occupancy detection using passive infra-red (PIR) sensors and novel methodologies using smartphones and wearable sensors are both discussed. Referring to the case studies summarized in this study, air conditioning energy savings are evaluated quantitatively. Results show that energy savings of air conditioners before 2000 was 11%, and 30% after 2000 by the integration of thermo-fluidic sensors and occupancy detectors. By utilizing wearable sensing to detect the human motions, metabolic rates and related information, the energy savings can reach up to 46.3% and keep the minimum change of predicted mean vote (∆PMV→0), which means there is no compromise in thermal comfort. This enables smart air conditioning to compensate for the large variations from person to person in terms of physiological and psychological satisfaction, and find an optimal temperature for everyone in a given space. However, this tendency should be evidenced by more experimental results in the future. PMID:27916906

  19. Evaluation of a clay-based acidic bedding conditioner for dairy cattle bedding.

    PubMed

    Proietto, R L; Hinckley, L S; Fox, L K; Andrew, S M

    2013-02-01

    This study investigated the effects of a clay-based acidic bedding conditioner on sawdust bedding pH, dry matter (DM), environmental pathogen counts, and environmental bacterial counts on teat ends of lactating dairy cows. Sixteen lactating Holstein cows were paired based on parity, days in milk, milk yield, and milk somatic cell count, and were negative for the presence of an intramammary pathogen. Within each pair, cows were randomly assigned to 1 of 2 treatments with 3-wk periods in a crossover design. Treatment groups consisted of 9 freestalls per group bedded with either untreated sawdust or sawdust with a clay-based acidic bedding conditioner, added at 3- to 4-d intervals over each 21-d period. Bedding and teat ends were aseptically sampled on d 0, 1, 2, 7, 14, and 21 for determination of environmental bacterial counts. At the same time points, bedding was sampled for DM and pH determination. The bacteria identified in the bedding material were total gram-negative bacteria, Streptococcus spp., and coliform bacteria. The bacteria identified on the teat ends were Streptococcus spp., coliform bacteria, and Klebsiella spp. Teat end score, milk somatic cell count, and intramammary pathogen presence were measured weekly. Bedding and teat cleanliness, environmental high and low temperatures, and dew point data were collected daily. The bedding conditioner reduced the pH, but not the DM, of the sawdust bedding compared with untreated sawdust. Overall environmental bacterial counts in bedding were lower for treated sawdust. Total bacterial counts in bedding and on teat ends increased with time over both periods. Compared with untreated sawdust, the treated bedding had lower counts of total gram-negative bacteria and streptococci, but not coliform counts. Teat end bacterial counts were lower for cows bedded on treated sawdust for streptococci, coliforms, and Klebsiella spp. compared with cows bedded on untreated sawdust. The clay-based acidic bedding conditioner

  20. Detection of Dermatophagoides farinae in the dust of air conditioning filters.

    PubMed

    Liu, Zhigang; Bai, Yu; Ji, Kunmei; Liu, Xiaoyu; Cai, Chengyu; Yu, Haiqiong; Li, Meng; Bao, Ying; Lian, Yuyin; Gao, Bo

    2007-01-01

    The allergenic dust mite species Dermatophagoides pteronyssinus and Dermatophagoides farinae generally inhabit warm moist environments. This study tested the hypothesis that these allergenic species may thrive in air conditioner filters. A year-long investigation of the dust mite population densities and species identities living in air conditioner filters in Shenzhen City in Southern China was performed. Additional data describing the levels of major dust mite allergen proteins from samples collected in July and August 2004 were analyzed. Genetic polymorphism analysis of Der f 1 and Der f 2 genes in the collected animals was also conducted. Our investigation revealed that larval dust mites started to grow in March, from which time their populations proceeded to steadily increase until reaching their population zenith in July and August. The dust mite populations decreased sharply in October and live dust mites were no longer observed in the winter. Among the mites collected in July and August, 30.1 and 25.8% were of the species D. farinae. The concentration of Der f 1 was 3.04 +/- 1.75 and 3.21 +/- 1.84 microg/g dust in July and August, respectively, and that of Der f 2 was 2.15 +/- 0.82 and 2.04 +/- 1.15 microg/g dust. Four types of Der f 1 and 5 types of Der f 2 cDNA sequences were cloned from collected Der f mites. Their sequences were highly homologous with those previously published in GenBank (No. AB034946.1 and No. AB195580.1). This research demonstrated that Der f allergens exist in the dust of air conditioner filters in this area.

  1. 78 FR 77019 - Energy Conservation Program: Energy Conservation Standards for Certain Consumer Products

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-12-20

    ... Regulations the definitions for ``through-the-wall central air conditioner'' and ``through-the-wall central... superseded effective in 2006, and the now defunct references to the ``through-the-wall air conditioner and... definitions for ``through-the-wall central air conditioner'' and ``through-the-wall central air conditioning...

  2. 24 CFR 3280.811 - Calculations.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... motors and heater loads (exhaust fans, air conditioners, electric, gas, or oil heating). Omit smaller of air conditioning and heating except include blower motor if used as air conditioner evaporator motor. When an air conditioner is not installed and a 40-ampere power supply cord is provided, allow 15...

  3. The Development of a Set of Conditioning Tasks to Measure Conditionability as a Stable Aspect of Behavior--A Feasibility Study.

    ERIC Educational Resources Information Center

    Strong, Emily; Vallery, Arlee

    Tests of conditionability in infants were used in a longidudinal study of 32 subjects in the first year of life. The research was based on Eysenck's hypothesis that conditionability i s a unitary factor related to introversion-extroversion and attention span. The objective of the investigators was to devise a battery of conditioning tasks…

  4. Method and apparatus for analog signal conditioner for high speed, digital x-ray spectrometer

    DOEpatents

    Warburton, W.K.; Hubbard, B.

    1999-02-09

    A signal processing system which accepts input from an x-ray detector-preamplifier and produces a signal of reduced dynamic range for subsequent analog-to-digital conversion is disclosed. The system conditions the input signal to reduce the number of bits required in the analog-to-digital converter by removing that part of the input signal which varies only slowly in time and retaining the amplitude of the pulses which carry information about the x-rays absorbed by the detector. The parameters controlling the signal conditioner`s operation can be readily supplied in digital form, allowing it to be integrated into a feedback loop as part of a larger digital x-ray spectroscopy system. 13 figs.

  5. Design of a signal conditioner for the Fermilab Magnet Test Facility

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Giannelli, Pietro

    2012-01-01

    This thesis describes the design of a remotely-programmable signal conditioner for the harmonic measurement of accelerator magnets. A 10-channel signal conditioning circuit featuring bucking capabilities was designed from scratch and implemented to the level of the printed circuit board layout. Other system components were chosen from those available on the market. Software design was started with the definition of routine procedures. This thesis is part of an upgrade project for replacing obsolescent automated test equipment belonging to the Fermilab Magnet Test Facility. The design started with a given set of requirements. Using a top-down approach, all the circuits were designedmore » and their expected performances were theoretically predicted and simulated. A limited prototyping phase followed. The printed circuit boards were laid out and routed using a CAD software and focusing the design on maximum electromagnetic interference immunity. An embedded board was selected for controlling and interfacing the signal conditioning circuitry with the instrumentation network. Basic low level routines for hardware access were defined. This work covered the entire design process of the signal conditioner, resulting in a project ready for manufacturing. The expected performances are in line with the requirements and, in the cases where this was not possible, approval of trade-offs was sought and received from the end users. Part I deals with the global structure of the signal conditioner and the subdivision in functional macro-blocks. Part II treats the hardware design phase in detail, covering the analog and digital circuits, the printed circuit layouts, the embedded controller and the power supply selection. Part III deals with the basic hardware-related routines to be implemented in the final software.« less

  6. 78 FR 17890 - Energy Efficiency Program for Commercial and Industrial Equipment: Public Meeting and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-25

    ... Document for Packaged Terminal Air Conditioners and Packaged Terminal Heat Pumps AGENCY: Office of Energy... must identify the framework document for packaged terminal air conditioners and packaged terminal heat... packaged terminal air conditioners and packaged terminal heat pumps. 78 FR 12252. The document provided for...

  7. 76 FR 27610 - Approval and Promulgation of Air Quality Implementation Plans; Maryland; Adoption of Control...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-12

    ..., freezers, water heaters, dishwashers, trash compactors, air conditioners, ovens, microwave ovens, and other... appliance product. A large appliance product is also defined as any organic surface-coated metal range, oven, microwave, refrigerator, freezer, washer, dryer, dishwasher, water heater, or trash compactor manufactured...

  8. 10 CFR 431.95 - Materials incorporated by reference.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... INDUSTRIAL EQUIPMENT Commercial Air Conditioners and Heat Pumps Test Procedures § 431.95 Materials... Packaged Terminal Air-Conditioners and Heat Pumps,” published September 2004 (AHRI 310/380-2004), IBR... Single Package Vertical Air-Conditioners and Heat Pumps,” dated 2003, (AHRI 390-2003), IBR approved for...

  9. 10 CFR 431.95 - Materials incorporated by reference.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... INDUSTRIAL EQUIPMENT Commercial Air Conditioners and Heat Pumps Test Procedures § 431.95 Materials... Packaged Terminal Air-Conditioners and Heat Pumps,” published September 2004 (AHRI 310/380-2004), IBR... Single Package Vertical Air-Conditioners and Heat Pumps,” dated 2003, (AHRI 390-2003), IBR approved for...

  10. 10 CFR 431.96 - Uniform test method for the measurement of energy efficiency of small, large, and very large...

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ..., packaged terminal air conditioners, and packaged terminal heat pumps. 431.96 Section 431.96 Energy... EQUIPMENT Commercial Air Conditioners and Heat Pumps Test Procedures § 431.96 Uniform test method for the... heating equipment, packaged terminal air conditioners, and packaged terminal heat pumps. (a) Scope. This...

  11. 10 CFR 431.96 - Uniform test method for the measurement of energy efficiency of small, large, and very large...

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ..., packaged terminal air conditioners, and packaged terminal heat pumps. 431.96 Section 431.96 Energy... EQUIPMENT Commercial Air Conditioners and Heat Pumps Test Procedures § 431.96 Uniform test method for the... heating equipment, packaged terminal air conditioners, and packaged terminal heat pumps. (a) Scope. This...

  12. Wavelet based de-noising of breath air absorption spectra profiles for improved classification by principal component analysis

    NASA Astrophysics Data System (ADS)

    Kistenev, Yu. V.; Shapovalov, A. V.; Borisov, A. V.; Vrazhnov, D. A.; Nikolaev, V. V.; Nikiforova, O. Yu.

    2015-11-01

    The comparison results of different mother wavelets used for de-noising of model and experimental data which were presented by profiles of absorption spectra of exhaled air are presented. The impact of wavelets de-noising on classification quality made by principal component analysis are also discussed.

  13. Enhanced light absorptivity of black carbon with air pollution development in urban Beijing, China

    NASA Astrophysics Data System (ADS)

    Zhang, Y.; Zhang, Q.; Cheng, Y.; Su, H.; He, K.

    2017-12-01

    The impacts of black carbon (BC) aerosols on air quality and climate are dependent on BC light absorptivity. However, the light absorptivity of ambient BC-containing particles remains conflicting. In this work, we investigated the evolution of BC light absorptivity with pollution development in urban Beijing, China. We found that the mass absorption cross-section (MAC) of ambient BC-containing particles measured during the campaign increased with BC mass concentration, which can be attributed to more coating materials on BC surface with pollution development. A single-particle soot photometer (SP2) measurement showed that the coating thickness (CT) of BC-containing particles increased by 48% with PM1 and BC mass concentration increasing from 10 μg m-3 and 0.3 μg m-3 to 230 μg m-3 and 12 μg m-3. Based on Mie calculation, the CT increase could led to light absorption enhancement (Eab) of BC-containing particles increasing by 22%, consistent with the increase of measured MAC. The relationship between growth rate of BC light absorptivity (kEab) and that of PM1 or rBC concentration (kPM1 or krBC) showed that kEab ≈ 4.8% kPM1 or kEab ≈ 2.5% krBC. The analysis of effective emission intensity (EEI) for BC revealed that the enhancement of BC light absorptivity with increasing pollution levels was dominated by regional transport. During the pollution period, 63% of BC over Beijing originated from regional sources. The aging of these regional BC during atmospheric transport controlled the increase of coating materials for BC-containing particles observed in Beijing. As a result of enhanced light absorptivity with pollution development, BC forcing efficiency could increase by 20% during polluted period. Our work identified the importance of BC on radiative forcing under polluted environment, which is determined by not only the increase of BC mass concentration, but also the enhancement of BC forcing efficiency due to more coating materials.

  14. Effect of Two Traditional Polyacrylic Acid Conditioners and 2% Chlorhexidine Digluconate on Cavosurface Microleakage of Glass Ionomer Restorations.

    PubMed

    Lugassy, Diva; Segal, Pnina; Blumer, Sigalit; Eger, Michal; Shely, Asaf; Matalon, Shlomo

    2018-05-11

    A lack of appropriate adhesiveness is one of the biggest problems in restorative dentistry today and the main cause of microleakage. This is especially true in pediatric dentistry where moisture control is more difficult to achieve. Glass ionomer restorative materials increase adhesion and decrease microleakage given their chemical adhesion to the remaining tooth substance. Pretreatment improves the adhesion quality. The aim of this study was to assess the microleakage of Glass ionomer restorative materials following application of 20% polyacrylic acid, 10% polyacrylic acid or 2% chlorhexidine digluconate in Class V cavities. Two Class V preparations were prepared on the buccal and lingual surfaces of 24 extracted human molars. The gingival wall was set below or above the CEJ. The teeth were divided into 2 groups. Group 1 was treated with 20% polyacrylic acid or 10% polyacrylic acid. Group 2 was treated with 10% polyacrylic acid or 2% chlorhexidine digluconate. Microleakage was evaluated using a light-reflecting stereomicroscope and stain penetration test. Two percent chlorhexidine digluconate was as efficient as the other conditioners. No statistically significant differences were found among the three types of conditioners. Dye penetration was significantly greater into dentin than into enamel among all three conditioners in both groups (P<0.001). Two percent chlorhexidine digluconate, with its known added advantages, can be used as a pretreatment conditioner in GI restorations.

  15. 40 CFR 82.30 - Purpose and scope.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... STRATOSPHERIC OZONE Servicing of Motor Vehicle Air Conditioners § 82.30 Purpose and scope. (a) The purpose of...) regarding the servicing of motor vehicle air conditioners (MVACs), and to implement section 608 of the Act regarding certain servicing, maintenance, repair and disposal of air conditioners in MVACs and MVAC-like...

  16. 10 CFR 431.95 - Materials incorporated by reference.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... INDUSTRIAL EQUIPMENT Commercial Air Conditioners and Heat Pumps Test Procedures § 431.95 Materials...) published in 2004, “Standard for Packaged Terminal Air-Conditioners and Heat Pumps,” IBR approved for § 431... for Commercial Air Conditioners and Heat Pumps,” Docket No. EE-RM/TP-99-460, 1000 Independence Avenue...

  17. 40 CFR 82.30 - Purpose and scope.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... STRATOSPHERIC OZONE Servicing of Motor Vehicle Air Conditioners § 82.30 Purpose and scope. (a) The purpose of...) regarding the servicing of motor vehicle air conditioners (MVACs), and to implement section 608 of the Act regarding certain servicing, maintenance, repair and disposal of air conditioners in MVACs and MVAC-like...

  18. 40 CFR 82.30 - Purpose and scope.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... STRATOSPHERIC OZONE Servicing of Motor Vehicle Air Conditioners § 82.30 Purpose and scope. (a) The purpose of...) regarding the servicing of motor vehicle air conditioners (MVACs), and to implement section 608 of the Act regarding certain servicing, maintenance, repair and disposal of air conditioners in MVACs and MVAC-like...

  19. 40 CFR 82.30 - Purpose and scope.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... STRATOSPHERIC OZONE Servicing of Motor Vehicle Air Conditioners § 82.30 Purpose and scope. (a) The purpose of...) regarding the servicing of motor vehicle air conditioners (MVACs), and to implement section 608 of the Act regarding certain servicing, maintenance, repair and disposal of air conditioners in MVACs and MVAC-like...

  20. 40 CFR 82.30 - Purpose and scope.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... STRATOSPHERIC OZONE Servicing of Motor Vehicle Air Conditioners § 82.30 Purpose and scope. (a) The purpose of...) regarding the servicing of motor vehicle air conditioners (MVACs), and to implement section 608 of the Act regarding certain servicing, maintenance, repair and disposal of air conditioners in MVACs and MVAC-like...

  1. EER, COP, and the Second Law Efficiency for Air Conditioners

    ERIC Educational Resources Information Center

    Leff, Harvey S.; Teeters, William D.

    1978-01-01

    Describes the relationship existing between coefficient of performance (COP) and energy efficiency ratio (EER) in air conditioning units and introduces new efficiency parameters measured relative to the energy extracted from the primary energy source. (SL)

  2. Laser-Induced Plasmas in Ambient Air for Incoherent Broadband Cavity-Enhanced Absorption Spectroscopy

    NASA Astrophysics Data System (ADS)

    Ruth, Albert A.; Dixneuf, Sophie; Orphal, Johannes

    2015-06-01

    The emission from a laser-induced plasma in ambient air, generated by a high power femtosecond laser, was utilized as pulsed incoherent broadband light source in the center of a quasi-confocal high finesse cavity. The time dependent spectra of the light leaking from the cavity was compared with those of the laser-induced plasma emission without the cavity. It was found that the light emission was sustained by the cavity despite the initially large optical losses of the laser-induced plasma in the cavity. The light sustained by the cavity was used to measure part of the S_1←S_0 absorption spectrum of gaseous azulene at its vapour pressure at room temperature in ambient air as well as the strongly forbidden γ--band in molecular oxygen: b^1σ^+_g (ν'=2)← X^3σ^-_g (ν''=0)

  3. Design and demonstration of a storage-assisted air conditioning system

    NASA Astrophysics Data System (ADS)

    Rizzuto, J. E.

    1981-03-01

    The system is a peak-shaving system designed to provide a levelized air conditioning load. The system also requires minimum air conditioner and thermal storage capacity. The storage-assisted air conditioning system uses a Glauber's salt-based phase change material in sausage like containers called CHUBS. The CHUBS are two (2) inches in diameter and 20 inches long. They are stacked in modules of 64 CHUBS which are appropriately spaced and oriented in the storage system so that air may pass perpendicular to the long axis of the CHUBS. The phase change material, has a thermal storage capacity in the range of 45 to 50 Btu/lb and a transition temperature of approximately 55 F.

  4. Interactions of soil conditioner with other limiting factors to achieve high crop yields. [Lycopersicon esculentum

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wallace, A.; Abouzamzam, A.M.

    Tomato (Lycopersicon esculentum Mill. cv. Tropic) was used as a test plant in evaluating the interactions for simultaneously correcting deficiencies of N and P and improving physical properties of soil with a soil conditioner. The three limiting factors were improved singly and in all possible combinations. There was response to each input. The least response to the soil conditioner was with N and P, and the most response was when N and P were also used. The combined effect appeared to be synergistic. The results emphasize that the best crop management system involves overcoming as many limiting factors as possible.more » This is the key to high-yield agriculture.« less

  5. 16 CFR 305.7 - Determinations of capacity.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... appendix P to 10 CFR part 430, subpart B. (f) Room air conditioners. The capacity shall be the cooling... 430, subpart B. (i) Central air conditioners, cooling. The capacity shall be the cooling capacity in... capacities between 38,000 and 64,999 Btu's per hour. (j) Central air conditioners, heating. The capacity...

  6. 16 CFR 305.7 - Determinations of capacity.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... determined according to appendix P to 10 CFR part 430, subpart B. (f) Room air conditioners. The capacity... 10 CFR part 430, subpart B. (i) Central air conditioners, cooling. The capacity shall be the cooling... hour for capacities between 38,000 and 64,999 Btu's per hour. (j) Central air conditioners, heating...

  7. Accelerating Improvements in the Energy Efficiency of Room Air Conditioners (RACs) in India: Potential, Cost-Benefit, and Policies (Interim Assessment)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Abhyankar, Nikit; Shah, Nihar; Park, Won Young

    Falling AC prices, increasing incomes, increasing urbanization, and high cooling requirements due to hot climate are all driving increasing uptake of Room Air Conditioners (RACs) in the Indian market. Air conditioning already comprises 40-60% of summer peak load in large metropolitan Indian cities such as Delhi and is likely to contribute 150 GW to the peak demand in 2030. Standards and labeling policies have contributed to improving the efficiency of RACs in India by about 2.5% in the last 10 years (2.5% per year) while inflation adjusted RAC prices have continued to decline. In this paper, we assess the technicalmore » feasibility, cost-benefit, and required policy enhancements by further accelerating the efficiency improvement of RACs in India. We find that there are examples of significantly more accelerated improvements such as those in Japan and Korea where AC efficiency improved by more than 7% per year resulting in almost a doubling of energy efficiency in 7 to 10 years while inflation adjusted AC prices continued to decline. We find that the most efficient RAC sold on the Indian market is almost twice as efficient as the typical AC sold on the market and hence see no technology constraints in a similar acceleration of improvement of efficiency. If starting 2018, AC efficiency improves at a rate of 6% instead of 3%, 40-60 GW of peak load (equivalent to connected load of 5-6 billion LED bulbs), and over 75 TWh/yr (equivalent to 60 million consumers consuming 100 kWh/month) will be saved by 2030; total peak load reduction would be as high as 50 GW. The net present value (NPV) of the consumer benefit between 2018-2030 will range from Rs 18,000 Cr in the most conservative case (in which prices don’t continue to decline and increase based estimates of today’s cost of efficiency improvement) to 140,000 Cr in a more realistic case (in which prices are not affected by accelerated efficiency improvement as shown by historical experience). This benefit is

  8. 76 FR 65616 - Energy Conservation Program for Consumer Products: Test Procedures for Residential Central Air...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-24

    ... measure the energy efficiency, energy use or estimated annual operating cost of a covered product over an... the June 2010 NOPR would be used to determine the average power consumption of a residential central... residential central air conditioners, the unit's average power consumption during the heating season...

  9. A CSMP commutation model for design study of a brushless dc motor power conditioner for a cruise missile fin control actuator

    NASA Astrophysics Data System (ADS)

    MacMillan, P. N.

    1985-06-01

    Recent improvements in rare earth magnets have made it possible to construct strong, lightweight, high horsepower dc motors. This has occasioned a reassessment of electromechanical actuators as alternatives to comparable pneumatic and hydraulic systems for use as flight control actuators for tactical missiles. A dynamic equivalent circuit model for the analysis of a small four pole brushless dc motor fed by a transistorized power conditioner utilizing high speed switching power transistors as final elements is presented. The influence of electronic commutation on instantaneous dynamic motor performance is particularly demonstrated and good correlation between computer simulation and typical experimentally obtained performance data is achieved. The model is implemented in CSMP language and features more accurate air gap flux representation over previous work. Hall effect sensor rotor position feedback is simulated. Both constant and variable air gap flux is modeled and the variable flux model treats the flux as a fundamental and one harmonic.

  10. Fabrication of Functional Polyurethane/Rare Earth Nanocomposite Membranes by Electrospinning and Its VOCs Absorption Capacity from Air

    PubMed Central

    Ge, Jun Cong; Choi, Nag Jung

    2017-01-01

    Volatile organic compounds (VOCs) are a source of air pollution and are harmful to both human health and the environment. In this study, we fabricated polyurethane/rare earth (PU/RE) composite nanofibrous membranes via electrospinning with the aim of removing VOCs from air. The morphological structure of PU/RE nanofibrous mats was investigated using field emission scanning electron microscopy (FE-SEM), fourier transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD) experimental analyses. A certain amount of RE (up to 50 wt. % compared to PU pellets) nanoparticles (NPs) could be loaded on/into PU fibers. The tensile strength of PU/RE nanofibrous membranes decreased slightly with the increasing RE powder content. The PU nanofiber containing 50 wt. % RE powder had the smallest fiber diameter of 356 nm; it also showed the highest VOC absorption capacity compared with other composite membranes, having an absorption capacity about three times greater than pure PU nanofibers. In addition, all of the PU/RE nanofibrous membranes readily absorbed styrene the most, followed by xylene, toluene, benzene and chloroform. Therefore, the PU/RE nanofibrous membrane can play an important role in removing VOCs from the air, and its development prospects are impressive because they are emerging materials. PMID:28336894

  11. Development of a solar-powered residential air conditioner. Program review

    NASA Technical Reports Server (NTRS)

    1975-01-01

    Progress in the effort to develop a residential solar-powered air conditioning system is reported. The topics covered include the objectives, scope and status of the program. The results of state-of-art, design, and economic studies and component and system data are also presented.

  12. Photoacoustic and filter measurements related to aerosol light absorption during the Northern Front Range Air Quality Study (Colorado 1996/1997)

    NASA Astrophysics Data System (ADS)

    Moosmüller, H.; Arnott, W. P.; Rogers, C. F.; Chow, J. C.; Frazier, C. A.; Sherman, L. E.; Dietrich, D. L.

    1998-11-01

    A new photoacoustic instrument for the measurement of aerosol light absorption was collocated with conventional aerosol instrumentation during the 1996-1997 winter intensive monitoring period of the Northern Front Range Air Quality Study. Measurements of the light absorption efficiency for black carbon were 5 m2/g at 685 nm and 10 m2/g at 532 nm, and for elemental carbon, they were 3.6 m2/g at 685 nm. We show that these values together with previous photoacoustic measurements of aerosol light absorption shed some light on the wavelength dependence of absorption efficiency for carbonaceous aerosol in the visible and near-visible region. Integrating plate type filter measurements of aerosol light absorption result in far larger values than those measured with the photoacoustic instrument. We demonstrate that a recently published correction technique [Horvath, 1997] can yield improved agreement.

  13. Acaroid mite allergens from the filters of air-conditioning system in China.

    PubMed

    Li, Chao-Pin; Guo, Wei; Zhan, Xiao-Dong; Zhao, Bei-Bei; Diao, Ji-Dong; Li, Na; He, Lian-Ping

    2014-01-01

    Accumulation of acaroid mites in the filters of air-conditioners is harmful to human health. It is important to clarify the allergen components of mites from the filters of local air-conditioning system. The present study was to detect the allergen types in the filters of air-conditioners and assesse their allergenicity by asthmatic models. Sixty aliquots of dust samples were collected from air conditioning filters in civil houses in Wuhu area. Total protein was extracted from the dust samples using PBS and quantified by Bradford method. Allergens I and II were also detected by Western blot using primary antibody (anti-Der f1/2, Der p1/Der f2/Der p2, respectively). Ten aliquots of the positive samples were randomly selected for homogenization and sensitized the mice for developing asthmatic animal models. Total serum IgE level and IFN-γ, IL-4 and IL-5 in the bronchoalveolar lavage fluid (BALF). The allergenicity of the extraction was assessed using pathological sections developed from the mouse pulmonary tissues. The concentration of extract from the 60 samples was ranged from 4.37 μg/ml to 30.76 μg/ml. After analyzing with Western blot, 31 of 60 samples were positive for 4 allergens of acaroid mites, and yet 16 were negative. The levels of total IgE from serum IL-4 and IL-5 from the BALF in the experimental group were apparently higher than that of negative control and PBS group (P < 0.01), but there were no statistical difference compared to OVA group (P > 0.05). However,the IFN-γ level in BALF was lower compared with the negative control and PBS group (P < 0.05) but with the OVA group (P > 0.05). The pathological changes were evidently emerged in pulmonary tissues, which were similar to those of OVA group, compared with the PBS ground and negative controls. The air-conditioner filters in human dwellings of Wuhu area potentially contain the major group allergen 1 and 2 from D. farinae and D. pteronyssinus, which may be associated with seasonal prevalence of

  14. Acaroid mite allergens from the filters of air-conditioning system in China

    PubMed Central

    Li, Chao-Pin; Guo, Wei; Zhan, Xiao-Dong; Zhao, Bei-Bei; Diao, Ji-Dong; Li, Na; He, Lian-Ping

    2014-01-01

    Accumulation of acaroid mites in the filters of air-conditioners is harmful to human health. It is important to clarify the allergen components of mites from the filters of local air-conditioning system. The present study was to detect the allergen types in the filters of air-conditioners and assesse their allergenicity by asthmatic models. Sixty aliquots of dust samples were collected from air conditioning filters in civil houses in Wuhu area. Total protein was extracted from the dust samples using PBS and quantified by Bradford method. Allergens I and II were also detected by Western blot using primary antibody (anti-Der f1/2, Der p1/Der f2/Der p2, respectively). Ten aliquots of the positive samples were randomly selected for homogenization and sensitized the mice for developing asthmatic animal models. Total serum IgE level and IFN-γ, IL-4 and IL-5 in the bronchoalveolar lavage fluid (BALF). The allergenicity of the extraction was assessed using pathological sections developed from the mouse pulmonary tissues. The concentration of extract from the 60 samples was ranged from 4.37 μg/ml to 30.76 μg/ml. After analyzing with Western blot, 31 of 60 samples were positive for 4 allergens of acaroid mites, and yet 16 were negative. The levels of total IgE from serum IL-4 and IL-5 from the BALF in the experimental group were apparently higher than that of negative control and PBS group (P < 0.01), but there were no statistical difference compared to OVA group (P > 0.05). However,the IFN-γ level in BALF was lower compared with the negative control and PBS group (P < 0.05) but with the OVA group (P > 0.05). The pathological changes were evidently emerged in pulmonary tissues, which were similar to those of OVA group, compared with the PBS ground and negative controls. The air-conditioner filters in human dwellings of Wuhu area potentially contain the major group allergen 1 and 2 from D. farinae and D. pteronyssinus, which may be associated with seasonal prevalence of

  15. Post-discharge gas composition of a large-gap DBD in humid air by UV-Vis absorption spectroscopy

    NASA Astrophysics Data System (ADS)

    Moiseev, T.; Misra, N. N.; Patil, S.; Cullen, P. J.; Bourke, P.; Keener, K. M.; Mosnier, J. P.

    2014-12-01

    Large gap dielectric barrier discharges (DBD) provide non-thermal, non-equilibrium plasmas that can generate specific gas chemistry with enhanced bactericidal effects when working in humid air. The present study investigates the post-discharge gas composition of such plasmas operated in humid air using UV-Vis (200-800 nm) absorption spectroscopy. Absorbance spectra have been de-convoluted using direct deconvolution and iterative methods and results are correlated to the DBD electrical parameters. The high-voltage (56 and 70 kV rms) DBD plasma generated at 50 Hz frequency in a closed container over a 20 mm gap in air with relative humidity (RH) of 5-70% has been characterized by I-V and capacitive methods. The post-discharge gas composition at each RH is assessed by UV-Vis absorption spectroscopy for plasma exposure times of 15-120 s. The concentration of ozone and nitrogen oxides (O3, NO2, NO3, N2O4) increases with plasma exposure time but a strong decrease in [O3] levels is obtained with increase in RH. The decrease in [O3] and an abundance of nitrogen oxides is ascribed to high specific power densities in the closed container and to increasing RH levels. The absorbance residual following deconvolution shows a strong band at 230-270 nm consistent with the presence of pernitric acid (HNO4) and other HNOx (x = 1, 3) species. Humid air large gap DBD plasmas in closed containers generate along with O3, high levels of nitrogen oxides and HNOx (x = 1, 4) acids leading to increased bactericidal rates.

  16. Vermicompost and biochar as bio-conditioners to immobilize heavy metal and improve soil fertility on cadmium contaminated soil under acid rain stress.

    PubMed

    Wang, Ying; Xu, YongAn; Li, Dan; Tang, BiCong; Man, ShuLei; Jia, YiFan; Xu, Heng

    2018-04-15

    This experiment was conducted to investigate the remediation effects of bio-conditioners vermicompost (VC) and biochar (BC) on cadmium contaminated soil under the threat of acid rain, individually and associatively. With the application of soil conditioners, the percentages of HOAc-extractable Cd decreased 5.2-6.8%, 9.0-13.5% and 7.9-12.1% in the groups amended with VC, BC and VC combined BC, respectively. When the pH of rain decreased from 7.0 to 4.0, the activity of acid phosphatase decreased 2.0%, 12.3%, 3.2%, 14.8% in VC, BC, VC combined BC and control groups, individually. This study affirmed that with the application of soil conditioners, the threat of heavy metal along with bioavailability of Cd was depressed, and the properties of soil biochemical indictors were enhanced. Oppositely, the bioavailability of Cd was promoted, and soil microbial viability as well as nutrient contents was inhibited with the spraying of acid rain. The findings indicated that acid deposition played a restrain effect on soil remediation process. Meanwhile, soil conditioners showed potentials to improve soil fertilities and alleviate the stress of acid rain. Copyright © 2017. Published by Elsevier B.V.

  17. Desiccant-assisted air conditioner improves IAQ and comfort

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Meckler, M.

    1994-10-01

    This article describes a system which offers the advantage of downsizing the evaporator coil and condensing unit capacities for comparable design loads, which in turn provides numerous benefits. Airborne microorganisms, which are responsible for many acute diseases, infections, and allergies, are well protected indoors by the moisture surrounding them. While the human body is generally the host for various bacteria and viruses, fungi can grow in moist places. It has been concluded that an optimum relative humidity (RH) range of 40 to 60 percent is necessary to minimize or eliminate the bacterial, viral, and fungal growth. In addition, humidity alsomore » has an effect on air cleanliness--it reduces the presence of dust particles--and on the deterioration of the building structure and its contents. Therefore, controlling humidity is a very important factor to human comfort in minimizing adverse health effects and maximizing the structural longevity of the building.« less

  18. Air Force Academy Aeronautics Digest - Fall/Winter 1981.

    DTIC Science & Technology

    1982-06-01

    After all, some guy just peddled across the English Channel?!" In reply wo cite Professor E.S. Taylor , who, in a wonderfully readable article (Ref...to the cadet wing, Spring, 1976. 2. Taylor , Edward S., "Evolution of the Jet Engine," Astronautics and Aeronautics, November 1970, pps. 64-72. 3...heat pump, air conditioner, or refrigerator. The Brayton cycle is the cycle that is used by a turbojet or turbofan engine. We have some fine engine test

  19. Development of polyvinylether refrigeration oil for hydrofluorocarbon air-conditioning systems

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Tozaki, Toshinori; Konishi, Tsuneo; Nagamatsu, Noritoshi

    1998-10-01

    Polyolestor (POE) poses capillary tube blockage problems when it is used as an air-conditioner refrigeration oil. A polyvinylether (PVE) oil has been developed to settle such problems. The causes of blockage were determined by analyzing capillary tubes after testing them with PVE and POE in the laboratory and in actual equipment. PVE was confirmed to have superior performance over POE with respect to resistance of capillary tube blockage.

  20. Solar Powered Liquid Desiccant Air Conditioner for Low-Electricity Humidity Control

    DTIC Science & Technology

    2012-07-01

    thermal comfort conditions. Liquid-desiccants are solutions that are hygroscopic but are easily able to be pumped and applied within heating, ventilating, and air conditioning (HVAC) equipment as necessary.

  1. Sound absorption by clamped poroelastic plates.

    PubMed

    Aygun, H; Attenborough, K

    2008-09-01

    Measurements and predictions have been made of the absorption coefficient and the surface acoustic impedance of poroelastic plates clamped in a large impedance tube and separated from the rigid termination by an air gap. The measured and predicted absorption coefficient and surface impedance spectra exhibit low frequency peaks. The peak frequencies observed in the absorption coefficient are close to those predicted and measured in the deflection spectra of the clamped poroelastic plates. The influences of the rigidity of the clamping conditions and the width of the air gap have been investigated. Both influences are found to be important. Increasing the rigidity of clamping reduces the low frequency absorption peaks compared with those measured for simply supported plates or plates in an intermediate clamping condition. Results for a closed cell foam plate and for two open cell foam plates made from recycled materials are presented. For identical clamping conditions and width of air gap, the results for the different materials differ as a consequence mainly of their different elasticity, thickness, and cell structure.

  2. Impacts of the Degradation of 2,3,3,3-Tetrafluoropropene into Trifluoroacetic Acid from Its Application in Automobile Air Conditioners in China, the United States, and Europe.

    PubMed

    Wang, Ziyuan; Wang, Yuhang; Li, Jianfeng; Henne, Stephan; Zhang, Boya; Hu, Jianxin; Zhang, Jianbo

    2018-03-06

    HFO-1234yf (2,3,3,3-tetrafluoropropene) was proposed as an automobile air conditioner (MAC) refrigerant worldwide. However, its atmospheric degradation product is the highly soluble and phytotoxic trifluoroacetic acid (TFA), which persists in aquatic environments. We used a global three-dimensional chemical transport model to assess the potential environmental effects resulting from complete future conversion of the refrigerant in all MAC to HFO-1234yf in China, the United States, and Europe. The annual mean atmospheric concentrations of HFO-1234yf were 2.62, 2.20, and 2.73 pptv, and the mean deposition rates of TFA were 0.96, 0.45, and 0.52 kg km -2 yr -1 , in three regions. The regional TFA deposition sources mainly came from emissions within the same region. The annual TFA deposition in the North Pole region was lower than the global average and mainly originated from European emissions. A potential doubling in the future HFO-1234yf emissions in China mainly affected the local TFA depositions. The TFA concentrations in rainwater were strongly affected by the regional precipitation rates. North Africa and the Middle East, regions with scant rainfall, had extremely high TFA concentrations. The rainwater concentrations of TFA during individual rain events can exceed the level considered to be safe, indicating substantial potential regional risks from future HFO-1234yf use.

  3. Relationship between Fear Conditionability and Aversive Memories: Evidence from a Novel Conditioned-Intrusion Paradigm

    PubMed Central

    Wegerer, Melanie; Blechert, Jens; Kerschbaum, Hubert; Wilhelm, Frank H.

    2013-01-01

    Intrusive memories – a hallmark symptom of posttraumatic stress disorder (PTSD) – are often triggered by stimuli possessing similarity with cues that predicted or accompanied the traumatic event. According to learning theories, intrusive memories can be seen as a conditioned response to trauma reminders. However, direct laboratory evidence for the link between fear conditionability and intrusive memories is missing. Furthermore, fear conditioning studies have predominantly relied on standardized aversive stimuli (e.g. electric stimulation) that bear little resemblance to typical traumatic events. To investigate the general relationship between fear conditionability and aversive memories, we tested 66 mentally healthy females in a novel conditioned-intrusion paradigm designed to model real-life traumatic experiences. The paradigm included a differential fear conditioning procedure with neutral sounds as conditioned stimuli and short violent film clips as unconditioned stimuli. Subsequent aversive memories were assessed through a memory triggering task (within 30 minutes, in the laboratory) and ambulatory assessment (involuntary aversive memories in the 2 days following the experiment). Skin conductance responses and subjective ratings demonstrated successful differential conditioning indicating that naturalistic aversive film stimuli can be used in a fear conditioning experiment. Furthermore, aversive memories were elicited in response to the conditioned stimuli during the memory triggering task and also occurred in the 2 days following the experiment. Importantly, participants who displayed higher conditionability showed more aversive memories during the memory triggering task and during ambulatory assessment. This suggests that fear conditioning constitutes an important source of persistent aversive memories. Implications for PTSD and its treatment are discussed. PMID:24244407

  4. Ammonia removal from landfill leachate by air stripping and absorption.

    PubMed

    Ferraz, Fernanda M; Povinelli, Jurandyr; Vieira, Eny Maria

    2013-01-01

    An old landfill leachate was pre-treated in a pilot-scale aerated packed tower operated in batch mode for total ammoniacal nitrogen (TAN) removal. The stripped ammonia was recovered with a 0.4 mol L(-1) H2SO4 solution, deionized water and tap water. Ca(OH)2 (95% purity) or commercial hydrated lime was added to the raw leachate to adjust its pH to 11, causing removal of colour (82%) and heavy metals (70-90% for Zn, Fe and Mn). The 0.4 molL(-1) H2SO4 solution was able to neutralize 80% of the stripped ammonia removed from 12 L of leachate. The effectiveness of the neutralization of ammonia with deionized water was 75%. Treating 100 L of leachate, the air stripping tower removed 88% of TAN after 72 h of aeration, and 87% of the stripped ammonia was recovered in two 31 L pilot-scale absorption units filled with 20 L of tap water.

  5. Determination of Spatial Distribution of Air Pollution by Dye Laser Measurement of Differential Absorption of Elastic Backscatter

    NASA Technical Reports Server (NTRS)

    Ahmed, S. A.; Gergely, J. S.

    1973-01-01

    This paper presents the results of an analytical study of a lidar system which uses tunable organic dye lasers to accurately determine spatial distribution of molecular air pollutants. Also described will be experimental work to date on simultaneous multiwavelength output dye laser sources for this system. Basically the scheme determines the concentration of air pollutants by measuring the differential absorption of an (at least) two wavelength lidar signal elastically backscattered by the atmosphere. Only relative measurements of the backscattered intensity at each of the two wavelengths, one on and one off the resonance absorption of the pollutant in question, are required. The various parameters of the scheme are examined and the component elements required for a system of this type discussed, with emphasis on the dye laser source. Potential advantages of simultaneous multiwavelength outputs are described. The use of correlation spectroscopy in this context is examined. Comparisons are also made for the use of infrared probing wavelengths and sources instead of dye lasers. Estimates of the sensitivity and accuracy of a practical dye laser system of this type, made for specific pollutants, snow it to have inherent advantages over other schemes for determining pollutant spatial distribution.

  6. Preliminary design package for residential heating/cooling system: Rankine air conditioner redesign

    NASA Technical Reports Server (NTRS)

    1978-01-01

    A summary of the preliminary redesign and development of a marketable single family heating and cooling system is presented. The interim design and schedule status of the residential (3-ton) redesign, problem areas and solutions, and the definition of plans for future design and development activities were discussed. The proposed system for a single-family residential heating and cooling system is a single-loop, solar-assisted, hydronic-to-warm-air heating subsystem with solar-assisted domestic water heating and a Rankine-driven expansion air-conditioning subsystem.

  7. Design of Interline Unified Power Quality Conditioner for Power Quality Disturbances using Simulink

    NASA Astrophysics Data System (ADS)

    Kumaraswamy, G.; Reddy, Y. Rajasekhar; Harikrishna, Ch.

    2012-10-01

    Proliferation of electronic equipment in commercial and industrial processes has resulted in increasingly sensitive electrical loads to be fed from power distribution system which introduce contamination to voltage and current waveforms at the point of common coupling of industrial loads. The unified power quality conditioner (UPQC) is connected between two different feeders (lines), hence this method of connection of the UPQC is called as Interline UPQC (IUPQC).This paper proposes a new connection for a UPQC to improve the power quality of two feeders in a distribution system. Interline Unified Power Quality Conditioner (IUPQC), specifically aims at the integration of series VSC and Shunt VSC to provide high quality power supply by means of voltage sag/swell compensation, harmonic elimination and power factor correction in a power distribution network, so that improved power quality can be made available at the point of common coupling. The structure, control and capability of the IUPQC are discussed in this paper. The efficiency of the proposed configuration has been verified through simulation using MATLAB/ SIMULINK.

  8. 24 CFR 3285.503 - Optional appliances.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... installation instructions. (1) Air conditioners. Air conditioning equipment must be listed or certified by a... instructions. (B) The air conditioner manufacturer instructions must be followed. (C) All condensation must be... efficiency. (A) Site-installed central air conditioning equipment must be sized to meet the home's heat gain...

  9. 24 CFR 3285.503 - Optional appliances.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... installation instructions. (1) Air conditioners. Air conditioning equipment must be listed or certified by a... instructions. (B) The air conditioner manufacturer instructions must be followed. (C) All condensation must be... efficiency. (A) Site-installed central air conditioning equipment must be sized to meet the home's heat gain...

  10. Performance of a biogas upgrading process based on alkali absorption with regeneration using air pollution control residues.

    PubMed

    Baciocchi, Renato; Carnevale, Ennio; Costa, Giulia; Gavasci, Renato; Lombardi, Lidia; Olivieri, Tommaso; Zanchi, Laura; Zingaretti, Daniela

    2013-12-01

    This work analyzes the performance of an innovative biogas upgrading method, Alkali absorption with Regeneration (AwR) that employs industrial residues and allows to permanently store the separated CO2. This process consists in a first stage in which CO2 is removed from the biogas by means of chemical absorption with KOH or NaOH solutions followed by a second stage in which the spent absorption solution is contacted with waste incineration Air Pollution Control (APC) residues. The latter reaction leads to the regeneration of the alkali reagent in the solution and to the precipitation of calcium carbonate and hence allows to reuse the regenerated solution in the absorption process and to permanently store the separated CO2 in solid form. In addition, the final solid product is characterized by an improved environmental behavior compared to the untreated residues. In this paper the results obtained by AwR tests carried out in purposely designed demonstrative units installed in a landfill site are presented and discussed with the aim of verifying the feasibility of this process at pilot-scale and of identifying the conditions that allow to achieve all of the goals targeted by the proposed treatment. Specifically, the CO2 removal efficiency achieved in the absorption stage, the yield of alkali regeneration and CO2 uptake resulting for the regeneration stage, as well as the leaching behavior of the solid product are analyzed as a function of the type and concentration of the alkali reagent employed for the absorption reaction. Copyright © 2013 Elsevier Ltd. All rights reserved.

  11. DEVELOPMENT OF A LINEAR COMPRESSOR FOR AIR CONDITIONERS AND HEAT PUMPS

    EPA Science Inventory

    The report discusses the design, building, testing, and delivering to the Environmental Protection Agency of a linear compressor for operation in a 3.0- ton (10.5 kW) residential air-conditioning and heat pumping system. The compressor design evolved from a linear resonant piston...

  12. 48 CFR 23.804 - Contract clauses.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... refrigerant, such as air conditioners, including motor vehicles, refrigerators, chillers, or freezers. [61 FR... Equipment and Air Conditioners, in solicitations and contracts for services when the contract includes the...

  13. Candidate chemical systems for air cooled solar powered, absorption air conditioner design. Part I. Organic absorbent systems

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Biermann, W. J.

    1978-01-01

    All the available experimental evidence suggests that the optimum ''organic'' absorbent/refrigerant combination would be a methane derivative with a single hydrogen atom with chlorine and fluorine atoms in the other sites, as refrigerant. This would be hydrogen bonded to an absorbent molecule containing the group =NC/sup -/O, with the substituent groups being such that no steric hindrance took place. Cycle analyses showed that the ratio of internal heat transfer to cooling would be large, probably impractically so in view of the high coefficient of performance needed for solar driven cooling and the additional handicap of heat rejection to the atmosphere.more » A more promising approach would be to reduce the internal heat transfer per unit of space cooling by selecting a refrigerant with a high latent heat of vaporization and selecting an absorbent with suitable properties.« less

  14. Desiccant Enhanced Evaporative Air-Conditioning (DEVap): Evaluation of a New Concept in Ultra Efficient Air Conditioning

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Kozubal, E.; Woods, J.; Burch, J.

    2011-01-01

    NREL has developed the novel concept of a desiccant enhanced evaporative air conditioner (DEVap) with the objective of combining the benefits of liquid desiccant and evaporative cooling technologies into an innovative 'cooling core.' Liquid desiccant technologies have extraordinary dehumidification potential, but require an efficient cooling sink. DEVap's thermodynamic potential overcomes many shortcomings of standard refrigeration-based direct expansion cooling. DEVap decouples cooling and dehumidification performance, which results in independent temperature and humidity control. The energy input is largely switched away from electricity to low-grade thermal energy that can be sourced from fuels such as natural gas, waste heat, solar, or biofuels.

  15. Remote Sensing Global Surface Air Pressure Using Differential Absorption BArometric Radar (DiBAR)

    NASA Technical Reports Server (NTRS)

    Lin, Bing; Harrah, Steven; Lawrence, Wes; Hu, Yongxiang; Min, Qilong

    2016-01-01

    Tropical storms and severe weathers are listed as one of core events that need improved observations and predictions in World Meteorological Organization and NASA Decadal Survey (DS) documents and have major impacts on public safety and national security. This effort tries to observe surface air pressure, especially over open seas, from space using a Differential-absorption BArometric Radar (DiBAR) operating at the 50-55 gigahertz O2 absorption band. Air pressure is among the most important variables that affect atmospheric dynamics, and currently can only be measured by limited in-situ observations over oceans. Analyses show that with the proposed space radar the errors in instantaneous (averaged) pressure estimates can be as low as approximately 4 millibars (approximately 1 millibar under all weather conditions). With these sea level pressure measurements, the forecasts of severe weathers such as hurricanes will be significantly improved. Since the development of the DiBAR concept about a decade ago, NASA Langley DiBAR research team has made substantial progress in advancing the concept. The feasibility assessment clearly shows the potential of sea surface barometry using existing radar technologies. The team has developed a DiBAR system design, fabricated a Prototype-DiBAR (P-DiBAR) for proof-of-concept, conducted lab, ground and airborne P-DiBAR tests. The flight test results are consistent with the instrumentation goals. Observational system simulation experiments for space DiBAR performance based on the existing DiBAR technology and capability show substantial improvements in tropical storm predictions, not only for the hurricane track and position but also for the hurricane intensity. DiBAR measurements will lead us to an unprecedented level of the prediction and knowledge on global extreme weather and climate conditions.

  16. Response of microbial community of organic-matter-impoverished arable soil to long-term application of soil conditioner derived from dynamic rapid fermentation of food waste

    PubMed Central

    Hou, Jiaqi; Li, Mingxiao; Mao, Xuhui; Hao, Yan; Ding, Jie; Liu, Dongming; Liu, Hongliang

    2017-01-01

    Rapid fermentation of food waste can be used to prepare soil conditioner. This process consumes less time and is more cost-effective than traditional preparation technology. However, the succession of the soil microbial community structure after long-term application of rapid fermentation-derived soil conditioners remains unclear. Herein, dynamic rapid fermentation (DRF) of food waste was performed to develop a soil conditioner and the successions and diversity of bacterial communities in an organic-matter-impoverished arable soil after six years of application of DRF-derived soil conditioner were investigated. Results showed that the treatment increased soil organic matter (SOM) accumulation and strawberry yield by 5.3 g/kg and 555.91 kg/ha, respectively. Proteobacteria, Actinobacteria, Acidobacteria, and Firmicutes became the dominant phyla, occupying 65.95%–77.52% of the bacterial sequences. Principal component analysis (PCA) results showed that the soil bacterial communities were largely influenced by the treatment. Redundancy analysis (RDA) results showed that the relative abundances of Gemmatimonadetes, Chloroflexi, Verrucomicrobia, Nitrospirae, and Firmicutes were significantly correlated with soil TC, TN, TP, NH4+-N, NO3−-N, OM, and moisture. These communities were all distributed in the soil samples collected in the sixth year of application. Long-term treatment did not enhance the diversity of bacterial species but significantly altered the distribution of major functional bacterial communities in the soils. Application of DRF-derived soil conditioner could improve the soil quality and optimize the microbial community, ultimately enhancing fruit yields. PMID:28419163

  17. Response of microbial community of organic-matter-impoverished arable soil to long-term application of soil conditioner derived from dynamic rapid fermentation of food waste.

    PubMed

    Hou, Jiaqi; Li, Mingxiao; Mao, Xuhui; Hao, Yan; Ding, Jie; Liu, Dongming; Xi, Beidou; Liu, Hongliang

    2017-01-01

    Rapid fermentation of food waste can be used to prepare soil conditioner. This process consumes less time and is more cost-effective than traditional preparation technology. However, the succession of the soil microbial community structure after long-term application of rapid fermentation-derived soil conditioners remains unclear. Herein, dynamic rapid fermentation (DRF) of food waste was performed to develop a soil conditioner and the successions and diversity of bacterial communities in an organic-matter-impoverished arable soil after six years of application of DRF-derived soil conditioner were investigated. Results showed that the treatment increased soil organic matter (SOM) accumulation and strawberry yield by 5.3 g/kg and 555.91 kg/ha, respectively. Proteobacteria, Actinobacteria, Acidobacteria, and Firmicutes became the dominant phyla, occupying 65.95%-77.52% of the bacterial sequences. Principal component analysis (PCA) results showed that the soil bacterial communities were largely influenced by the treatment. Redundancy analysis (RDA) results showed that the relative abundances of Gemmatimonadetes, Chloroflexi, Verrucomicrobia, Nitrospirae, and Firmicutes were significantly correlated with soil TC, TN, TP, NH4+-N, NO3--N, OM, and moisture. These communities were all distributed in the soil samples collected in the sixth year of application. Long-term treatment did not enhance the diversity of bacterial species but significantly altered the distribution of major functional bacterial communities in the soils. Application of DRF-derived soil conditioner could improve the soil quality and optimize the microbial community, ultimately enhancing fruit yields.

  18. Evaluation of rotor-bearing system dynamic response to unbalance. [air conditioning equipment

    NASA Technical Reports Server (NTRS)

    Thaller, R. E.; Ozimek, D. W.

    1979-01-01

    The vibration environment within air conditioner rotating machinery referred to as an air cycle machine (ACM) was investigated to effectively increase ACM reliability. To assist in the selection of design changes which would result in improved ACM performance, various design modifications were incorporated into a baseline ACM configuration. For each design change, testing was conducted with the best balance achieveable (baseline) and with various degrees of unbalance. Relationships between unbalance (within the context of design changes) and the parameters associated with design goals were established. The results of rotor dynamics tests used to establish these relationships are presented.

  19. Application of support vector machine method for the analysis of absorption spectra of exhaled air of patients with broncho-pulmonary diseases

    NASA Astrophysics Data System (ADS)

    Bukreeva, Ekaterina B.; Bulanova, Anna A.; Kistenev, Yury V.; Kuzmin, Dmitry A.; Tuzikov, Sergei A.; Yumov, Evgeny L.

    2014-11-01

    The results of the joint use of laser photoacoustic spectroscopy and chemometrics methods in gas analysis of exhaled air of patients with respiratory diseases (chronic obstructive pulmonary disease, pneumonia and lung cancer) are presented. The absorption spectra of exhaled breath of all volunteers were measured, the classification methods of the scans of the absorption spectra were applied, the sensitivity/specificity of the classification results were determined. It were obtained a result of nosological in pairs classification for all investigated volunteers, indices of sensitivity and specificity.

  20. 10 CFR 431.91 - Purpose and scope.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... EQUIPMENT Commercial Air Conditioners and Heat Pumps § 431.91 Purpose and scope. This subpart specifies test procedures and energy conservation standards for certain commercial air conditioners and heat pumps, pursuant...

  1. 10 CFR 431.91 - Purpose and scope.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... EQUIPMENT Commercial Air Conditioners and Heat Pumps § 431.91 Purpose and scope. This subpart specifies test procedures and energy conservation standards for certain commercial air conditioners and heat pumps, pursuant...

  2. 10 CFR 431.91 - Purpose and scope.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... EQUIPMENT Commercial Air Conditioners and Heat Pumps § 431.91 Purpose and scope. This subpart specifies test procedures and energy conservation standards for certain commercial air conditioners and heat pumps, pursuant...

  3. 10 CFR 431.91 - Purpose and scope.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... EQUIPMENT Commercial Air Conditioners and Heat Pumps § 431.91 Purpose and scope. This subpart specifies test procedures and energy conservation standards for certain commercial air conditioners and heat pumps, pursuant...

  4. 10 CFR 431.91 - Purpose and scope.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... EQUIPMENT Commercial Air Conditioners and Heat Pumps § 431.91 Purpose and scope. This subpart specifies test procedures and energy conservation standards for certain commercial air conditioners and heat pumps, pursuant...

  5. Resources and Fact Sheets on Servicing Motor Vehicle Air Conditioners (Summary Page)

    EPA Pesticide Factsheets

    Page provides links to resources that can assist motor vehicle air-conditioning system technicians in understanding system servicing requirements and best practices, and learn about alternative refrigerants.

  6. 40 CFR 1066.801 - Applicability and general provisions.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... emission effects from aggressive driving and operation with the vehicle's air conditioner. The SFTP is... driving schedule represents about 3.6 miles of urban driving with the air conditioner operating; and the.... 1066.801 Section 1066.801 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR...

  7. Effects of conditioners on microshear bond strength to enamel after carbamide peroxide bleaching and/or casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) treatment.

    PubMed

    Adebayo, O A; Burrow, M F; Tyas, M J

    2007-11-01

    To evaluate (a) the enamel microshear bond strength (MSBS) of a universal adhesive and (b) the effects of conditioning with a self-etching primer adhesive with/without prior bleaching and/or casein phosphopeptide-amorphous calcium phosphate (CPP-ACP) application. Thirty-five molars were cut into four sections, assigned randomly to four groups (no treatment; 16% carbamide peroxide bleaching; CPP-ACP-containing paste (Tooth Mousse, TM); bleaching and TM) and treated accordingly. Specimens were divided into two for bonding with either a self-etching primer (Clearfil SE Bond, CSE) or a total-etch adhesive (Single Bond, SB). Specimens for CSE bonding were subdivided for one of four preconditioning treatments (no conditioning; 30-40% phosphoric acid (PA); 15% EDTA; 20% polyacrylic acid conditioner (Cavity conditioner, CC) and treated. The adhesives were applied and resin composite bonded to the enamel using microtubes (internal diameter 0.75mm). Bonds were stressed in shear until failure, mean MSBS calculated and data analysed using ANOVA with Tukey's HSD test (alpha=0.05). The modes of bond failure were assessed and classified. Two-way ANOVA revealed significant differences between treatments (P<0.0001), conditioners (P<0.0001) and a significant interaction between treatments and conditioners (P=0.001). One-way ANOVA revealed no significant differences in MSBS following any of the treatments for SB; following TM application for CSE without preconditioning; and significant differences in MSBS following bleaching with and without TM application for CSE. With preconditioning, applying PA before CSE post-bleaching and either PA or CC before CSE post-TM application, resulted in significant differences in MSBS (P<0.05). The use of conditioners prior to bonding with the self-etching primer adhesive system on treated enamel may significantly improve bond strengths.

  8. 78 FR 14024 - Energy Efficiency Program for Commercial and Industrial Equipment: Public Meeting and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-04

    ...: Public Meeting and Availability of the Framework Document for Packaged Terminal Air Conditioners and... document for packaged terminal air conditioners and heat pumps. This notice corrects the date of the public... announcement of a public meeting and availability of the framework document for packaged terminal air...

  9. Aerosol Absorption by Black Carbon and Dust: Implications of Climate Change and Air Quality in Asia

    NASA Technical Reports Server (NTRS)

    Chin, Mian

    2010-01-01

    Atmospheric aerosol distributions from 2000 to 2007 are simulated with the global model GOCART to attribute light absorption by aerosol to its composition and sources. We show the seasonal and interannual variations of absorbing aerosols in the atmosphere over Asia, mainly black carbon and dust. and their linkage to the changes of anthropogenic and dust emissions in the region. We compare our results with observations from satellite and ground-based networks, and estimate the importance of black carbon and dust on regional climate forcing and air quality.

  10. United States Air Force Weapons Laboratory Research Scholar Program, 1983-1984.

    DTIC Science & Technology

    1984-10-01

    voltage upon passing through an RC circuit .) The phase shift is given by = tan-Tf (3) * where T is the cavity lifetime and f is the modulation ...spark in air at the external terminals of a filter module has * S. . . . . .. S ** . * * * * Page 8-18 approximately the same effect on the circuit as a... module usually contains a metal oxide varistor(s), and perhaps also 3 an RFI filter circuit . We shall discuss line conditioners and surge protection

  11. 76 FR 19913 - Compliance Testing Procedures: Correction Factor for Room Air Conditioners

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-11

    ... covered under ASHRAE Standard 37, generally do not have this feature and operate primarily with dry... performance. It is the air mass flow rate that transfers heat between cooler coils or condensers and...

  12. Effect of different cavity conditioners on microleakage of glass ionomer cement with a high viscosity in primary teeth

    PubMed Central

    Mazaheri, Romina; Pishevar, Leila; Shichani, Ava Vali; Geravandi, Sanas

    2015-01-01

    Background: Glass ionomer cement is a common material used in pediatric dentistry. The aim of this study was to evaluate the microleakage of high-viscosity glass ionomer restorations in deciduous teeth after conditioning with four different conditioners. Materials and Methods: Fifty intact primary canines were collected. Standard Class V cavities (2 mm × 1.5 mm × 3 mm) were prepared by one operator on all buccal tooth surfaces, including both enamel and dentin. The samples were divided into five groups with different conditioners (no conditioner, 20% acrylic acid, 35% phosphoric acid, 12% citric acid, and 17% ethylenediaminetetraacetic acid [EDTA]). Two-way — ANOVA, Kruskal–Wallis and Mann–Whitney tests were used to compare the means of microleakage between the five groups. The significance level was set at P < 0.05. Results: There was no significant difference between the means of microleakage in incisal (enamel) and gingival (dentin) margins (P = 0.34). Furthermore, there was no significant difference between the means of microleakage in enamel and dentin margins (P = 0.4). There was a significant difference between the means of microleakage in different groups (P = 0.03). Conclusion: Within the limitations of this study, it is suggested that 20% acrylic acid and 17% EDTA be used for cavity conditioning which can result in better chemical and micromechanical adhesion. PMID:26288623

  13. Thin structured rigid body for acoustic absorption

    NASA Astrophysics Data System (ADS)

    Starkey, T. A.; Smith, J. D.; Hibbins, A. P.; Sambles, J. R.; Rance, H. J.

    2017-01-01

    We present a thin acoustic metamaterial absorber, comprised of only rigid metal and air, that gives rise to near unity absorption of airborne sound on resonance. This simple, easily fabricated, robust structure comprising a perforated metal plate separated from a rigid wall by a deeply subwavelength channel of air is an ideal candidate for a sound absorbing panel. The strong absorption in the system is attributed to the thermo-viscous losses arising from a sound wave guided between the plate and the wall, defining the subwavelength channel.

  14. Fetal death of dogs after the ingestion of a soil conditioner.

    PubMed

    Hong, Il-Hwa; Kwon, Tae-Eog; Lee, Seung-Keun; Park, Jin-Kyu; Ki, Mi-Ran; Park, Se-Il; Jeong, Kyu-Shik

    2011-01-01

    Castor beans (Ricinus communis) contain ricin, which is one of the most toxic substances of plant origin. Ricin toxicosis has been reported in different countries with usually ingestion of castor beans or plants in both animals and humans. However, ricin toxicosis by ingestion of some products containing castor oil cake has rarely been reported. This paper describes outbreaks of dog death by ricin toxicosis after accidental ingestion of the same soil conditioner. Fifteen dogs showed toxic symptoms such as severe vomiting, abdominal pain and hemorrhagic diarrhea, and then thirteen dogs died in a few days. The soil conditioner dogs ingested consisted of 10% castor oil cake containing ricin. On the basis of clinical signs, laboratory and pathologic findings, a diagnosis of ricin toxicosis was established in the present case. In comparison with previous cases by ingestion of castor beans, the dogs' morbidity was very high in the present case. The ingestion of castor oil cake may be more dangerous to life than the castor beans. It is because mortality by ingestion of castor beans depends on the degree of mastication of the beans, whereas ricin in oil cake is easily absorbed from the stomach and the intestines. As ricin is a heat-labile toxin, products containing ricin or oil cake should be properly treated with heat and have written caution sentences about toxicosis, and be kept out of reach of domestic animals and children. Copyright © 2009 Elsevier GmbH. All rights reserved.

  15. Optimization of absorption air-conditioning for solar energy applications

    NASA Technical Reports Server (NTRS)

    Perry, E. H.

    1976-01-01

    Improved performance of solar cooling systems using the lithium bromide water absorption cycle is investigated. Included are computer simulations of a solar-cooled house, analyses and measurements of heat transfer rates in absorption system components, and design and fabrication of various system components. A survey of solar collector convection suppression methods is presented.

  16. Visual Aspects of the Electric Environment. NECA Electrical Design Guidelines.

    ERIC Educational Resources Information Center

    National Electrical Contractors Association, Washington, DC.

    New design opportunities afforded by modern high-intensity light sources, and the many ways of integrating package air-conditioners with the design of buildings, are discussed. A guide to unitary air-conditioners and heat pumps is included. (RK)

  17. Assessment of commercially available energy-efficient room air conditioners including models with low global warming potential (GWP) refrigerants

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Shah, N. K.; Park, W. Y.; Gerke, B.

    Improving the energy efficiency of room air conditioners (RACs) while transitioning to low global-warming-potential (GWP) refrigerants will be a critical step toward reducing the energy, peak load, and emissions impacts of RACs while keeping costs low. Previous research quantified the benefits of leapfrogging to high efficiency in tandem with the transition to low-GWP refrigerants for RACs (Shah et al., 2015) and identified opportunities for initial action to coordinate energy efficiency with refrigerant transition in economies constituting about 65% of the global RAC market (Shah et al., 2017). This report describes further research performed to identify the best-performing (i.e., most efficientmore » and low-GWP-refrigerant using) RACs on the market, to support an understanding of the best available technology (BAT). Understanding BAT can help support market-transformation programs for high-efficiency and low-GWP equipment such as minimum energy performance standards (MEPS), labeling, procurement, and incentive programs. We studied RACs available in six economies—China, Europe, India, Japan, South Korea, and the United States—that together account for about 70% of global RAC demand, as well as other emerging economies. The following are our key findings: • Highly efficient RACs using low-GWP refrigerants, e.g., HFC-32 (R-32) and HC-290 (R-290), are commercially available today at prices comparable to similar RACs using high-GWP HCFC-22 (R-22) or HFC-410A (R-410A). • High efficiency is typically a feature of high-end products. However, highly efficient, cost-competitive (less than 1,000 or 1,500 U.S. dollars in retail price, depending on size) RACs are available. • Where R-22 is being phased out, high GWP R-410A still dominates RAC sales in most mature markets except Japan, where R-32 dominates. • In all of the economies studied except Japan, only a few models are energy efficient and use low-GWP refrigerants. For example, in Europe, India, and

  18. 76 FR 72872 - Rule Concerning Disclosures Regarding Energy Consumption and Water Use of Certain Home Appliances...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-28

    ... standards impose regional efficiency standards for split air conditioners, package air conditioners, and gas.... Specifically, DOE will require nonweatherized gas furnaces to comply by May 1, 2013; and weatherized gas... Dakota, Ohio, Oregon, Pennsylvania, Rhode Island, South Dakota, Utah, Vermont, Washington, West Virginia...

  19. Design and operation of a solar heating and cooling system for a residential size building

    NASA Technical Reports Server (NTRS)

    Littles, J. W.; Humphries, W. R.; Cody, J. C.

    1978-01-01

    The first year of operation of solar house is discussed. Selected design information, together with a brief system description is included. The house was equipped with an integrated solar heating and cooling system which uses fully automated state-of-the art. Evaluation of the data indicate that the solar house heating and cooling system is capable of supplying nearly 100 percent of the thermal energy required for heating and approximately 50 percent of the thermal energy required to operate the absorption cycle air conditioner.

  20. Air change rates of motor vehicles and in-vehicle pollutant concentrations from secondhand smoke.

    PubMed

    Ott, Wayne; Klepeis, Neil; Switzer, Paul

    2008-05-01

    The air change rates of motor vehicles are relevant to the sheltering effect from air pollutants entering from outside a vehicle and also to the interior concentrations from any sources inside its passenger compartment. We made more than 100 air change rate measurements on four motor vehicles under moving and stationary conditions; we also measured the carbon monoxide (CO) and fine particle (PM(2.5)) decay rates from 14 cigarettes smoked inside the vehicle. With the vehicle stationary and the fan off, the ventilation rate in air changes per hour (ACH) was less than 1 h(-1) with the windows closed and increased to 6.5 h(-1) with one window fully opened. The vehicle speed, window position, ventilation system, and air conditioner setting was found to affect the ACH. For closed windows and passive ventilation (fan off and no recirculation), the ACH was linearly related to the vehicle speed over the range from 15 to 72 mph (25 to 116 km h(-1)). With a vehicle moving, windows closed, and the ventilation system off (or the air conditioner set to AC Max), the ACH was less than 6.6 h(-1) for speeds ranging from 20 to 72 mph (32 to 116 km h(-1)). Opening a single window by 3'' (7.6 cm) increased the ACH by 8-16 times. For the 14 cigarettes smoked in vehicles, the deposition rate k and the air change rate a were correlated, following the equation k=1.3a (R(2)=82%; n=14). With recirculation on (or AC Max) and closed windows, the interior PM(2.5) concentration exceeded 2000 microg m(-3) momentarily for all cigarettes tested, regardless of speed. The concentration time series measured inside the vehicle followed the mathematical solutions of the indoor mass balance model, and the 24-h average personal exposure to PM(2.5) could exceed 35 microg m(-3) for just two cigarettes smoked inside the vehicle.

  1. 75 FR 62122 - Energy Conservation Program for Certain Industrial Equipment: Publication of the Petition for...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-10-07

    ... rating the Altherma products in Europe. The test procedures are EN 14511 ``Air conditioners, liquid chilling packages and heat pumps with electrically driven compressors for space heating and cooling'' and... rated according to European Standard EN 14511, ``Air conditioners, liquid chilling packages and heat...

  2. Endow My Air Conditioner!

    ERIC Educational Resources Information Center

    Simmons, Charles E. P.

    1982-01-01

    Administrators need to plan and set priorities in various energy/maintenance areas, and trustees and legislators, faculty and students have to be educated regarding maintenance and conservation. Cost of energy consumption by area and department must be worked out. (MLW)

  3. Experimental investigation of sound absorption properties of perforated date palm fibers panel

    NASA Astrophysics Data System (ADS)

    Elwaleed, A. K.; Nikabdullah, N.; Nor, M. J. M.; Tahir, M. F. M.; Zulkifli, R.

    2013-06-01

    This paper presents the sound absorption properties of a natural waste of date palm fiber perforated panel. A single layer of the date palm fibers was tested in this study for its sound absorption properties. The experimental measurements were carried out using impedance tube at the acoustic lab, Faculty of Engineering, Universiti Kebangsaan Malaysia. The experiment was conducted for the panel without air gap, with air gap and with perforated plate facing. Three air gap thicknesses of 10 mm, 20 mm and 30 mm were used between the date palm fiber sample and the rigid backing of the impedance tube. The results showed that when facing the palm date fiber sample with perforated plate the sound absorption coefficient improved at the higher and lower frequency ranges. This increase in sound absorption coincided with reduction in medium frequency absorption. However, this could be improved by using different densities or perforated plate with the date palm fiber panel.

  4. Air Conditioning in Nearly 100 Million U.S. Homes

    EIA Publications

    2011-01-01

    Except in the temperate climate regions along the West Coast, air conditioners (AC) are now standard equipment in most U.S. homes. As recently as 1993, only 68% of all occupied housing units had AC. The latest results from the 2009 Residential Energy Consumption Survey (RECS) show that 87% of U.S. households are now equipped with AC. This growth occurred among all housing types and in every Census region. Wider use has coincided with much improved energy efficiency standards for AC equipment, a population shift to hotter and more humid regions, and a housing boom during which average housing sizes increased.

  5. Residential Central Air Conditioning and Heat Pump Installation – Workshop Outcomes

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Goetzler, William; Zogg, Robert; Young, Jim

    DOE's Building Technologies Office works with researchers and industry partners to develop and deploy technologies that can substantially reduce energy consumption in residential and commercial buildings. This report aims to advance BTO’s energy savings, emissions reduction, and other program goals by identifying research and development (R&D), demonstration and deployment, and other non-regulatory initiatives for improving the design and installation of residential central air conditioners (CAC) and central heat pumps (CHP). Improving the adoption of CAC/CHP design and installation best practices has significant potential to reduce equipment costs, improve indoor air quality and comfort, improve system performance, and most importantly, reducemore » household energy consumption and costs for heating and cooling by addressing a variety of common installation issues.« less

  6. 75 FR 81287 - Buy American Exceptions Under the American Recovery and Reinvestment Act of 2009

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-12-27

    ... Housing Authority for the purchase and installation of through-the-wall air conditioners, floor-mounted... exception was granted by HUD on the basis that the relevant manufactured goods (through-the-wall air conditioners, floor-mounted water closets, and low voltage electrical components) are not produced in the U.S...

  7. 75 FR 37593 - Energy Conservation Program for Consumer Products: Test Procedures for Clothes Dryers and Room...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-06-29

    ... consumption in clothes dryers and room air conditioners. In addition, DOE is proposing to adopt definitions of... Modes and Off Mode a. Clothes Dryers b. Room Air Conditioners 5. Measures of Energy Consumption a... Gas Dryer Continuously Burning Pilot Light Gas Energy Consumption 9. Clarification of the Gas Supply...

  8. Performance and economics of the ACES and alternative residential heating and air conditioning systems in 115 US cities

    NASA Astrophysics Data System (ADS)

    Abbatiello, L. A.; Nephew, E. A.; Ballou, M. L.

    1981-03-01

    The efficiency and life cycle costs of the brine chiller minimal annual cycle energy system (ACES) for residential space heating, air conditioning, and water heating requirements are compared with three conventional systems. The conventional systems evaluated are a high performance air-to-air heat pump with an electric resistance water heater, an electric furnace with a central air conditioner and an electric resistance water heater, and a high performance air-to-air heat pump with a superheater unit for hot water production. Monthly energy requirements for a reference single family house are calculated, and the initial cost and annual energy consumption of the systems, providing identical energy services, are computed and compared. The ACES consumes one third to one half ot the electrical energy required by the conventional systems and delivers the same annual loads at comparable costs.

  9. Wavelength and energy dependent absorption of unconventional fuel mixtures

    NASA Astrophysics Data System (ADS)

    Khan, N.; Saleem, Z.; Mirza, A. A.

    2005-11-01

    Economic considerations of laser induced ignition over the normal electrical ignition of direct injected Compressed Natural Gas (CNG) engines has motivated automobile industry to go for extensive research on basic characteristics of leaner unconventional fuel mixtures to evaluate practical possibility of switching over to the emerging technologies. This paper briefly reviews the ongoing research activities on minimum ignition energy and power requirements of natural gas fuels and reports results of present laser air/CNG mixture absorption coefficient study. This study was arranged to determine the thermo-optical characteristics of high air/fuel ratio mixtures using laser techniques. We measured the absorption coefficient using four lasers of multiple wavelengths over a wide range of temperatures and pressures. The absorption coefficient of mixture was found to vary significantly over change of mixture temperature and probe laser wavelengths. The absorption coefficients of air/CNG mixtures were measured using 20 watts CW/pulsed CO2 laser at 10.6μm, Pulsed Nd:Yag laser at 1.06μm, 532 nm (2nd harmonic) and 4 mW CW HeNe laser at 645 nm and 580 nm for temperatures varying from 290 to 1000K using optical transmission loss technique.

  10. Computer package for the design and optimization of absorption air conditioning system operated by solar energy

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sofrata, H.; Khoshaim, B.; Megahed, M.

    1980-12-01

    In this paper a computer package for the design and optimization of the simple Li-Br absorption air conditioning system, operated by solar energy, is developed in order to study its performance. This was necessary, as a first step, before carrying out any computations regarding the dual system (1-3). The computer package has the facilities of examining any parameter which may control the system; namely generator, evaporator, condenser, absorber temperatures and pumping factor. The output may be tabulated and also fed to the graph plotter. The flow chart of the programme is explained in an easy way and a typical examplemore » is included.« less

  11. Direct determination of total sulfur in wine using a continuum-source atomic-absorption spectrometer and an air-acetylene flame.

    PubMed

    Huang, Mao Dong; Becker-Ross, Helmut; Florek, Stefan; Heitmann, Uwe; Okruss, Michael

    2005-08-01

    Determination of sulfur in wine is an important analytical task, particularly with regard to food safety legislation, wine trade, and oenology. Hitherto existing methods for sulfur determination all have specific drawbacks, for example high cost and time consumption, poor precision or selectivity, or matrix effects. In this paper a new method, with low running costs, is introduced for direct, reliable, rapid, and accurate determination of the total sulfur content of wine samples. The method is based on measurement of the molecular absorption of carbon monosulfide (CS) in an ordinary air-acetylene flame by using a high-resolution continuum-source atomic-absorption spectrometer including a novel high-intensity short-arc xenon lamp. First results for total sulfur concentrations in different wine samples were compared with data from comparative ICP-MS measurements. Very good agreement within a few percent was obtained.

  12. Optimal coupling and feasibility of a solar-powered year-round ejector air conditioner

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sokolov, M.; Hershgal, D.

    1993-06-01

    An ejector refrigeration system that uses a conventional refrigerant (R-114) is introduced as a possible mechanism for providing solar-based air-conditioning. Optimal coupling conditions between the collectors' energy output and energy requirements of the cooling system, are investigated. Operation at such optimal conditions assures maximized overall efficiency. Procedures leading to the evaluation of the performance of a real system are disclosed. Design curves for such a system with R-114 as refrigerant are provided. A multi-ejectors arrangement that provides an efficient adjustment for variations of ambient conditions, is described. Year-round air-conditioning is facilitated by rerouting the refrigerant flow through a heating modemore » of the system. Calculations are carried out for illustrative configurations in which relatively low condensing temperature (water reservoirs, cooling towers, or moderate climate) can be maintained.« less

  13. Absorption of water and lubricating oils into porous nylon

    NASA Technical Reports Server (NTRS)

    Bertrand, P. A.

    1995-01-01

    Oil and water absorption from air into sintered porous nylon can be described by infiltration into the pores of the material. This process can be modeled by a diffusion-like mechanism. For water absorption, we find a formal diffusion coefficient of 1.5 x 10(exp -4)sq cm/min when the nylon is initially dry. The diffusion coefficient is 4 x 10(exp -6)sq cm/min when the nylon is oil-impregnated prior to air exposure. In a 52% RH atmosphere, dry nylon absorbs 3% w/w water, and oil-impregnated nylon absorbs 0.6% w/w water. For oil absorption there are three steps: (1) surface absorption and infiltration into (2) larger and (3) smaller pores. Surface absorption is too fast to be measured in these experiments. The diffusion coefficient for the second step is 6 x 10(exp -4)sq cm/min for SRG-60 oil into dry nylon and 4 x 10(exp -4)sq cm/min for air-equilibrated nylon. The diffusion coefficient for the third step is about 1 x 10(exp -6)sq cm/min for both cases. The total amount of oil absorbed is 31% w/w. The interaction between water and nylon is not as strong as that between water and cotton-phenolic: oil can replace water, and only a small amount of water can enter previously oil-impregnated nylon.

  14. The development of a solar-powered residential heating and cooling system

    NASA Technical Reports Server (NTRS)

    1974-01-01

    Efforts to demonstrate the engineering feasibility of utilizing solar power for residential heating and cooling are described. These efforts were concentrated on the analysis, design, and test of a full-scale demonstration system which is currently under construction at the National Aeronautics and Space Administration, Marshall Space Flight Center, Huntsville, Alabama. The basic solar heating and cooling system under development utilizes a flat plate solar energy collector, a large water tank for thermal energy storage, heat exchangers for space heating and water heating, and an absorption cycle air conditioner for space cooling.

  15. Using of laser spectroscopy and chemometrics methods for identification of patients with lung cancer, patients with COPD and healthy people from absorption spectra of exhaled air

    NASA Astrophysics Data System (ADS)

    Bukreeva, Ekaterina B.; Bulanova, Anna A.; Kistenev, Yury V.; Kuzmin, Dmitry A.; Nikiforova, Olga Yu.; Ponomarev, Yurii N.; Tuzikov, Sergei A.; Yumov, Evgeny L.

    2014-11-01

    The results of application of the joint use of laser photoacoustic spectroscopy and chemometrics methods in gas analysis of exhaled air of patients with chronic respiratory diseases (chronic obstructive pulmonary disease and lung cancer) are presented. The absorption spectra of exhaled breath of representatives of the target groups and healthy volunteers were measured; the selection by chemometrics methods of the most informative absorption coefficients in scan spectra in terms of the separation investigated nosology was implemented.

  16. Analysis of an Air Conditioning Coolant Solution for Metal Contamination Using Atomic Absorption Spectroscopy: An Undergraduate Instrumental Analysis Exercise Simulating an Industrial Assignment

    ERIC Educational Resources Information Center

    Baird, Michael J.

    2004-01-01

    A real-life analytical assignment is presented to students, who had to examine an air conditioning coolant solution for metal contamination using an atomic absorption spectroscopy (AAS). This hands-on access to a real problem exposed the undergraduate students to the mechanism of AAS, and promoted participation in a simulated industrial activity.

  17. A study of the H2O absorption line shifts in the visible spectrum region due to air pressure

    NASA Technical Reports Server (NTRS)

    Grossmann, B. E.; Browell, E. V.; Bykov, A. D.; Kapitanov, V. A.; Korotchenko, E. A.

    1990-01-01

    Results of measured and calculated shift coefficients are presented for 170 absorption lines of H2O in five vibrational-rotational bands. The measurements have been carried out using highly sensitive laser spectrometers with a resolution of at least 0.01/cm; the calculations are based on the Anderson-Tsao-Curnutte-Frost method. Good agreement is obtained between the theoretical and experimental values of the shift coefficients of H2O lines due to N2, O2, and air pressure.

  18. 77 FR 2355 - Energy Conservation Program for Certain Industrial Equipment: Energy Conservation Standards and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-01-17

    ... any person wishing to bring a laptop computer into the Forrestal Building will be required to obtain a...; VRF water-source heat pumps at or greater than 135,000 Btu/h; and computer room air conditioners. DOE...-created classes of variable refrigerant flow air conditioners and heat pumps, ASHRAE 127 for computer room...

  19. The application of the analog signal to discrete time interval converter to the signal conditioner power supplies

    NASA Technical Reports Server (NTRS)

    Schoenfeld, A. D.; Yu, Y.

    1973-01-01

    The Analog Signal to Discrete Time Interval Converter microminiaturized module was utilized to control the signal conditioner power supplies. The multi-loop control provides outstanding static and dynamic performance characteristics, exceeding those generally associated with single-loop regulators. Eight converter boards, each containing three independent dc to dc converter, were built, tested, and delivered.

  20. Differential effects of air conditioning type on residential endotoxin levels in a semi-arid climate.

    PubMed

    Johnston, J D; Kruman, B A; Nelson, M C; Merrill, R M; Graul, R J; Hoybjerg, T G; Tuttle, S C; Myers, S J; Cook, R B; Weber, K S

    2017-09-01

    Residential endotoxin exposure is associated with protective and pathogenic health outcomes. Evaporative coolers, an energy-efficient type of air conditioner used in dry climates, are a potential source of indoor endotoxins; however, this association is largely unstudied. We collected settled dust biannually from four locations in homes with evaporative coolers (n=18) and central air conditioners (n=22) in Utah County, Utah (USA), during winter (Jan-Apr) and summer (Aug-Sept), 2014. Dust samples (n=281) were analyzed by the Limulus amebocyte lysate test. Housing factors were measured by survey, and indoor temperature and relative humidity measures were collected during both seasons. Endotoxin concentrations (EU/mg) were significantly higher in homes with evaporative coolers from mattress and bedroom floor samples during both seasons. Endotoxin surface loads (EU/m 2 ) were significantly higher in homes with evaporative coolers from mattress and bedroom floor samples during both seasons and in upholstered furniture during winter. For the nine significant season-by-location comparisons, EU/mg and EU/m 2 were approximately three to six times greater in homes using evaporative coolers. A plausible explanation for these findings is that evaporative coolers serve as a reservoir and distribution system for Gram-negative bacteria or their cell wall components in homes. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  1. Remote air pollution measurement

    NASA Technical Reports Server (NTRS)

    Byer, R. L.

    1975-01-01

    This paper presents a discussion and comparison of the Raman method, the resonance and fluorescence backscatter method, long path absorption methods and the differential absorption method for remote air pollution measurement. A comparison of the above remote detection methods shows that the absorption methods offer the most sensitivity at the least required transmitted energy. Topographical absorption provides the advantage of a single ended measurement, and differential absorption offers the additional advantage of a fully depth resolved absorption measurement. Recent experimental results confirming the range and sensitivity of the methods are presented.

  2. Practical demonstration of heat pumps for utilization of animal-generated heat

    NASA Astrophysics Data System (ADS)

    Amberg, H. U.

    1980-09-01

    Airconditioning of pigpens to eliminate effects of temperature extremes is reported. A stall air conditioner was installed as heat pump in a pigpen for final fattening. The heat, recovered from the exhaust air, is supplied to the outside air so that heated fresh air is blown into the stall. The test was accomplished on a farm with intensive pig breeding with 120 preliminary fattening places and 240 final fattening places. The stall air conditioner offers the possibility to attenuate the extreme temperature variations during the year.

  3. Multi-load Groups Coordinated Load Control Strategy Considering Power Network Constraints

    NASA Astrophysics Data System (ADS)

    Liu, Meng; Zhao, Binchao; Wang, Jun; Zhang, Guohui; Wang, Xin

    2017-05-01

    Loads with energy storage property can actively participate in power balance for power systems, this paper takes air conditioner as a controllable load example, proposing a multi-load groups coordinated load control strategy considering power network constraints. Firstly, two load control modes considering recovery of load diversity are designed, blocking power oscillation of aggregated air conditioners. As the same time, air conditioner temperature setpoint recovery control strategy is presented to avoid power recovery peak. Considering inherent characteristics of two load control modes, an coordinated load control mode is designed by combining the both. Basing on this, a multi-load groups coordinated load control strategy is proposed. During the implementing of load control, power network constraints should be satisfied. An indice which can reflect the security of power system operating is defined. By minimizing its value through optimization, the change of air conditioning loads’ aggregated power on each load bus can be calculated. Simulations are conducted on an air conditioners group and New England 10-generator 39-bus system, verifying the effectiveness of the proposed multi-load groups coordinated load control strategy considering power network constraints.

  4. Development of indoor environmental index: Air quality index and thermal comfort index

    NASA Astrophysics Data System (ADS)

    Saad, S. M.; Shakaff, A. Y. M.; Saad, A. R. M.; Yusof, A. M.; Andrew, A. M.; Zakaria, A.; Adom, A. H.

    2017-03-01

    In this paper, index for indoor air quality (also known as IAQI) and thermal comfort index (TCI) have been developed. The IAQI was actually modified from previous outdoor air quality index (AQI) designed by the United States Environmental Protection Agency (US EPA). In order to measure the index, a real-time monitoring system to monitor indoor air quality level was developed. The proposed system consists of three parts: sensor module cloud, base station and service-oriented client. The sensor module cloud (SMC) contains collections of sensor modules that measures the air quality data and transmit the captured data to base station through wireless. Each sensor modules includes an integrated sensor array that can measure indoor air parameters like Carbon Dioxide, Carbon Monoxide, Ozone, Nitrogen Dioxide, Oxygen, Volatile Organic Compound and Particulate Matter. Temperature and humidity were also being measured in order to determine comfort condition in indoor environment. The result from several experiments show that the system is able to measure the air quality presented in IAQI and TCI in many indoor environment settings like air-conditioner, chemical present and cigarette smoke that may impact the air quality. It also shows that the air quality are changing dramatically, thus real-time monitoring system is essential.

  5. Efficacy of Neem Extract and Three Antimicrobial Agents Incorporated into Tissue Conditioner in Inhibiting the Growth of C. Albicans and S. Mutans

    PubMed Central

    Barua, Dikshita Ray; Varghese, Rana Kalappattil

    2017-01-01

    Introduction Denture stomatitis is an inflammatory condition which compromises the mucosal surface beneath dentures. The aetiology of denture stomatitis is usually multifactorial which varies from trauma from ill fitting denture to poor immune system. There are evidences that denture stomatitis is an outcome of multispecies biofilms that include Candida albicans and Streptococcus mutans. Tissue conditioners are found to be more susceptible to colonisation by micro-organisms. Aim The purpose of this study was to compare the efficacy of neem leaf extract and three other antimicrobial agents incorporated in a tissue conditioner against both Candida albicans and Streptococcus mutans. Materials and Methods Standard strain of Candida albicans and Streptococcus mutans were inoculated into Sabouraud Dextrose broth and Mitis-Salivarius-Bacitracin broth respectively incubated at 37°C. Tissue conditioner (Viscogel) mixed with two different concentrations of ketoconazole, nystatin and chlorhexidine diacetate (5%, 10% w/w) and neem leaf extract (7.5% w/w and 15% w/w) and control group (plain tissue conditioner) were placed into punch hole (6 mm diameter) agar plate inoculated with Candida albicans and Streptococcus mutans. A total of 216 samples were prepared for both Candida albicans and Streptococcus mutans. Mean Inhibition Diameter (MID) across each punch holes were measured in millimetres at 24 hours and seven days and data were statistically analysed using Kruskal Wallis test followed by Mann-Whitney U test. Results Both ketoconazole and nystatin (10% w/w) showed maximum inhibition of 32 mm and mean of 31.75 followed by 15% w/w neem leaf extract with an inhibition of 21 mm and mean of 20.67 after 24 hours against Candida albicans whereas chlorhexidine diacetate (10% w/w) showed mean of 25.67 followed by chlorhexidine diacetate (5% w/w) and neem extract (15% w/w) which showed mean of 24.17 and 23.67 respectively against Streptococcus mutans. Conclusion Neem leaf extract

  6. Impacts of soil conditioners and water table management on phosphorus loss in tile drainage from a clay loam soil.

    PubMed

    Zhang, T Q; Tan, C S; Zheng, Z M; Welacky, T W; Reynolds, W D

    2015-03-01

    Adoption of waste-derived soil conditioners and refined water management can improve soil physical quality and crop productivity of fine-textured soils. However, the impacts of these practices on water quality must be assessed to ensure environmental sustainability. We conducted a study to determine phosphorus (P) loss in tile drainage as affected by two types of soil conditioners (yard waste compost and swine manure compost) and water table management (free drainage and controlled drainage with subirrigation) in a clay loam soil under corn-soybean rotation in a 4-yr period from 1999 to 2003. Tile drainage flows were monitored and sampled on a year-round continuous basis using on-site auto-sampling systems. Water samples were analyzed for dissolved reactive P (DRP), particulate P (PP), and total P (TP). Substantially greater concentrations and losses of DRP, PP, and TP occurred with swine manure compost than with control and yard waste compost regardless of water table management. Compared with free drainage, controlled drainage with subirrigation was an effective way to reduce annual and cumulative losses of DRP, PP, and TP in tile drainage through reductions in flow volume and P concentration with control and yard waste compost but not with swine manure compost. Both DRP and TP concentrations in tile drainage were well above the water quality guideline for P, affirming that subsurface loss of P from fine-textured soils can be one critical source for freshwater eutrophication. Swine manure compost applied as a soil conditioner must be optimized by taking water quality impacts into consideration. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  7. Effects of excess levels of a polymer as a soil conditioner on yields and mineral nutrition of plants. [Triticum aestivum; Lycopersicon esculentum

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wallace, A.; Wallace, G.A.; Abouzamzam, A.M.

    Wheat (Triticum aestivum L. cv. INIA66R) and tomato (Lycopersicon esculentum Mill. cv. Tropic) were grown in containers with a Xerorthents soil and with levels of an anionic soil conditioner far in excess of that needed for adequate stabilization of soil. The 1% rate increased the vegetative growth of plants over controls, and the 5% rate gave yields more nearly like controls. The anionic polymer decreased accumulation of the anions P and Si in all plants and decreased Mn and B in wheat only. The highest level of polymer also depressed accumulation of some of the macroelement cations. Both levels ofmore » polymer created 100% water-stable aggregates compared with only 38% in the control. The potential for toxicity of polyacrylamide soil conditioners is discussed.« less

  8. Building America Case Study: Residential Mechanical Precooling, Roseville, California

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    A. German and M. Hoeschele

    2017-05-01

    Precooling is an operational strategy with potentially no up-front cost that cools occupied spaces earlier in the day to minimize or avoid afternoon air conditioner operation. In its simplest form, precooling can be implemented by scheduling air conditioner operation to reduce thermostat setpoints between 2 degrees and 6 degrees F below typical comfort settings in advance of the on-peak time period.

  9. Building America Case Study: Residential Mechanical Precooling, Roseville, California

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    2017-05-08

    Precooling is an operational strategy with potentially no up-front cost that cools occupied spaces earlier in the day to minimize or avoid afternoon air conditioner operation. In its simplest form, precooling can be implemented by scheduling air conditioner operation to reduce thermostat setpoints between 2 degrees and 6 degrees F below typical comfort settings in advance of the on-peak time period.

  10. Wave energy absorption by a floating air bag

    NASA Astrophysics Data System (ADS)

    Kurniawan, A.; Chaplin, J. R.; Greaves, D. M.; Hann, M.

    2017-02-01

    A floating air bag, ballasted in water, expands and contracts as it heaves under wave action. Connecting the bag to a secondary volume via a turbine transforms the bag into a device capable of generating useful energy from the waves. Small-scale measurements of the device reveal some interesting properties, which are successfully predicted numerically. Owing to its compressibility, the device can have a heave resonance period longer than that of a rigid device of the same shape and size, without any phase control. Furthermore, varying the amount of air in the bag is found to change its shape and hence its dynamic response, while varying the turbine damping or the air volume ratio changes the dynamic response without changing the shape.

  11. Initiation of air ionization by ultrashort laser pulses: evidence for a role of metastable-state air molecules

    NASA Astrophysics Data System (ADS)

    Bulgakov, A. V.; Mirza, I.; Bulgakova, N. M.; Zhukov, V. P.; Machulka, R.; Haderka, O.; Campbell, E. E. B.; Mocek, T.

    2018-06-01

    Transmission measurements for femtosecond laser pulses focused in air with spectral analysis of emission from the focal region have been carried out for various pulse energies and air pressures. The air breakdown threshold and pulse attenuation due to plasma absorption are evaluated and compared with calculations based on the multiphoton ionization model. The plasma absorption is found to depend on the pulse repetition rate and is considerably stronger at 1 kHz than at 1–10 Hz. This suggests that accumulation of metastable states of air molecules plays an important role in initiation of air breakdown, enhancing the ionization efficiency at high repetition rates. Possible channels of metastable-state-assisted air ionization and the role of the observed accumulation effect in laser material processing are discussed.

  12. Evaluation of initial collector field performance at the Langley Solar Building Test Facility

    NASA Technical Reports Server (NTRS)

    Boyle, R. J.; Jensen, R. N.; Knoll, R. H.

    1977-01-01

    The thermal performance of the solar collector field for the NASA Langley Solar Building Test Facility is given for October 1976 through January 1977. A 1,180 square meter solar collector field with seven collector designs helped to provide hot water for the building heating system and absorption air conditioner. The collectors were arranged in 12 rows with nominally 51 collectors per row. Heat transfer rates for each row were calculated and recorded along with sensor, insolation, and weather data every five minutes using a minicomputer. The agreement between the experimental and predicted collector efficiencies was generally within five percentage points.

  13. Evaluation of initial collector field performance at the Langley Solar Building Test Facility

    NASA Technical Reports Server (NTRS)

    Boyle, R. J.; Knoll, R. H.; Jensen, R. N.

    1977-01-01

    The thermal performance of the solar collector field for the NASA Langley Solar Building Test Facility is given for October 1976 through January 1977. An 1180 square meter solar collector field with seven collector designs helped to provide hot water for the building heating system and absorption air conditioner. The collectors were arranged in 12 rows with nominally 51 collectors per row. Heat transfer rates for each row are calculated and recorded along with sensor, insolation, and weather data every 5 minutes using a mini-computer. The agreement between the experimental and predicted collector efficiencies was generally within five percentage points.

  14. Experimental Evaluation of Fuzzy Logic Control of a Flexible Arm Manipulator

    DTIC Science & Technology

    1993-12-09

    temperature into a fuzzy context), and humidity is musty, Then air conditioner power is high. The database and knowledge base combine to form the...this case, the output, perhaps air conditioner power, would be medium to a degree of 50%. However, as shown in Table 3.2, Oare are more possible...OF WASHINGTON AFIT/CI/CIA-93-167 9. SPONSORING/MONITORING AGENCY NAME(S) AND ADDRESS(ES) 10. SPONSORING/MONITORING DEPARTMENI OF THE AIR FORCE AGENCY

  15. Dehumidifying Heat Pipe

    NASA Technical Reports Server (NTRS)

    Khattar, Mukesh K.

    1993-01-01

    U-shaped heat pipe partly dehumidifies air leaving air conditioner. Fits readily in air-handling unit of conditioner. Evaporator and condenser sections of heat pipe consist of finned tubes in comb pattern. Each tube sealed at one end and joined to manifold at other. Sections connected by single pipe carrying vapor to condenser manifold and liquid to evaporator manifold. Simple on/off or proportional valve used to control flow of working fluid. Valve actuated by temperature/humidity sensor.

  16. DOE Office of Scientific and Technical Information (OSTI.GOV)

    Chang, M.; Lee, S.C.

    The indoor and outdoor levels of VOCs and PM{sub 2.5} were measured at two classrooms of two schools; one is naturally ventilated, while the other had two window type air-conditioners and four exhaust fans. The ventilation rates at the two classrooms were 0.937 ACH (Classroom A) and 0.217 ACH (Classroom B). Both classrooms had ventilation requirements below the ASHRAE Standard 62-1989 assuming that the outdoor contaminant levels were within the ASHRAE requirements. The abundance and concentration of volatile organic species found indoors and outdoors of Classroom B were higher than Classroom A since Classroom B is located in a heavilymore » trafficked area. The classroom without air-conditioner (A) had higher I/O ratios than Classroom B due to the higher ventilation rates. The air-conditioner, though not providing enough fresh air to the classroom, might act as a barrier for outdoor pollutants. The reduction of PM2.5 levels Classroom A was 30% and at Classroom B was 67%. The air-conditioning system in Classroom B could be removing some of the fine particulate matter from the outdoor supply air before entering the classroom. The use of air-conditioners can keep outdoor pollutants from entering the classroom, but could increase the level of indoor produced pollutant. From this study, air-conditioning systems in classroom somehow prevent pollutants from entering, and besides used to lowering environmental noise should be encouraged at schools located in heavily polluted environments.« less

  17. The development of a solar residential heating and cooling system

    NASA Technical Reports Server (NTRS)

    1975-01-01

    The MSFC solar heating and cooling facility was assembled to demonstrate the engineering feasibility of utilizing solar energy for heating and cooling buildings, to provide an engineering evaluation of the total system and the key subsystems, and to investigate areas of possible improvement in design and efficiency. The basic solar heating and cooling system utilizes a flat plate solar energy collector, a large water tank for thermal energy storage, heat exchangers for space heating, and an absorption cycle air conditioner for space cooling. A complete description of all systems is given. Development activities for this test system included assembly, checkout, operation, modification, and data analysis, all of which are discussed. Selected data analyses for the first 15 weeks of testing are included, findings associated with energy storage and the energy storage system are outlined, and conclusions resulting from test findings are provided. An evaluation of the data for summer operation indicates that the current system is capable of supplying an average of 50 percent of the thermal energy required to drive the air conditioner. Preliminary evaluation of data collected for operation in the heating mode during the winter indicates that nearly 100 percent of the thermal energy required for heating can be supplied by the system.

  18. A Line Impedance Conditioner for Saturation Mitigation of Zigzag Transformer in Hybrid AC/DC Transmission System Considering Line Unbalances

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Liu, Bo; Shi, Xiaojie M.; Li, Yalong

    Hybrid ac/dc transmission extends the power transfer capacity of existing long ac lines closer to their thermal limit, by superposing the dc current onto three-phase ac lines through a zigzag transformer. However, this transformer could suffer saturation under unbalanced line impedance conditions. This paper introduces the concept of hybrid line impedance conditioner (HLIC) as a cost-effective approach to compensate for the line unbalance and therefore avoid saturation. The topology and operation principle are presented. The two-level control strategy is described, which enables autonomous adaptive regulation without the need of system-level control. Design and implementation are also analyzed, including dc-link capacitancemore » as one of the key line conditioner components, HLIC installation, and protection under fault conditions. The cost study on this HLIC-based hybrid system is also performed to reveal the benefits of the solution. In conclusion, simulation results and experimental results based on a down-scaled prototype are provided to verify the feasibility of the proposed approach.« less

  19. A Line Impedance Conditioner for Saturation Mitigation of Zigzag Transformer in Hybrid AC/DC Transmission System Considering Line Unbalances

    DOE PAGES

    Liu, Bo; Shi, Xiaojie M.; Li, Yalong; ...

    2016-09-13

    Hybrid ac/dc transmission extends the power transfer capacity of existing long ac lines closer to their thermal limit, by superposing the dc current onto three-phase ac lines through a zigzag transformer. However, this transformer could suffer saturation under unbalanced line impedance conditions. This paper introduces the concept of hybrid line impedance conditioner (HLIC) as a cost-effective approach to compensate for the line unbalance and therefore avoid saturation. The topology and operation principle are presented. The two-level control strategy is described, which enables autonomous adaptive regulation without the need of system-level control. Design and implementation are also analyzed, including dc-link capacitancemore » as one of the key line conditioner components, HLIC installation, and protection under fault conditions. The cost study on this HLIC-based hybrid system is also performed to reveal the benefits of the solution. In conclusion, simulation results and experimental results based on a down-scaled prototype are provided to verify the feasibility of the proposed approach.« less

  20. Measurement of Absorption Coefficient of Paraformaldehyde and Metaldehyde with Terahertz Spectroscopy

    NASA Astrophysics Data System (ADS)

    Zhang, J.; Xia, T.; Chen, Q.; Sun, Q.; Deng, Y.; Wang, C.

    2018-03-01

    The characteristic absorption spectra of paraformaldehyde and metaldehyde in the terahertz frequency region are obtained by terahertz time-domain spectroscopy (THz-TDS). In order to reduce the absorption of terahertz (THz) wave by water vapor in the air and the background noise, the measurement system was filled with dry air and the measurements were conducted at the temperature of 24°C. Meanwhile, the humidity was controlled within 10% RH. The THz frequency domain spectra of samples and their references from 0 to 2.5 THz were analyzed via Fourier transform. The refractive index and absorption coefficients of the two aldehydes were calculated by the model formulas. From 0.1 to 2.5 THz, there appear two weak absorption peaks at 1.20 and 1.66 THz in the absorption spectra of paraformaldehyde. Only one distinct absorption peak emerges at 1.83 THz for metaldehyde. There are significant differences between the terahertz absorption coefficients of paraformaldehyde and metaldehyde, which can be used as "fingerprints" to identify these substances. Furthermore, the relationship between the average absorption coefficients and mass concentrations was investigated and the average absorption coefficient-mass concentration diagrams of paraformaldehyde and metaldehyde were shown. For paraformaldehyde, there is a linear relationship between the average absorption coefficient and the natural logarithm of mass concentration. For metaldehyde, there exists a simpler linear relationship between the average absorption coefficient and the mass concentration. Because of the characteristics of THz absorption of paraformaldehyde and metaldehyde, the THz-TDS can be applied to the qualitative and quantitative detection of the two aldehydes to reduce the unpredictable hazards due to these substances.

  1. Fundamental absorption edge of NiO nanocrystals

    NASA Astrophysics Data System (ADS)

    Sokolov, V. I.; Druzhinin, A. V.; Kim, G. A.; Gruzdev, N. B.; Yermakov, A. Ye.; Uimin, M. A.; Byzov, I. V.; Shchegoleva, N. N.; Vykhodets, V. B.; Kurennykh, T. E.

    2013-12-01

    NiO nanocrystals with the average size of 5, 10 and 25 nm were synthesized by gas-condensation method. The well-defined increase of the optical density D near the fundamental absorption edge of NiO nanocrystals in the range of 3.5-4.0 eV observed after the annealing in air is caused by the oxygen content growth. It is the direct experimental evidence of the fact that p-d charge transfer transitions form the fundamental absorption edge.

  2. Investigation into the common mode rejection ratio of the physiological signal conditioner circuit

    NASA Technical Reports Server (NTRS)

    Obrien, Edward M.

    1992-01-01

    The common mode rejection ratio (CMRR) of the single operational amplifier (op amp) differential amplifier and of the three operational amplifier differential amplifier was investigated. The three op amp differential amplifier circuit is used in the signal conditioner circuit which amplifies signals such as the electromyograph or electrocardiogram. The investigation confirmed via SPICE modeling what has been observed by others in the recent literature that the CMRR for the circuit can be maximized without precision resistor values or precisely matched op amps. This can be done if one resistor in the final stage can be adjusted either by a potentiometer or by laser trimming in the case of hybrid circuit fabrication.

  3. 30 CFR 7.97 - Application requirements.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... sensors, flame arresters, exhaust conditioner, emergency intake air shutoff device, automatic fuel shutoff...-cooled components, coolant lines, radiator, surge tank, temperature sensors, and orifices; arrows... internal parts, exhaust inlet and outlet, sensors, and the exhaust gas path through the exhaust conditioner...

  4. 30 CFR 7.97 - Application requirements.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... sensors, flame arresters, exhaust conditioner, emergency intake air shutoff device, automatic fuel shutoff...-cooled components, coolant lines, radiator, surge tank, temperature sensors, and orifices; arrows... internal parts, exhaust inlet and outlet, sensors, and the exhaust gas path through the exhaust conditioner...

  5. 30 CFR 7.97 - Application requirements.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... sensors, flame arresters, exhaust conditioner, emergency intake air shutoff device, automatic fuel shutoff...-cooled components, coolant lines, radiator, surge tank, temperature sensors, and orifices; arrows... internal parts, exhaust inlet and outlet, sensors, and the exhaust gas path through the exhaust conditioner...

  6. An experimental investigation of compressor stall using an on-line distortion indicator and signal conditioner

    NASA Technical Reports Server (NTRS)

    Costakis, W. G.; Wenzel, L. M.

    1975-01-01

    The relation of the steady-state and dynamic distortions and the stall margin of a J85-13 turbojet engine was investigated. A distortion indicator capable of computing two distortion indices was used. A special purpose signal conditioner was also used as an interface between transducer signals and distortion indicator. A good correlation of steady-state distortion and stall margin was established. The prediction of stall by using the indices as instantaneous distortion indicators was not successful. A sensitivity factor that related the loss of stall margin to the turbulence level was found.

  7. Design and Analysis of a Two-Stage Adsorption Air Chiller

    NASA Astrophysics Data System (ADS)

    Benrajesh, P.; Rajan, A. John

    2017-05-01

    The objective of this article is to design and build a bio-friendly air-conditioner, by using adsorption method in the presence of 15% of calcium carbide in water. Aluminum sheet metals are used to form three identical tunnels, to pass the air for processing. Exhaust heat generated from the dairy sterilizing unit process is reutilized, for cooling the environment through this equipment. This equipment is designed, and the analysis is carried out to quantify the COP, SCP, and cooling power. Heat exchangers are designed; its Performance Parameters are quantified and correlated with the conventional designs. It is observed that the new adsorption chiller can produce the coefficient of performance of chiller as 1.068; the Specific cooling power of 10.66 (W/Kg); and the Cooling power of 4.2 KW. This equipment needs 0 to 15 minutes to reach the desired cool breeze (24°c) from the existing room temperature (29°c).

  8. 30 CFR 7.97 - Application requirements.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... internal parts, exhaust inlet and outlet, sensors, and the exhaust gas path through the exhaust conditioner... temperature sensor setting and exhaust gas temperature sensor setting used to meet the performance... sensors, flame arresters, exhaust conditioner, emergency intake air shutoff device, automatic fuel shutoff...

  9. 30 CFR 7.97 - Application requirements.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... internal parts, exhaust inlet and outlet, sensors, and the exhaust gas path through the exhaust conditioner... temperature sensor setting and exhaust gas temperature sensor setting used to meet the performance... sensors, flame arresters, exhaust conditioner, emergency intake air shutoff device, automatic fuel shutoff...

  10. 2. VIEW IN ROOM 111, ATOMIC ABSORPTION BERYLLIUM ANALYSIS LABORATORY. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    2. VIEW IN ROOM 111, ATOMIC ABSORPTION BERYLLIUM ANALYSIS LABORATORY. AIR FILTERS AND SWIPES ARE DISSOLVED WITH ACIDS AND THE REMAINING RESIDUES ARE SUSPENDED IN NITRIC ACID SOLUTION. THE SOLUTION IS PROCESSED THROUGH THE ATOMIC ABSORPTION SPECTROPHOTOMETER TO DETECT THE PRESENCE AND LEVELS OF BERYLLIUM. - Rocky Flats Plant, Health Physics Laboratory, On Central Avenue between Third & Fourth Streets, Golden, Jefferson County, CO

  11. 76 FR 76328 - Energy Conservation Program: Enforcement of Regional Standards for Residential Furnaces and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-12-07

    ... contractors in the product supply chain. The Department is considering these approaches or some combination of... Conditioners and Heat Pumps AGENCY: Office of Energy Efficiency and Renewable Energy, Department of Energy... efficiency standards for residential furnaces and residential central air conditioners and heat pumps. DOE...

  12. Potential Evaluation of Solar Heat Assisted Desiccant Hybrid Air Conditioning System

    NASA Astrophysics Data System (ADS)

    Tran, Thien Nha; Hamamoto, Yoshinori; Akisawa, Atsushi; Kashiwagi, Takao

    The solar thermal driven desiccant dehumidification-absorption cooling hybrid system has superior advantage in hot-humid climate regions. The reasonable air processing of desiccant hybrid air conditioning system and the utility of clean and free energy make the system environment friendly and energy efficient. The study investigates the performance of the desiccant dehumidification air conditioning systems with solar thermal assistant. The investigation is performed for three cases which are combinations of solar thermal and absorption cooling systems with different heat supply temperature levels. Two solar thermal systems are used in the study: the flat plate collector (FPC) and the vacuum tube with compound parabolic concentrator (CPC). The single-effect and high energy efficient double-, triple-effect LiBr-water absorption cooling cycles are considered for cooling systems. COP of desiccant hybrid air conditioning systems are determined. The evaluation of these systems is subsequently performed. The single effect absorption cooling cycle combined with the flat plate collector solar system is found to be the most energy efficient air conditioning system.

  13. Method and apparatus for analog signal conditioner for high speed, digital x-ray spectrometer

    DOEpatents

    Warburton, William K.; Hubbard, Bradley

    1999-01-01

    A signal processing system which accepts input from an x-ray detector-preamplifier and produces a signal of reduced dynamic range for subsequent analog-to-digital conversion. The system conditions the input signal to reduce the number of bits required in the analog-to-digital converter by removing that part of the input signal which varies only slowly in time and retaining the amplitude of the pulses which carry information about the x-rays absorbed by the detector. The parameters controlling the signal conditioner's operation can be readily supplied in digital form, allowing it to be integrated into a feedback loop as part of a larger digital x-ray spectroscopy system.

  14. Corrosion inhibitor for aqueous ammonia absorption system

    DOEpatents

    Phillips, Benjamin A.; Whitlow, Eugene P.

    1998-09-22

    A method of inhibiting corrosion and the formation of hydrogen and thus improving absorption in an ammonia/water absorption refrigeration, air conditioning or heat pump system by maintaining the hydroxyl ion concentration of the aqueous ammonia working fluid within a selected range under anaerobic conditions at temperatures up to 425.degree. F. This hydroxyl ion concentration is maintained by introducing to the aqueous ammonia working fluid an inhibitor in an amount effective to produce a hydroxyl ion concentration corresponding to a normality of the inhibitor relative to the water content ranging from about 0.015 N to about 0.2 N at 25.degree. C. Also, working fluids for inhibiting the corrosion of carbon steel and resulting hydrogen formation and improving absorption in an ammonia/water absorption system under anaerobic conditions at up to 425.degree. F. The working fluids may be aqueous solutions of ammonia and a strong base or aqueous solutions of ammonia, a strong base, and a specified buffer.

  15. Corrosion inhibitor for aqueous ammonia absorption system

    DOEpatents

    Phillips, B.A.; Whitlow, E.P.

    1998-09-22

    A method is described for inhibiting corrosion and the formation of hydrogen and thus improving absorption in an ammonia/water absorption refrigeration, air conditioning or heat pump system by maintaining the hydroxyl ion concentration of the aqueous ammonia working fluid within a selected range under anaerobic conditions at temperatures up to 425 F. This hydroxyl ion concentration is maintained by introducing to the aqueous ammonia working fluid an inhibitor in an amount effective to produce a hydroxyl ion concentration corresponding to a normality of the inhibitor relative to the water content ranging from about 0.015 N to about 0.2 N at 25 C. Also, working fluids for inhibiting the corrosion of carbon steel and resulting hydrogen formation and improving absorption in an ammonia/water absorption system under anaerobic conditions at up to 425 F. The working fluids may be aqueous solutions of ammonia and a strong base or aqueous solutions of ammonia, a strong base, and a specified buffer. 5 figs.

  16. Retrieval of methanol absorption parameters at terahertz frequencies using multispectral fitting

    NASA Astrophysics Data System (ADS)

    Slocum, David M.; Xu, Li-Hong; Giles, Robert H.; Goyette, Thomas M.

    2015-12-01

    A high-resolution broadband study of the methanol absorption spectrum was performed at 1.480-1.495 THz. The transmittance was recorded under both self- and air-broadening conditions for multiple pressures at a resolution of 500 kHz. A multispectral fitting analysis was then performed. The transition frequency, absolute intensity, self- and air-broadening coefficients, and self- and air-induced pressure shifts were retrieved for 221 absorption lines using the multispectral fitting routine. Observed in the data were two different series of transitions, both a b-type Q-branch with K = - 7 ← - 6 and an a-type R-branch with J = 31 ← 30 . The retrieved frequency position values were compared with values from spectral databases and trends within the different series were identified. An analysis of the precision of the fitting routine was also performed.

  17. Sewage sludge as conditioner for improving soils affected by sulfur dioxide

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Wong, M.K.

    1979-12-01

    Continuous emission of SO/sub 2/ from the acid manufacturing plant at Ching Lung Tau, New Territorise of Honk Kong, damaged most of the surrounding vegetation, leaving only a few comparatively more resistant species, e.g. Eragrostis sp., Ischaemum aristatum, Smilax glabra, etc. Erosion occurred after heavy rainfall. Fine particles were washed away, leaving the non-fertile subsoil which lack nutrients. The utilization of sludge as a soil conditioner has been regarded as a method of sludge disposal which not only solves some of the pollution problems but receives benefit from the waste product. A considerable amount of literature has been concerned withmore » improving infertile soil including the reclamation of spoiled land, e.g. coal mine spoils, iron-ore tailing. The present investigation attempts to study the effect of applying digested sewage sludge to eroded soil using laboratory soil columns and a green house trial.« less

  18. Refrigeration oils for low GWP refrigerants in various applications

    NASA Astrophysics Data System (ADS)

    Saito, R.; Sundaresan, S. G.

    2017-08-01

    The practical use of the refrigeration systems is considered as a methods to suppress global warming. The replacement of a refrigerant with a new one that has lower global warming potential (GWP) has been underway for several years. For the application fields of refrigerators, domestic air conditioners, automotive air conditioners and hot water dispensers, the investigation has almost finished. It is still underway for the application fields of commercial air conditioners and chillers, refrigeration facilities for cold storage, etc. And now, the refrigeration system is being applied in various ways to decrease global warming above the generation of electric power with organic Rankine cycle, the binary electric generation with ground source heat pump, and so on. In these situations, various refrigerants are developed and several kinds of suitable refrigeration oils are selected. This paper presents the consideration of suitable refrigeration oil for the various low GWP refrigerants.

  19. Depletion of the vibrational ground state of CH4 in absorption spectroscopy at 3.4 μm in N2 and air in the 1-100 Torr range

    NASA Astrophysics Data System (ADS)

    Hausmaninger, Thomas; Zhao, Gang; Ma, Weiguang; Axner, Ove

    2018-01-01

    A model presented in an accompanying work predicts that mid-IR absorption signals from methane in trace concentrations in various buffer gases detected at pressures in the 1-100 Torr range can be reduced and distorted due to depletion of the vibrational ground state if the molecules are exposed to laser powers in the tens of mW range or above. This work provides experimental evidence of such depletion in a resonant cavity under a variety of conditions, e.g. for intracavity laser powers up to 2 W and for buffer gases of N2 or dry air, and verifies the applicability of the model. It was found that the degree of depletion is significantly larger in N2 than dry air, and that it increases with pressure for pressures up to around 10 Torr (attributed to a decreased diffusion rate) but decreases with pressure for pressures above 20 Torr (caused by an increased collisional vibrational decay rate). The maximum degree of depletion (∼80%) was obtained for methane in N2 at around 15 Torr. This implies that absorption spectrometry of methane can experience significant non-linear dependencies on laser power, pressure, as well as buffer gas composition. It is shown that depletion takes place also in 13CH4, which verifies the applicability of the model also for this isotopologue, and that NICE-OHMS signals detected in absorption phase are less affected by depletion than in dispersion. It was concluded that the absorption mode of detection can provide concentration assessments that are virtually free of influence of depletion for intracavity powers below 0.8 W.

  20. High temperature measurement of water vapor absorption

    NASA Technical Reports Server (NTRS)

    Keefer, Dennis; Lewis, J. W. L.; Eskridge, Richard

    1985-01-01

    An investigation was undertaken to measure the absorption coefficient, at a wavelength of 10.6 microns, for mixtures of water vapor and a diluent gas at high temperature and pressure. The experimental concept was to create the desired conditions of temperature and pressure in a laser absorption wave, similar to that which would be created in a laser propulsion system. A simplified numerical model was developed to predict the characteristics of the absorption wave and to estimate the laser intensity threshold for initiation. A non-intrusive method for temperature measurement utilizing optical laser-beam deflection (OLD) and optical spark breakdown produced by an excimer laser, was thoroughly investigated and found suitable for the non-equilibrium conditions expected in the wave. Experiments were performed to verify the temperature measurement technique, to screen possible materials for surface initiation of the laser absorption wave and to attempt to initiate an absorption wave using the 1.5 kW carbon dioxide laser. The OLD technique was proven for air and for argon, but spark breakdown could not be produced in helium. It was not possible to initiate a laser absorption wave in mixtures of water and helium or water and argon using the 1.5 kW laser, a result which was consistent with the model prediction.

  1. Cavity Ring-Down Absorption of O2 in Air as a Temperature Sensor for an Open and a Cryogenic Optical Cavity.

    PubMed

    Nyaupane, Parashu R; Perez-Delgado, Yasnahir; Camejo, David; Wright, Lesley M; Manzanares, Carlos E

    2017-05-01

    The A-band of oxygen has been measured at low resolution at temperatures between 90 K and 373 K using the phase shift cavity ring down (PS-CRD) technique. For temperatures between 90 K and 295 K, the PS-CRD technique presented here involves an optical cavity attached to a cryostat. The static cell and mirrors of the optical cavity are all inside a vacuum chamber at the same temperature of the cryostat. The temperature of the cell can be changed between 77 K and 295 K. For temperatures above 295 K, a hollow glass cylindrical tube without windows has been inserted inside an optical cavity to measure the temperature of air flowing through the tube. The cavity consists of two highly reflective mirrors which are mounted parallel to each other and separated by a distance of 93 cm. In this experiment, air is passed through a heated tube. The temperature of the air flowing through the tube is determined by measuring the intensity of the oxygen absorption as a function of the wavenumber. The A-band of oxygen is measured between 298 K and 373 K, with several air flow rates. To obtain the temperature, the energy of the lower rotational state for seven selected rotational transitions is linearly fitted to a logarithmic function that contains the relative intensity of the rotational transition, the initial and final rotational quantum numbers, and the energy of the transition. Accuracy of the temperature measurement is determined by comparing the calculated temperature from the spectra with the temperature obtained from a calibrated thermocouple inserted at the center of the tube. This flowing air temperature sensor will be used to measure the temperatures of cooling air at the input (cold air) and output (hot air) after cooling the blades of a laboratory gas turbine. The results could contribute to improvements in turbine blade cooling design.

  2. Sound absorption of a new oblique-section acoustic metamaterial with nested resonator

    NASA Astrophysics Data System (ADS)

    Gao, Nansha; Hou, Hong; Zhang, Yanni; Wu, Jiu Hui

    2018-02-01

    This study designs and investigates high-efficiency sound absorption of new oblique-section nested resonators. Impedance tube experiment results show that different combinations of oblique-section nest resonators have tunable low-frequency bandwidth characteristics. The sound absorption mechanism is due to air friction losses in the slotted region and the sample structure resonance. The acousto-electric analogy model demonstrates that the sound absorption peak and bandwidth can be modulated over an even wider frequency range by changing the geometric size and combinations of structures. The proposed structure can be easily fabricated and used in low-frequency sound absorption applications.

  3. Oxygen production by molten alkali metal salts using multiple absorption-desorption cycles

    DOEpatents

    Cassano, Anthony A.

    1985-01-01

    A continuous chemical air separation is performed wherein oxygen is recovered with a molten alkali metal salt oxygen acceptor in a series of absorption zones which are connected to a plurality of desorption zones operated in separate parallel cycles with the absorption zones. A greater recovery of high pressure oxygen is achieved at reduced power requirements and capital costs.

  4. Triatoma maculata colonises urban domicilies in Boa Vista, Roraima, Brazil.

    PubMed

    Ricardo-Silva, Alice; Gonçalves, Teresa Cristina Monte; Luitgards-Moura, José Francisco; Lopes, Catarina Macedo; Silva, Silvano Pedrosa da; Bastos, Amanda Queiroz; Vargas, Nathalia Coelho; Freitas, Maria-Rosa Goreti

    2016-11-01

    During a medical entomology course in Boa Vista, Roraima, colonies of Triatoma maculata closely associated with pigeon nests were observed in concrete air-conditioner box located on the external plastered and cemented walls of a modern brick-built apartment block. In only one eight-hole ceramic brick, located inside one air-conditioner box, 127 specimens of T. maculata were collected. T. maculata is a recognised vector of Trypanosoma cruzi in the surrounding area and its domiciliation increases the risk of Chagas disease transmission.

  5. Infrared band absorptance correlations and applications to nongray radiation. [mathematical models of absorption spectra for nongray atmospheres in order to study air pollution

    NASA Technical Reports Server (NTRS)

    Tiwari, S. N.; Manian, S. V. S.

    1976-01-01

    Various mathematical models for infrared radiation absorption spectra for atmospheric gases are reviewed, and continuous correlations for the total absorptance of a wide band are presented. Different band absorptance correlations were employed in two physically realistic problems (radiative transfer in gases with internal heat source, and heat transfer in laminar flow of absorbing-emitting gases between parallel plates) to study their influence on final radiative transfer results. This information will be applied to the study of atmospheric pollutants by infrared radiation measurement.

  6. UV-responsive nano-sponge for oil absorption and desorption

    PubMed Central

    Kim, Do Hyun; Jung, Min Chan; Cho, So-Hye; Kim, Sang Hoon; Kim, Ho-Young; Lee, Heon Ju; Oh, Kyu Hwan; Moon, Myoung-Woon

    2015-01-01

    Controlled surface wettability for oil has been intensively studied to remove industrial oil waste or oil spill pollution from seas or rivers. In particular, external stimuli-induced special wetting materials, such as photo-responsive TiO2, have attracted considerable attention for oil-water separation. In this study, a novel method is reported to fabricate a nano-sponge which is composed of hydrophobic hydrocarbon and hydrophilic TiO2 nanoparticles for oil absorption or desorption that are responsive to UV irradiation. The hydrocarbon in the nano-sponge could selectively absorb oil from water, whereas the absorbed oil is released into the water by TiO2 in response to UV irradiation. The nano-sponge functionalized porous polydimethylsiloxane released more than 98% of the absorbed crude oil with UV irradiation and air-bubbling. It could be continuously reused while maintaining a high absorption capacity and desorption efficiency without incurring secondary air or water pollution. This smart oil absorption/desorption methodology with excellent selectivity and recyclability with almost perfect removal of absorbed oil can be applied for oil-water separation, oil spill cleanup and reuse of spilled oil. PMID:26260470

  7. Control of acoustic absorption in one-dimensional scattering by resonant scatterers

    NASA Astrophysics Data System (ADS)

    Merkel, A.; Theocharis, G.; Richoux, O.; Romero-García, V.; Pagneux, V.

    2015-12-01

    We experimentally report perfect acoustic absorption through the interplay of the inherent losses and transparent modes with high Q factor. These modes are generated in a two-port, one-dimensional waveguide, which is side-loaded by isolated resonators of moderate Q factor. In symmetric structures, we show that in the presence of small inherent losses, these modes lead to coherent perfect absorption associated with one-sided absorption slightly larger than 0.5. In asymmetric structures, near perfect one-sided absorption is possible (96%) with a deep sub-wavelength sample ( λ / 28 , where λ is the wavelength of the sound wave in the air). The control of strong absorption by the proper tuning of the radiation leakage of few resonators with weak losses will open possibilities in various wave-control devices.

  8. Oxygen production by molten alkali metal salts using multiple absorption-desorption cycles

    DOEpatents

    Cassano, A.A.

    1985-07-02

    A continuous chemical air separation is performed wherein oxygen is recovered with a molten alkali metal salt oxygen acceptor in a series of absorption zones which are connected to a plurality of desorption zones operated in separate parallel cycles with the absorption zones. A greater recovery of high pressure oxygen is achieved at reduced power requirements and capital costs. 3 figs.

  9. Atmospheric absorption of terahertz radiation and water vapor continuum effects

    NASA Astrophysics Data System (ADS)

    Slocum, David M.; Slingerland, Elizabeth J.; Giles, Robert H.; Goyette, Thomas M.

    2013-09-01

    The water vapor continuum absorption spectrum was investigated using Fourier Transform Spectroscopy. The transmission of broadband terahertz radiation from 0.300 to 1.500 THz was recorded for multiple path lengths and relative humidity levels. The absorption coefficient as a function of frequency was determined and compared with theoretical predictions and available water vapor absorption data. The prediction code is able to separately model the different parts of atmospheric absorption for a range of experimental conditions. A variety of conditions were accurately modeled using this code including both self and foreign gas broadening for low and high water vapor pressures for many different measurement techniques. The intensity and location of the observed absorption lines were also in good agreement with spectral databases. However, there was a discrepancy between the resonant line spectrum simulation and the observed absorption spectrum in the atmospheric transmission windows caused by the continuum absorption. A small discrepancy remained even after using the best available data from the literature to account for the continuum absorption. From the experimental and resonant line simulation spectra the air-broadening continuum parameter was calculated and compared with values available in the literature.

  10. Remote Sensing of Aerosol and Non-Aerosol Absorption

    NASA Technical Reports Server (NTRS)

    Kaufman, Y. J.; Dubovik, O.; Holben, B. N.; Remer, L. A.; Tanre, D.; Lau, William K. M. (Technical Monitor)

    2001-01-01

    Remote sensing of aerosol from the new satellite instruments (e.g. MODIS from Terra) and ground based radiometers (e.g. the AERONET) provides the opportunity to measure the absorption characteristics of the ambient undisturbed aerosol in the entire atmospheric column. For example Landsat and AERONET data are used to measure spectral absorption of sunlight by dust from West Africa. Both Application of the Landsat and AERONET data demonstrate that Saharan dust absorption of solar radiation is several times smaller than the current international standards. This is due to difficulties of measuring dust absorption in situ, and due to the often contamination of dust properties by the presence of air pollution or smoke. We use the remotely sensed aerosol absorption properties described by the spectral sin le scattering albedo, together with statistics of the monthly optical thickness for the fine and coarse aerosol derived from the MODIS data. The result is an estimate of the flux of solar radiation absorbed by the aerosol layer in different regions around the globe where aerosol is prevalent. If this aerosol forcing through absorption is not included in global circulation models, it may be interpreted as anomalous absorption in these regions. In a preliminary exercise we also use the absorption measurements by AERONET, to derive the non-aerosol absorption of the atmosphere in cloud free conditions. The results are obtained for the atmospheric windows: 0.44 microns, 0.66 microns, 0.86 microns and 1.05 microns. In all the locations over the land and ocean that were tested no anomalous absorption in these wavelengths, was found within absorption optical thickness of +/- 0.005.

  11. Triatoma maculata colonises urban domicilies in Boa Vista, Roraima, Brazil

    PubMed Central

    Ricardo-Silva, Alice; Gonçalves, Teresa Cristina Monte; Luitgards-Moura, José Francisco; Lopes, Catarina Macedo; da Silva, Silvano Pedrosa; Bastos, Amanda Queiroz; Vargas, Nathalia Coelho; Freitas, Maria-Rosa Goreti

    2016-01-01

    During a medical entomology course in Boa Vista, Roraima, colonies of Triatoma maculata closely associated with pigeon nests were observed in concrete air-conditioner box located on the external plastered and cemented walls of a modern brick-built apartment block. In only one eight-hole ceramic brick, located inside one air-conditioner box, 127 specimens of T. maculata were collected. T. maculata is a recognised vector of Trypanosoma cruzi in the surrounding area and its domiciliation increases the risk of Chagas disease transmission. PMID:27759767

  12. Subwavelength total acoustic absorption with degenerate resonators

    NASA Astrophysics Data System (ADS)

    Yang, Min; Meng, Chong; Fu, Caixing; Li, Yong; Yang, Zhiyu; Sheng, Ping

    2015-09-01

    We report the experimental realization of perfect sound absorption by sub-wavelength monopole and dipole resonators that exhibit degenerate resonant frequencies. This is achieved through the destructive interference of two resonators' transmission responses, while the matching of their averaged impedances to that of air implies no backscattering, thereby leading to total absorption. Two examples, both using decorated membrane resonators (DMRs) as the basic units, are presented. The first is a flat panel comprising a DMR and a pair of coupled DMRs, while the second one is a ventilated short tube containing a DMR in conjunction with a sidewall DMR backed by a cavity. In both examples, near perfect absorption, up to 99.7%, has been observed with the airborne wavelength up to 1.2 m, which is at least an order of magnitude larger than the composite absorber. Excellent agreement between theory and experiment is obtained.

  13. Performance evaluation of the Solar Building Test Facility

    NASA Technical Reports Server (NTRS)

    Jensen, R. N.

    1981-01-01

    The general performance of the NASA Solar Building Test Facility (SBTF) and its subsystems and components over a four year operational period is discussed, and data are provided for a typical one year period. The facility consists of a 4645 sq office building modified to accept solar heated water for operation of an absorption air conditioner and a baseboard heating system. An adjoining 1176 sq solar flat plate collector field with a 114 cu tank provides the solar heated water. The solar system provided 57 percent of the energy required for heating and cooling on an annual basis. The average efficiency of the solar collectors was 26 percent over a one year period.

  14. [Determination of sulfur in plant using a high-resolution continuum source atomic absorption spectrometer].

    PubMed

    Wang, Yu; Li, Jia-xi

    2009-05-01

    A method for the analysis of sulfur (S) in plant by molecular absorption of carbon monosulfide (CS) using a high-resolution continuum source atomic absorption spectrometer (CS AAS) with a fuel-rich air/acetylene flame has been devised. The strong CS absorption band was found around 258 nm. The half-widths of some absorption bands were of the order of picometers, the same as the common atomic absorption lines. The experimental procedure in this study provided optimized instrumental conditions (the ratio of acetylene to air, the burner height) and parameters, and researched the spectral interferences and chemical interferences. The influence of the organic solvents on the CS absorption signals and the different digestion procedures for the determination of sulfur were also investigated. The limit of detection achieved for sulfur was 14 mg x L(-1), using the CS wavelength of 257. 961 nm and a measurement time of 3 s. The accuracy and precision were verified by analysis of two plant standard reference materials. The major applications of this method have been used for the determination of sulfur in plant materials, such as leaves. Compared to the others, this method for the analysis of sulfur is rapid, easy and simple for sulfur determination in plant.

  15. Laser Radar Study Using Resonance Absorption for Remote Detection Of Air Pollutants

    NASA Technical Reports Server (NTRS)

    Igarashi, Takashi

    1973-01-01

    A laser radar using resonance absorption has an advantage of increased detection range and sensitivity compared with that achieved by Raman or resonance back scattering. In this paper, new laser radar system using resonance absorption is proposed and results obtained from this laser radar system are discussed. NO2, SO2 gas has an absorption spectrum at 4500 A and 3000 A respectively as shown in Fig. 1. A laser light including at least a set of an absorption peak (lambda)1 and a valley (lambda)2 is emitted into a pollutant atmosphere. The light reflected with a topographical reflector or an atmospheric Mie scattering as distributed reflectors is received and divided into two wavelength components (lambda)1 and (lambda)2. The laser radar system used in the investigation is shown in Fig', 2 and consists of a dye laser transmitter, an optical receiver with a special monochrometer and a digital processer. Table 1 shows the molecular constants of NO2, and SO2 and the dye laser used in this experiment. In this system, the absolute concentration of the pollutant gas can be measured in comparison with a standard gas cell. The concentration of NO2, SO2 as low as 0.1 ppm have been measured at 100 m depth resolution. For a 1 mJ laser output, the observable range of this system achieved up to 300 m using the distributed Mie reflector. The capability and technical limitation of the system will be discussed in detail.

  16. Differential Absorption Lidar (DIAL) Measurements from Air and Space

    NASA Technical Reports Server (NTRS)

    Browell, E. V.; Ismail, S.; Grant, W. B.

    1998-01-01

    Differential absorption lidar (DIAL) systems have been used for the measurement of ozone, water vapor, and aerosols from aircraft platforms for over 18 years, yielding new insights into atmospheric chemistry, composition, and dynamics in large-scale field experiments conducted all over the world. The successful deployment of the lidar in-space technology experiment (LITE) in September 1994 demonstrated that space-based lidars can also collect valuable information on the global atmosphere. This paper reviews some of the contributions of the NASA Langley Research Center's airborne ozone and water vapor DIAL systems and space-based LITE system to the understanding of the atmosphere and discusses the feasibility and advantages of putting DIAL systems in space for routine atmospheric measurements of ozone and/or water vapor and aerosols and clouds. The technology and applications of the differential absorption lidar (DIAL) technique have progressed significantly since the first DIAL measurements of Schotland, and airborne DIAL measurements of ozone and water vapor are frequently being made in a wide range of field experiments. In addition, plans are underway to develop DIAL systems for use on satellites for continuous global measurements. This paper will highlight the history of airborne lidar and DIAL systems, summarize the major accomplishments of the NASA Langley DIAL program, and discuss specifications and goals for DIAL systems in space.

  17. Extremely Low Frequency Electromagnetic Field from Convective Air Warming System on Temperature Selection and Distance.

    PubMed

    Cho, Kwang Rae; Kim, Myoung-Hun; Ko, Myoung Jin; Jung, Jae Wook; Lee, Ki Hwa; Park, Yei-Heum; Kim, Yong Han; Kim, Ki Hoon; Kim, Jin Soo

    2014-12-01

    Hypothermia generates potentially severe complications in operating or recovery room. Forced air warmer is effective to maintain body temperature. Extremely low frequency electromagnetic field (ELF-EMF) is harmful to human body and mainly produced by electronic equipment including convective air warming system. We investigated ELF-EMF from convective air warming device on various temperature selection and distance for guideline to protect medical personnel and patients. The intensity of ELF-EMF was measured as two-second interval for five minutes on various distance (0.1, 0.2, 0.3, 0.5 and 1meter) and temperature selection (high, medium, low and ambient). All of electrical devices were off including lamp, computer and air conditioner. Groups were compared using one-way ANOVA. P<0.05 was considered significant. Mean values of ELF-EMF on the distance of 30 cm were 18.63, 18.44, 18.23 and 17.92 milligauss (mG) respectively (high, medium, low and ambient temperature set). ELF-EMF of high temperature set was higher than data of medium, low and ambient set in all the distances. ELF-EMF from convective air warming system is higher in condition of more close location and higher temperature. ELF-EMF within thirty centimeters exceeds 2mG recommended by Swedish TCO guideline.

  18. Moisture absorption and bakeout characteristics of rigid-flexible multilayer printed wiring boards

    NASA Astrophysics Data System (ADS)

    Lula, J. W.

    1991-01-01

    Moisture absorption and bakeout characteristics of rigid flexible printed wiring boards were determined. It was found that test specimens had absorbed 0.95 weight percent moisture when equilibrated to a 50 percent RH, 25 C environment. Heating those equilibrated specimens in a 120 C static air oven removed 92 percent of this absorbed moisture in 24 h. Heating the samples in a 80 C static air oven removed only 64 percent of the absorbed moisture at the end of 24 h. A 120 C vacuum bake removed moisture at essentially the same rate with parylene slowed the absorption rate by approximately 50 percent but did not appreciably affect the equilibrium moisture content or the drying rate.

  19. Investigating the variability in brown carbon light-absorption properties

    NASA Astrophysics Data System (ADS)

    Saleh, R.; Cheng, Z.; Atwi, K.

    2017-12-01

    Combustion of biomass fuels contributes a significant portion of brown carbon (BrC), the light-absorbing fraction of organic aerosols. BrC exhibits highly variable light-absorption properties, with imaginary part of the refractive indices (k) reported in the literature varying over two orders of magnitude. This high variability in k is attributed to the chaotic nature of combustion; however, there is a major gap in the fundamental understanding of this variability. To address this gap, we hypothesize that BrC is comprised of black carbon (BC) precursors whose transformation to BC has not seen fruition. Depending on the combustion conditions, these BC precursors exhibit different maturity levels which dictate their light-absorption properties (k). The more mature are the precursors, the more absorptive (or BC-like) they are. Therefore, k of BrC obtained from a certain measurement depends on the specific combustion conditions associated with the measurement, leading to the aforementioned variability in the literature. To test this hypothesis, we performed controlled combustion experiments in which the combustion conditions (temperature and air/fuel ratio) were varied and k was retrieved from real-time multi-wavelength light-absorption measurements at each condition. We used benzene, the inception of which during combustion is the initial critical step leading to BC formation, as a model fuel. By varying the combustion conditions from relatively inefficient (low temperature and/or air/fuel ratio) to relatively efficient (high temperature and/or air/fuel ratio), we isolated BrC components with progressively increasing k, spanning the wide range reported in the literature. We also performed thermodenuder measurements to constrain the volatility of the BrC, as well as laser desorption ionization mass spectrometry analysis to constrain its molecular mass. We found that as the combustion conditions approached the BC-formation threshold, the increase in k was associated

  20. Effect of air velocity and direction for indirect evaporative cooling in tropical area

    NASA Astrophysics Data System (ADS)

    Ayodha Ajiwiguna, Tri; Nugraha Rismi, Fadhlin; Ramdlan Kirom, Mukhammad

    2017-06-01

    In this research, experimental study of heat absorption rate caused by indirect evaporative cooling is performed by varying the velocity and direction of air. The ambient is at average temperature and relative humidity of 28.7 °C and 78% respectively. The experiment is conducted by attaching wet medium on the top of material reference plate with the dimension of 14 x 8 cm with 5 mm thickness. To get evaporative cooling effect, the air flow is directed to the wet medium with velocity from 1.6 m/s to 3.4 m/s with the increment of 0.2 m/s. The direction of air is set 0° (parallel), 45° (inclined), and 90° (perpendicular) to the wet medium surface. While the experiment is being performed, the air temperature, top and bottom of plate temperature are measured simultaneously after steady state condition is established. Based on the measurement result, heat absorption is calculated by analysing the heat conduction on the material reference. The result shows that the heat absorption rate is increased by higher velocity. Perpendicular direction of air flow results the highest cooling capacity compared with other direction. The maximum heat absorption rate is achieved at 13.9 Watt with 3.4 m/s velocity and perpendicular direction of air.

  1. Electric and hybrid vehicle environmental control subsystem study

    NASA Technical Reports Server (NTRS)

    Heitner, K. L.

    1980-01-01

    An environmental control subsystem (ECS) in electric and hybrid vehicles is studied. A combination of a combustion heater and gasoline engine (Otto cycle) driven vapor compression air conditioner is selected. The combustion heater, the small gasoline engine, and the vapor compression air conditioner are commercially available. These technologies have good cost and performance characteristics. The cost for this ECS is relatively close to the cost of current ECS's. Its effect on the vehicle's propulsion battery is minimal and the ECS size and weight do not have significant impact on the vehicle's range.

  2. Fungi of the house dust in Riyadh, Saudi Arabia.

    PubMed

    Saad, R R; el-Gindy, A A

    1990-01-01

    30 species belonging to 18 genera were isolated from floor dust of 30 homes in Riyadh. Out of them 16 species and 10 genera were isolated from dust of air conditioners of the same homes. The most common genera in floor dust were Aspergillus, Penicillium and Cladosporium. Aspergillus repens, A. amstelodami, A. versicolor, A. fumigatus, Penicillium purpurogenum, P. crustosum, Cladosporium cladosporoides and C. herbarum were frequently isolated. The most abundant genera in air conditioner dust were Aspergillus and Penicillium. Aspergillus fumigatus, A. ochraceus, A. terreus, Penicillium oxalicium and P. crustosum were most frequent species.

  3. Light absorption enhancement of black carbon from urban haze in Northern China winter.

    PubMed

    Chen, Bing; Bai, Zhe; Cui, Xinjuan; Chen, Jianmin; Andersson, August; Gustafsson, Örjan

    2017-02-01

    Atmospheric black carbon (BC) is an important pollutant for both air quality and Earth's energy balance. Estimates of BC climate forcing remain highly uncertain, e.g., due to the mixing with non-absorbing components. Non-absorbing aerosols create a coating on BC and may thereby act as a lens which may enhance the light absorption. However, this absorption enhancement is poorly constrained. To this end a two-step solvent dissolution protocol was employed to remove both organic and inorganic coatings, and then investigate their effects on BC light absorption. Samples were collected at a severely polluted urban area, Jinan, in the North China Plain (NCP) during February 2014. The BC mass absorption cross-section (MAC) was measured for the aerosol samples before and after the solvent-decoating treatment, and the enhancement of MAC (E MAC ) from the coating effect was defined as the ratio. A distinct diurnal pattern for the enhancement was observed, with E MAC 1.3 ± 0.3 (1 S.D.) in the morning, increasing to 2.2 ± 1.0 in the afternoon, after that dropping to 1.5 ± 0.8 in the evening-night. The BC absorption enhancement primarily was associated with urban-scale photochemical production of nitrate and sulfate aerosols. In addition to that, regional-scale haze plume with increasing sulfate levels strengthened the absorption enhancement. These observations offer direct evidence for an increased absorption enhancement of BC due to severe air pollution in China. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. Sound absorption of a porous material with a perforated facing at high sound pressure levels

    NASA Astrophysics Data System (ADS)

    Peng, Feng

    2018-07-01

    A semi-empirical model is proposed to predict the sound absorption of an acoustical unit consisting of a rigid-porous material layer with a perforated facing under the normal incidence at high sound pressure levels (SPLs) of pure tones. The nonlinearity of the perforated facing and the porous material, and the interference between them are considered in the model. The sound absorptive performance of the acoustical unit is tested at different incident SPLs and in three typical configurations: 1) when the perforated panel (PP) directly contacts with the porous layer, 2) when the PP is separated from the porous layer by an air gap and 3) when an air cavity is set between the porous material and the hard backing wall. The test results agree well with the corresponding theoretical predictions. Moreover, the results show that the interference effect is correlated to the width of the air gap between the PP and the porous layer, which alters not only the linear acoustic impedance but also the nonlinear acoustic impedance of the unit and hence its sound absorptive properties.

  5. Absorption spectra of deuterated water at DF laser wavelengths.

    PubMed

    Bruce, C W; Jelinek, A V

    1982-11-15

    Absorption coefficients for deuterated water have been measured at twenty-two deuterium fluoride (DF) laser wavelengths and presented for atmospheric conditions classified as midlatitude-summer (14.3 T water vapor, standard temperature, and pressure). The HDO vapor was produced from a liquid mixture of H(2)O and D(2)O. The proportions of the resulting equilibrium mixture involving these constituents and HDO were calculated using previously measured constants and produced strong HDO absorption at the 3.5-4.1-microm DF laser wavelengths relative to those of the H(2)O and D(2)O vapors. Predicted and measured pressure dependencies at constant mixing ratios are compared for several laser wavelengths having strong HDO absorption. Absorption coefficients are in fairly close agreement with those of the current Air Force Geophysical Laboratory line-by-line model for standard temperature and pressure conditions. At lower total pressures, the comparison is less satisfactory and suggests inaccurate line parameters in the predictive data base.

  6. 78 FR 63183 - Information Collection Request Submitted to OMB for Review and Approval; Comment Request; Mobile...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-10-23

    ... of air conditioning systems and recovery/recycling equipment. Form Numbers: None. Respondents... automotive repair shops, automotive repair shops not elsewhere classified, including air conditioning and... Request Submitted to OMB for Review and Approval; Comment Request; Mobile Air Conditioner Retrofitting...

  7. Isothermal absorption of soluble gases by atmospheric nanoaerosols

    NASA Astrophysics Data System (ADS)

    Elperin, T.; Fominykh, A.; Krasovitov, B.; Lushnikov, A.

    2013-01-01

    We investigate mass transfer during the isothermal absorption of atmospheric trace soluble gases by a single droplet whose size is comparable to the molecular mean free path in air at normal conditions. It is assumed that the trace reactant diffuses to the droplet surface and then reacts with the substances inside the droplet according to the first-order rate law. Our analysis applies a flux-matching theory of transport processes in gases and assumes constant thermophysical properties of the gases and liquids. We derive an integral equation of Volterra type for the transient molecular flux density to a liquid droplet and solve it numerically. Numerical calculations are performed for absorption of sulfur dioxide (SO2), dinitrogen trioxide (N2O3), and chlorine (Cl2) by liquid nanoaerosols accompanied by chemical dissociation reaction. It is shown that during gas absorption by nanoaerosols, the kinetic effects play a significant role, and neglecting kinetic effects leads to a significant overestimation of the soluble gas flux into a droplet during the entire period of gas absorption.

  8. Isothermal absorption of soluble gases by atmospheric nanoaerosols.

    PubMed

    Elperin, T; Fominykh, A; Krasovitov, B; Lushnikov, A

    2013-01-01

    We investigate mass transfer during the isothermal absorption of atmospheric trace soluble gases by a single droplet whose size is comparable to the molecular mean free path in air at normal conditions. It is assumed that the trace reactant diffuses to the droplet surface and then reacts with the substances inside the droplet according to the first-order rate law. Our analysis applies a flux-matching theory of transport processes in gases and assumes constant thermophysical properties of the gases and liquids. We derive an integral equation of Volterra type for the transient molecular flux density to a liquid droplet and solve it numerically. Numerical calculations are performed for absorption of sulfur dioxide (SO(2)), dinitrogen trioxide (N(2)O(3)), and chlorine (Cl(2)) by liquid nanoaerosols accompanied by chemical dissociation reaction. It is shown that during gas absorption by nanoaerosols, the kinetic effects play a significant role, and neglecting kinetic effects leads to a significant overestimation of the soluble gas flux into a droplet during the entire period of gas absorption.

  9. 24 CFR 3280.714 - Appliances, cooling.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... Systems § 3280.714 Appliances, cooling. (a) Every air conditioning unit or a combination air conditioning...) Mechanical air conditioners shall be rated in accordance with the ARI Standard 210/240-89 Unitary Air Conditioning and Air Source Unitary Heat Pump Equipment and certified by ARI or other nationally recognized...

  10. 24 CFR 3280.714 - Appliances, cooling.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... Systems § 3280.714 Appliances, cooling. (a) Every air conditioning unit or a combination air conditioning...) Mechanical air conditioners shall be rated in accordance with the ARI Standard 210/240-89 Unitary Air Conditioning and Air Source Unitary Heat Pump Equipment and certified by ARI or other nationally recognized...

  11. Calculation tool for transported geothermal energy using two-step absorption process

    DOE Data Explorer

    Kyle Gluesenkamp

    2016-02-01

    This spreadsheet allows the user to calculate parameters relevant to techno-economic performance of a two-step absorption process to transport low temperature geothermal heat some distance (1-20 miles) for use in building air conditioning. The parameters included are (1) energy density of aqueous LiBr and LiCl solutions, (2) transportation cost of trucking solution, and (3) equipment cost for the required chillers and cooling towers in the two-step absorption approach. More information is available in the included public report: "A Technical and Economic Analysis of an Innovative Two-Step Absorption System for Utilizing Low-Temperature Geothermal Resources to Condition Commercial Buildings"

  12. Performance characteristic of hybrid cooling system based on cooling pad and evaporator

    NASA Astrophysics Data System (ADS)

    Yoon, J. I.; Son, C. H.; Choi, K. H.; Kim, Y. B.; Sung, Y. H.; Roh, S. J.; Kim, Y. M.; Seol, S. H.

    2018-01-01

    In South Korea, most of domestic animals such as pigs and chickens might die due to thermal diseases if they are exposed to the high temperature consistently. In order to save them from the heat wave, numerous efforts have been carried out: installing a shade net, adjusting time of feeding, spraying mist and setting up a circulation fan. However, these methods have not shown significant improvements. Thus, this study proposes a hybrid cooling system combining evaporative cooler and air-conditioner in order to resolve the conventional problems caused by the high temperature in the livestock industry. The problem of cooling systems using evaporative cooling pads is that they are not effective for eliminating huge heat load due to their limited capacity. And, temperature of the supplied air cannot be low enough compared to conventional air-conditioning systems. On the other hand, conventional air-conditioning systems require relatively expensive installation cost, and high operating cost compared to evaporative cooling system. The hybrid cooling system makes up for the lack of cooling capacity of the evaporative cooler by employing the conventional air-conditioner. Additionally, temperature of supplied air can be lowered enough. In the hybrid cooling system, induced air by a fan is cooled by the evaporation of water in the cooling pad, and it is cooled again by an evaporator in the air-conditioner. Therefore, the more economical operation is possible due to additionally obtained cooling capacity from the cooling pads. Major results of experimental analysis of hybrid cooling system are as follows. The compressor power consumption of the hybrid cooling system is about 23% lower, and its COP is 17% higher than that of the conventional air-conditioners. Regarding the condition of changing ambient temperature, the total power consumption decreased by about 5% as the ambient temperature changed from 28.7°C to 31.7°C. Cooling capacity and COP also presented about 3% and 1

  13. The Gas-Absorption/Chemical-Reaction Method for Measuring Air-Water Interfacial Area in Natural Porous Media

    NASA Astrophysics Data System (ADS)

    Lyu, Ying; Brusseau, Mark L.; El Ouni, Asma; Araujo, Juliana B.; Su, Xiaosi

    2017-11-01

    The gas-absorption/chemical-reaction (GACR) method used in chemical engineering to quantify gas-liquid interfacial area in reactor systems is adapted for the first time to measure the effective air-water interfacial area of natural porous media. Experiments were conducted with the GACR method, and two standard methods (X-ray microtomographic imaging and interfacial partitioning tracer tests) for comparison, using model glass beads and a natural sand. The results of a series of experiments conducted under identical conditions demonstrated that the GACR method exhibited excellent repeatability for measurement of interfacial area (Aia). Coefficients of variation for Aia were 3.5% for the glass beads and 11% for the sand. Extrapolated maximum interfacial areas (Am) obtained with the GACR method were statistically identical to independent measures of the specific solid surface areas of the media. For example, the Am for the glass beads is 29 (±1) cm-1, compared to 32 (±3), 30 (±2), and 31 (±2) cm-1 determined from geometric calculation, N2/BET measurement, and microtomographic measurement, respectively. This indicates that the method produced accurate measures of interfacial area. Interfacial areas determined with the GACR method were similar to those obtained with the standard methods. For example, Aias of 47 and 44 cm-1 were measured with the GACR and XMT methods, respectively, for the sand at a water saturation of 0.57. The results of the study indicate that the GACR method is a viable alternative for measuring air-water interfacial areas. The method is relatively quick, inexpensive, and requires no specialized instrumentation compared to the standard methods.

  14. Instrumentation for air quality measurements.

    NASA Technical Reports Server (NTRS)

    Loewenstein, M.

    1973-01-01

    Comparison of the new generation of air quality monitoring instruments with some more traditional methods. The first generation of air quality measurement instruments, based on the use of oxidant coulometric cells, nitrogen oxide colorimetry, carbon monoxide infrared analyzers, and other types of detectors, is compared with new techniques now coming into wide use in the air monitoring field and involving the use of chemiluminescent reactions, optical absorption detectors, a refinement of the carbon monoxide infrared analyzer, electrochemical cells based on solid electrolytes, and laser detectors.

  15. Inertial impaction air sampling device

    DOEpatents

    Dewhurst, Katharine H.

    1990-01-01

    An inertial impactor to be used in an air sampling device for collection of respirable size particles in ambient air which may include a graphite furnace as the impaction substrate in a small-size, portable, direct analysis structure that gives immediate results and is totally self-contained allowing for remote and/or personal sampling. The graphite furnace collects suspended particles transported through the housing by means of the air flow system, and these particles may be analyzed for elements, quantitatively and qualitatively, by atomic absorption spectrophotometry.

  16. 49 CFR Appendix H to Part 229 - Static Noise Test Protocols-In-Cab Static

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... normal operating temperature. (5) The heating, ventilation and air conditioning (HVAC) system or a dedicated heating or air conditioner system must be operating on high, and the vents must be open and...

  17. 49 CFR Appendix H to Part 229 - Static Noise Test Protocols-In-Cab Static

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... normal operating temperature. (5) The heating, ventilation and air conditioning (HVAC) system or a dedicated heating or air conditioner system must be operating on high, and the vents must be open and...

  18. 49 CFR Appendix H to Part 229 - Static Noise Test Protocols-In-Cab Static

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... normal operating temperature. (5) The heating, ventilation and air conditioning (HVAC) system or a dedicated heating or air conditioner system must be operating on high, and the vents must be open and...

  19. 49 CFR Appendix H to Part 229 - Static Noise Test Protocols-In-Cab Static

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... normal operating temperature. (5) The heating, ventilation and air conditioning (HVAC) system or a dedicated heating or air conditioner system must be operating on high, and the vents must be open and...

  20. LASER PLASMA AND LASER APPLICATIONS: Plasma transparency in laser absorption waves in metal capillaries

    NASA Astrophysics Data System (ADS)

    Anisimov, V. N.; Kozolupenko, A. P.; Sebrant, A. Yu

    1988-12-01

    An experimental investigation was made of the plasma transparency to heating radiation in capillaries when absorption waves propagated in these capillaries as a result of interaction with a CO2 laser pulse of 5-μs duration. When the length of the capillary was in excess of 20 mm, total absorption of the radiation by the plasma was observed at air pressures of 1-100 kPa. When the capillary length was 12 mm, a partial recovery of the transparency took place. A comparison was made with the dynamics and recovery of the plasma transparency when breakdown of air took place near the free surface.

  1. Effects of background noise on total noise annoyance

    NASA Technical Reports Server (NTRS)

    Willshire, K. F.

    1987-01-01

    Two experiments were conducted to assess the effects of combined community noise sources on annoyance. The first experiment baseline relationships between annoyance and noise level for three community noise sources (jet aircraft flyovers, traffic and air conditioners) presented individually. Forty eight subjects evaluated the annoyance of each noise source presented at four different noise levels. Results indicated the slope of the linear relationship between annoyance and noise level for the traffic noise was significantly different from that of aircraft and of air conditioner noise, which had equal slopes. The second experiment investigated annoyance response to combined noise sources, with aircraft noise defined as the major noise source and traffic and air conditioner noise as background noise sources. Effects on annoyance of noise level differences between aircraft and background noise for three total noise levels and for both background noise sources were determined. A total of 216 subjects were required to make either total or source specific annoyance judgements, or a combination of the two, for a wide range of combined noise conditions.

  2. Differential absorption lidar measurements of atmospheric temperature and pressure profiles

    NASA Technical Reports Server (NTRS)

    Korb, C. L.

    1981-01-01

    The theory and methodology of using differential absorption lidar techniques for the remote measurement of atmospheric pressure profiles, surface pressure, and temperature profiles from ground, air, and space-based platforms are presented. Pressure measurements are effected by means of high resolution measurement of absorption at the edges of the oxygen A band lines where absorption is pressure dependent due to collisional line broadening. Temperature is assessed using measurements of the absorption at the center of the oxygen A band line originating from a quantum state with high ground state energy. The population of the state is temperature dependent, allowing determination of the temperature through the Boltzmann term. The results of simulations of the techniques using Voigt profile and variational analysis are reported for ground-based, airborne, and Shuttle-based systems. Accuracies in the 0.5-1.0 K and 0.1-0.3% range are projected.

  3. Sound absorption of textile material using a microfibres resistive layer

    NASA Astrophysics Data System (ADS)

    Segura Alcaraz, M. P.; Bonet-Aracil, M.; Segura Alcaraz, J. G.; Montava Seguí, I.

    2017-10-01

    Acoustic comfort is a basic human need. One of the adverse effects of noise is its interference with speech discrimination. Textile materials are suitable to be used as sound absorptive materials and thus help to improve acoustic comfort in rooms. Micro-fibre fabrics can be considered as better sound absorbers than regular fibre fabrics mainly due to the higher surface of its fibres and bigger contact area with the air thus, allowing greater dissipation of sound energy. In this work, the use of a microfibre woven fabric as an upstream layer is analysed considering acoustic issues. Authors demonstrate it improves the sound absorption of a polyester nonwoven, resulting in a material suitable for absorption at the sound frequencies of the human voice.

  4. Inertial impaction air sampling device

    DOEpatents

    Dewhurst, K.H.

    1990-05-22

    An inertial impactor is designed which is to be used in an air sampling device for collection of respirable size particles in ambient air. The device may include a graphite furnace as the impaction substrate in a small-size, portable, direct analysis structure that gives immediate results and is totally self-contained allowing for remote and/or personal sampling. The graphite furnace collects suspended particles transported through the housing by means of the air flow system, and these particles may be analyzed for elements, quantitatively and qualitatively, by atomic absorption spectrophotometry. 3 figs.

  5. Inertial impaction air sampling device

    DOEpatents

    Dewhurst, K.H.

    1987-12-10

    An inertial impactor to be used in an air sampling device for collection of respirable size particles in ambient air which may include a graphite furnace as the impaction substrate in a small-size, portable, direct analysis structure that gives immediate results and is totally self-contained allowing for remote and/or personal sampling. The graphite furnace collects suspended particles transported through the housing by means of the air flow system, and these particles may be analyzed for elements, quantitatively and qualitatively, by atomic absorption spectrophotometry. 3 figs.

  6. Contribution of particulate brown carbon to light absorption in the rural and urban Southeast US

    NASA Astrophysics Data System (ADS)

    Devi, J. Jai; Bergin, Michael H.; Mckenzie, Michael; Schauer, James J.; Weber, Rodney J.

    2016-07-01

    Measurements of wavelength dependent aerosol light absorption coefficients were carried out as part of the Southern Oxidant and Aerosol Study (SOAS) during the summer of 2013 to determine the contribution of light absorbing organic carbon (BrC) to total aerosol light absorption in a rural location (Centreville, AL) and an urban area (Atlanta, GA). The light absorption coefficients in the near UV and visible wavelengths were measured for both ambient air, as well as ambient air heated in a thermal denuder to 200 °C to remove the semi-volatile organic compounds. Atlanta measurements show dominance of semi-volatile brown carbon with an average absorption angstrom exponent (AAE) of 1.4 before heating and about 1.0 after heating. In urban Atlanta, a decrease of about ∼35% in the light absorption coefficient at 370 nm after heating indicates that light absorbing organic compounds are a substantial fraction of the light absorption budget. Furthermore, a considerable increase in the fraction of light absorption by the semi-volatile aerosol occurs during the daytime, likely linked with photochemistry. Measurements at rural Centerville, on the other hand, do not show any major change in AAE with values before and after heating of 0.99 and 0.98, respectively. Overall the results suggest that photochemical aged urban emissions result in the presence of light absorbing BrC, while at rural locations which are dominated by aged aerosol and local biogenic emissions (based on measurements of Angstrom exponents) BrC does not significantly contribute to light absorption.

  7. 24 CFR 3280.805 - Branch circuits required.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... room air conditioner, etc.). There shall be one or more circuits of adequate rating in accordance with...)(5). For central air conditioning, see Article 440 of the National Electrical Code, NFPA No. 70-2005...

  8. Performance analysis of an air drier for a liquid dehumidifier solar air conditioning system

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Queiroz, A.G.; Orlando, A.F.; Saboya, F.E.M.

    1988-05-01

    A model was developed for calculating the operating conditions of a non-adiabatic liquid dehumidifier used in solar air conditioning systems. In the experimental facility used for obtaining the data, air and triethylene glycol circulate countercurrently outside staggered copper tubes which are the filling of an absorption tower. Water flows inside the copper tubes, thus cooling the whole system and increasing the mass transfer potential for drying air. The methodology for calculating the mass transfer coefficient is based on the Merkel integral approach, taking into account the lowering of the water vapor pressure in equilibrium with the water glycol solution.

  9. 40 CFR 86.158-00 - Supplemental Federal Test Procedures; overview.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Test Cycle. The test procedure for determining exhaust emissions with the air conditioner operating...) AIR PROGRAMS (CONTINUED) CONTROL OF EMISSIONS FROM NEW AND IN-USE HIGHWAY VEHICLES AND ENGINES... the aggressive driving (US06) and air conditioning (SC03) elements of the Supplemental Federal Test...

  10. 24 CFR 3280.714 - Appliances, cooling.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... any air conditioning or comfort-cooling system installed in a manufactured home shall employ a type of...) Every air conditioning unit or a combination air conditioning and heating unit shall be listed or... installed in accordance with the terms of its listing. (1) Mechanical air conditioners shall be rated in...

  11. MATHEMATICAL MODELING OF OZONE ABSORPTION IN THE LOWER RESPIRATORY TRACT

    EPA Science Inventory

    A mathematical O3 dosimetry model has been developed for simulating the local absorption of O3 in the lower respiratory tract (LRT) of animals and man. The model takes into account LRT anatomy, transport in the lumen and air spaces, transport and chemical reactions in the liquid ...

  12. Evidence for direct water absorption by shallow-rooted desert plants in desert-oasis ecotone, Northwest China

    NASA Astrophysics Data System (ADS)

    Fang, Jing

    2014-05-01

    Besides the absorption by roots from the soil substrate, it has long been known that plants exhibit alternative water-absorption strategies, particularly in drought-prone environments. For many tropical epiphytic orchids, air moisture can be absorbed directly by aerial roots. Some conifers are also found to utilize air moisture by foliar absorption during the summer fog season. However, few studies have been carried out on the atmospheric water vapor absorption by shallow-rooted desert plants. We conducted experiments in desert-oasis ecotone and investigated the effects of dew absorbed by three kinds of shallow-rooted seedlings on net photosynthesis rate, as well as on other water relations variables. Three kinds of typical shallow-rooted desert species (Bassia dasyphylla, Salsola collina and Corispermum declinatum) have been chosen and potted. Each species were subjected to contrasting watering regimes (normal and deficient) and different air moisture conditions (having dew and having no dew) for 10 weeks. Net photosynthesis rate was measured on six occasions during the study. Other water relations variables (midday shoot water potential, relative water content, stomatal conductance) were also measured. Under the dew conditions, average net photosynthesis rate, shoot water potential, leaf relative water content and stomatal conductance increased, with greater responses observed for plants subjected to a deficient watering regime than for well-watered plants. These results indicated dew occurred in arid region could be utilized through foliar absorption by some shallow-rooted plants, and for the shallow-rooted plants, the presence of dew could significantly relieve the deficit of water in water-stressed regime.

  13. 47. BASE OF UMBILICAL MAST, WITH ELECTRICAL POWER CABLES ON ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    47. BASE OF UMBILICAL MAST, WITH ELECTRICAL POWER CABLES ON LEFT; AIR-CONDITIONER DUCTS ON RIGHT - Vandenberg Air Force Base, Space Launch Complex 3, Launch Pad 3 East, Napa & Alden Roads, Lompoc, Santa Barbara County, CA

  14. Markedly enhanced absorption and direct radiative forcing of black carbon under polluted urban environments

    PubMed Central

    Peng, Jianfei; Hu, Min; Guo, Song; Du, Zhuofei; Zheng, Jing; Shang, Dongjie; Levy Zamora, Misti; Zeng, Limin; Shao, Min; Wu, Yu-Sheng; Zheng, Jun; Wang, Yuan; Glen, Crystal R.; Collins, Donald R.; Molina, Mario J.; Zhang, Renyi

    2016-01-01

    Black carbon (BC) exerts profound impacts on air quality and climate because of its high absorption cross-section over a broad range of electromagnetic spectra, but the current results on absorption enhancement of BC particles during atmospheric aging remain conflicting. Here, we quantified the aging and variation in the optical properties of BC particles under ambient conditions in Beijing, China, and Houston, United States, using a novel environmental chamber approach. BC aging exhibits two distinct stages, i.e., initial transformation from a fractal to spherical morphology with little absorption variation and subsequent growth of fully compact particles with a large absorption enhancement. The timescales to achieve complete morphology modification and an absorption amplification factor of 2.4 for BC particles are estimated to be 2.3 h and 4.6 h, respectively, in Beijing, compared with 9 h and 18 h, respectively, in Houston. Our findings indicate that BC under polluted urban environments could play an essential role in pollution development and contribute importantly to large positive radiative forcing. The variation in direct radiative forcing is dependent on the rate and timescale of BC aging, with a clear distinction between urban cities in developed and developing countries, i.e., a higher climatic impact in more polluted environments. We suggest that mediation in BC emissions achieves a cobenefit in simultaneously controlling air pollution and protecting climate, especially for developing countries. PMID:27035993

  15. Performance and economic enhancement of cogeneration gas turbines through compressor inlet air cooling

    NASA Astrophysics Data System (ADS)

    Delucia, M.; Bronconi, R.; Carnevale, E.

    1994-04-01

    Gas turbine air cooling systems serve to raise performance to peak power levels during the hot months when high atmospheric temperatures cause reductions in net power output. This work describes the technical and economic advantages of providing a compressor inlet air cooling system to increase the gas turbine's power rating and reduce its heat rate. The pros and cons of state-of-the-art cooling technologies, i.e., absorption and compression refrigeration, with and without thermal energy storage, were examined in order to select the most suitable cooling solution. Heavy-duty gas turbine cogeneration systems with and without absorption units were modeled, as well as various industrial sectors, i.e., paper and pulp, pharmaceuticals, food processing, textiles, tanning, and building materials. The ambient temperature variations were modeled so the effects of climate could be accounted for in the simulation. The results validated the advantages of gas turbine cogeneration with absorption air cooling as compared to other systems without air cooling.

  16. [Microbial air monitoring in operating theatre: active and passive samplings].

    PubMed

    Pasquarella, C; Masia, M D; Nnanga, Nga; Sansebastiano, G E; Savino, A; Signorelli, C; Veronesi, L

    2004-01-01

    Microbial air contamination was evaluated in 11 operating theatres using active and passive samplings. SAS (Surface Air System) air sampling was used to evaluate cfu/m3 and settle plates were used to measure the index of microbial air contamination (IMA). Samplings were performed at the same time on three different days, at three different times (before, during and after the surgical activity). Two points were monitored (patient area and perimeter of the operating theatre). Moreover, the cfu/m3 were evaluated at the air inlet of the conditioner system. 74.7% of samplings performed at the air inlet and 66.7% of the samplings performed at the patient area before the beginning of the surgical activity (at rest) exceeded the 35 cfu/m3 used as threshold value. 100% of IMA values exceeded the threshold value of 5. Using both active and passive sampling, the microbial contamination was shown to increase significantly during activity. The cfu values were higher at the patient area than at the perimeter of the operating theatre. Mean values of the cfu/m3 during activity at the patient area ranged from a minimum of 61+/-41 cfu/m3 to a maximum of 242+/-136 cfu/m3; IMA values ranged from a minimum of 19+/-10 to a maximum of 129+/-60. 15.2% of samplings performed at the patient area using SAS and 75.8% of samplings performed using settle plates exceeded the threshold values of 180 cfu/m3 and 25 respectively, with a significant difference of the percentages. The highest values were found in the operating theatre with inadequate structural and managerial conditions. These findings confirm that the microbiological quality of air may be considered a mirror of the hygienic conditions of the operating theatre. Settle plates proved to be more sensitive in detecting the increase of microbial air contamination related to conditions that could compromise the quality of the air in operating theatres.

  17. Modification of pure oxygen absorption equipment for concurrent stripping of carbon dioxide

    USGS Publications Warehouse

    Watten, B.J.; Sibrell, P.L.; Montgomery, G.A.; Tsukuda, S.M.

    2004-01-01

    The high solubility of carbon dioxide precludes significant desorption within commercial oxygen absorption equipment. This operating characteristic of the equipment limits its application in recirculating water culture systems despite its ability to significantly increase allowable fish loading rates (kg/(L min)). Carbon dioxide (DC) is typically removed by air stripping. This process requires a significant energy input for forced air movement, air heating in cold climates and water pumping. We developed a modification for a spray tower that provides for carbon dioxide desorption as well as oxygen absorption. Elimination of the air-stripping step reduces pumping costs while allowing dissolved nitrogen to drop below saturation concentrations. This latter response provides for an improvement in oxygen absorption efficiency within the spray tower. DC desorption is achieved by directing head-space gases from the spray tower (O2, N2, CO2) through a sealed packed tower scrubber receiving a 2 N NaOH solution. Carbon dioxide is selectively removed from the gas stream, by chemical reaction, forming the product Na 2CO3. Scrubber off-gas, lean with regard to carbon dioxide but still rich with oxygen, is redirected through the spray tower for further stripping of DC and absorption of oxygen. Make-up NaOH is metered into the scrubbing solution sump on an as needed basis as directed by a feedback control loop programmed to maintain a scrubbing solution pH of 11.4-11.8. The spent NaOH solution is collected, then regenerated for reuse, in a batch process that requires relatively inexpensive hydrated lime (Ca(OH)2). A by-product of the regeneration step is an alkaline filter cake, which may have use in bio-solids stabilization. Given the enhanced gas transfer rates possible with chemical reaction, the required NaOH solution flow rate through the scrubber represents a fraction of the spray tower water flow rate. Further, isolation of the water being treated from the atmosphere (1

  18. Nonequilibrium gas absorption in rotating permeable media

    NASA Astrophysics Data System (ADS)

    Baev, V. K.; Bazhaikin, A. N.

    2016-08-01

    The absorption of ammonia, sulfur dioxide, and carbon dioxide by water and aqueous solutions in rotating permeable media, a cellular porous disk, and a set of spaced-apart thin disks has been considered. The efficiency of cleaning air to remove these impurities is determined, and their anomalously high solubility (higher than equilibrium value) has been discovered. The results demonstrate the feasibility of designing cheap efficient rotor-type absorbers to clean gases of harmful impurities.

  19. Ozone and TFA impacts in North America from degradation of 2,3,3,3-Tetrafluoropropene (HFO-1234yf), a potential greenhouse gas replacement.

    PubMed

    Luecken, Deborah J; L Waterland, Robert; Papasavva, Stella; Taddonio, Kristen N; Hutzell, William T; Rugh, John P; Andersen, Stephen O

    2010-01-01

    We use a regional-scale, three-dimensional atmospheric model to evaluate U.S. air quality effects that would result from replacing HFC-134a in automobile air conditioners in the U.S. with HFO-1234yf. Although HFO-1234yf produces tropospheric ozone, the incremental amount is small, averaging less than 0.01% of total ozone formed during the simulation. We show that this production of ozone could be compensated for by a modest improvement in air conditioner efficiency. Atmospheric decomposition of HFO-1234yf produces trifluoroacetic acid (TFA), which is subject to wet and dry deposition. Deposition and concentrations of TFA are spatially variable due to HFO-1234yf's short atmospheric lifetime, with more localized peaks and less global transport when compared to HFC-134a. Over the 2.5 month simulation, deposition of TFA in the continental U.S. from mobile air conditioners averages 0.24 kg km(-2), substantially higher than previous estimates from all sources of current hydrofluorocarbons. Automobile air conditioning HFO-1234yf emissions are predicted to produce concentrations of TFA in Eastern U.S. rainfall at least double the values currently observed from all sources, natural and man-made. Our model predicts peak concentrations in rainfall of 1264 ng L(-1), a level that is 80x lower than the lowest level considered safe for the most sensitive aquatic organisms.

  20. 40 CFR 267.204 - What air emission standards apply?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 26 2010-07-01 2010-07-01 false What air emission standards apply? 267... PERMIT Tank Systems § 267.204 What air emission standards apply? You must manage all hazardous waste... incinerator, flame, boiler, process heater, condenser, and carbon absorption unit. ...

  1. 24 CFR 3280.805 - Branch circuits required.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ..., water heater, range, and central or room air conditioner, etc.). There shall be one or more circuits of... specified for ranges in § 3280.811(a)(5). For central air conditioning, see Article 440 of the National...

  2. 24 CFR 3280.805 - Branch circuits required.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ..., water heater, range, and central or room air conditioner, etc.). There shall be one or more circuits of... specified for ranges in § 3280.811(a)(5). For central air conditioning, see Article 440 of the National...

  3. 24 CFR 3280.805 - Branch circuits required.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ..., water heater, range, and central or room air conditioner, etc.). There shall be one or more circuits of... specified for ranges in § 3280.811(a)(5). For central air conditioning, see Article 440 of the National...

  4. 24 CFR 982.517 - Utility allowance schedule.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... for tenant-installed air conditioners. (3) The cost of each utility and housing service category must... services according to the following general categories: space heating; air conditioning; cooking; water... services. The PHA must provide a utility allowance for tenant-paid air-conditioning costs if the majority...

  5. 40 CFR 1066.830 - Supplemental Federal Test Procedures; overview.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... driving and a sequence of vehicle operation that accounts for the impact of the vehicle's air conditioner...) AIR POLLUTION CONTROLS VEHICLE-TESTING PROCEDURES Exhaust Emission Test Procedures for Motor Vehicles... results from the aggressive driving test element (§ 1066.831), the air conditioning test element (§ 1066...

  6. Receptacle for Optical-Fiber Scraps

    NASA Technical Reports Server (NTRS)

    Nevin, R.

    1986-01-01

    Small pieces of glass trapped by moving air. Device traps fibers in section of black air-conditioner filter material. Filter section rests on metal screen above axial fan, which pulls air down through filter. Fan is small, quiet unit of type ordinarily used to cool electronic equipment.

  7. 24 CFR 3280.709 - Installation of appliances.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... systems designed only to accept external cooling (i.e., self contained air conditioning systems, etc.) (7) The installation of a self contained air conditioner comfort cooling appliance shall meet the... fireplace or fireplace stove, air intake assembly, hearth extension and the chimney shall be installed in...

  8. Surface-plasmon mediated total absorption of light into silicon.

    PubMed

    Yoon, Jae Woong; Park, Woo Jae; Lee, Kyu Jin; Song, Seok Ho; Magnusson, Robert

    2011-10-10

    We report surface-plasmon mediated total absorption of light into a silicon substrate. For an Au grating on Si, we experimentally show that a surface-plasmon polariton (SPP) excited on the air/Au interface leads to total absorption with a rate nearly 10 times larger than the ohmic damping rate of collectively oscillating free electrons in the Au film. Rigorous numerical simulations show that the SPP resonantly enhances forward diffraction of light to multiple orders of lossy waves in the Si substrate with reflection and ohmic absorption in the Au film being negligible. The measured reflection and phase spectra reveal a quantitative relation between the peak absorbance and the associated reflection phase change, implying a resonant interference contribution to this effect. An analytic model of a dissipative quasi-bound resonator provides a general formula for the resonant absorbance-phase relation in excellent agreement with the experimental results.

  9. Experimental studies of a zeeman-tuned xenon laser differential absorption apparatus.

    PubMed

    Linford, G J

    1973-06-01

    A Zeeman-tuned cw xenon laser differential absorption device is described. The xenon laser was tuned by axial magnetic fields up to 5500 G generated by an unusually large water-cooled dc solenoid. Xenon laser lines at 3.37 micro, 3.51 micro, and 3.99 micro were tuned over ranges of 6 A, 6 A, and 11 A, respectively. To date, this apparatus has been used principally to study the details of formaldehyde absorption lines lying near the 3 .508-micro xenon laser transition. These experiments revealed that the observed absorption spectrum of formaldehyde exhibits a sufficiently unique spectral structure that the present technique may readily be used to measure relative concentrations of formaldehyde in samples of polluted air.

  10. Development of a High-Resolution Laser Absorption Spectroscopy Method with Application to the Determination of Absolute Concentration of Gaseous Elemental Mercury in Air.

    PubMed

    Srivastava, Abneesh; Hodges, Joseph T

    2018-06-05

    Isotope dilution-cold-vapor-inductively coupled plasma mass spectrometry (ID-CV-ICPMS) has become the primary standard for measurement of gaseous elemental mercury (GEM) mass concentration. However, quantitative mass spectrometry is challenging for several reasons including (1) the need for isotopic spiking with a standard reference material, (2) the requirement for bias-free passive sampling protocols, (3) the need for stable mass spectrometry interface design, and (4) the time and cost involved for gas sampling, sample processing, and instrument calibration. Here, we introduce a high-resolution laser absorption spectroscopy method that eliminates the need for sample-specific calibration standards or detailed analysis of sample treatment losses. This technique involves a tunable, single-frequency laser absorption spectrometer that measures isotopically resolved spectra of elemental mercury (Hg) spectra of 6 1 S 0 ← 6 3 P 1 intercombination transition near λ = 253.7 nm. Measured spectra are accurately modeled from first-principles using the Beer-Lambert law and Voigt line profiles combined with literature values for line positions, line shape parameters, and the spontaneous emission Einstein coefficient to obtain GEM mass concentration values. We present application of this method for the measurement of the equilibrium concentration of mercury vapor near room temperature. Three closed systems are considered: two-phase mixtures of liquid Hg and its vapor and binary two-phase mixtures of Hg-air and Hg-N 2 near atmospheric pressure. Within the experimental relative standard uncertainty, 0.9-1.5% congruent values of the equilibrium Hg vapor concentration are obtained for the Hg-only, Hg-air, Hg-N 2 systems, in confirmation with thermodynamic predictions. We also discuss detection limits and the potential of the present technique to serve as an absolute primary standard for measurements of gas-phase mercury concentration and isotopic composition.

  11. Sound absorption characteristics of aluminum foam with spherical cells

    NASA Astrophysics Data System (ADS)

    Li, Yunjie; Wang, Xinfu; Wang, Xingfu; Ren, Yuelu; Han, Fusheng; Wen, Cuie

    2011-12-01

    Aluminum foams were fabricated by an infiltration process. The foams possess spherical cells with a fixed porosity of 65% and varied pore sizes which ranged from 1.3 to 1.9 mm. The spherical cells are interconnected by small pores or pore openings on the cell walls that cause the foams show a characteristic of open cell structures. The sound absorption coefficient of the aluminum foams was measured by a standing wave tube and calculated by a transfer function method. It is shown that the sound absorption coefficient increases with an increase in the number of pore openings in the unit area or with a decrease of the diameter of the pore openings in the range of 0.3 to 0.4 mm. If backed with an air cavity, the resonant absorption peaks in the sound absorption coefficient versus frequency curves will be shifted toward lower frequencies as the cavity depth is increased. The samples with the same pore opening size but different pore size show almost the same absorption behavior, especially in the low frequency range. The present results are in good agreement with some theoretical predictions based on the acoustic impedance measurements of metal foams with circular apertures and cylindrical cavities and the principle of electroacoustic analogy.

  12. COP improvement of refrigerator/freezers, air-conditioners, and heat pumps using nonazeotropic refrigerant mixtures

    NASA Technical Reports Server (NTRS)

    Westra, Douglas G.

    1993-01-01

    With the February, 1992 announcement by President Bush to move the deadline for outlawing CFC (chloro-fluoro-carbon) refrigerants from the year 2000 to the year 1996, the refrigeration and air-conditioning industries have been accelerating their efforts to find alternative refrigerants. Many of the alternative refrigerants being evaluated require synthetic lubricants, are less efficient, and have toxicity problems. One option to developing new, alternative refrigerants is to combine existing non-CFC refrigerants to form a nonazeotropic mixture, with the concentration optimized for the given application so that system COP (Coefficient Of Performance) may be maintained or even improved. This paper will discuss the dilemma that industry is facing regarding CFC phase-out and the problems associated with CFC alternatives presently under development. A definition of nonazeotropic mixtures will be provided, and the characteristics and COP benefits of nonazeotropic refrigerant mixtures will be explained using thermodynamic principles. Limitations and disadvantages of nonazeotropic mixtures will be discussed, and example systems using such mixtures will be reviewed.

  13. Laser absorption waves in metallic capillaries

    NASA Astrophysics Data System (ADS)

    Anisimov, V. N.; Arutiunian, R. V.; Bol'Shov, L. A.; Kanevskii, M. F.; Kondrashov, V. V.

    1987-07-01

    The propagation of laser absorption waves in metallic capillaries was studied experimentally and numerically during pulsed exposure to CO2 laser radiation. The dependence of the plasma front propagation rate on the initial air pressure in the capillary is determined. In a broad range of parameters, the formation time of the optically opaque plasma layer is governed by the total laser pulse energy from the beginning of the exposure to the instant screening appears, and is weakly dependent on the pulse shape and gas pressure.

  14. Design and Development of a Nearable Wireless System to Control Indoor Air Quality and Indoor Lighting Quality.

    PubMed

    Salamone, Francesco; Belussi, Lorenzo; Danza, Ludovico; Galanos, Theodore; Ghellere, Matteo; Meroni, Italo

    2017-05-04

    The article describes the results of the project "open source smart lamp" aimed at designing and developing a smart object able to manage and control the indoor environmental quality (IEQ) of the built environment. A first version of this smart object, built following a do-it-yourself (DIY) approach using a microcontroller, an integrated temperature and relative humidity sensor, and techniques of additive manufacturing, allows the adjustment of the indoor thermal comfort quality (ICQ), by interacting directly with the air conditioner. As is well known, the IEQ is a holistic concept including indoor air quality (IAQ), indoor lighting quality (ILQ) and acoustic comfort, besides thermal comfort. The upgrade of the smart lamp bridges the gap of the first version of the device providing the possibility of interaction with the air exchange unit and lighting system in order to get an overview of the potential of a nearable device in the management of the IEQ. The upgraded version was tested in a real office equipped with mechanical ventilation and an air conditioning system. This office was occupied by four workers. The experiment is compared with a baseline scenario and the results show how the application of the nearable device effectively optimizes both IAQ and ILQ.

  15. Design and Development of a Nearable Wireless System to Control Indoor Air Quality and Indoor Lighting Quality

    PubMed Central

    Salamone, Francesco; Belussi, Lorenzo; Danza, Ludovico; Galanos, Theodore; Ghellere, Matteo; Meroni, Italo

    2017-01-01

    The article describes the results of the project “open source smart lamp” aimed at designing and developing a smart object able to manage and control the indoor environmental quality (IEQ) of the built environment. A first version of this smart object, built following a do-it-yourself (DIY) approach using a microcontroller, an integrated temperature and relative humidity sensor, and techniques of additive manufacturing, allows the adjustment of the indoor thermal comfort quality (ICQ), by interacting directly with the air conditioner. As is well known, the IEQ is a holistic concept including indoor air quality (IAQ), indoor lighting quality (ILQ) and acoustic comfort, besides thermal comfort. The upgrade of the smart lamp bridges the gap of the first version of the device providing the possibility of interaction with the air exchange unit and lighting system in order to get an overview of the potential of a nearable device in the management of the IEQ. The upgraded version was tested in a real office equipped with mechanical ventilation and an air conditioning system. This office was occupied by four workers. The experiment is compared with a baseline scenario and the results show how the application of the nearable device effectively optimizes both IAQ and ILQ. PMID:28471398

  16. Three-phase Power Flow Calculation of Low Voltage Distribution Network Considering Characteristics of Residents Load

    NASA Astrophysics Data System (ADS)

    Wang, Yaping; Lin, Shunjiang; Yang, Zhibin

    2017-05-01

    In the traditional three-phase power flow calculation of the low voltage distribution network, the load model is described as constant power. Since this model cannot reflect the characteristics of actual loads, the result of the traditional calculation is always different from the actual situation. In this paper, the load model in which dynamic load represented by air conditioners parallel with static load represented by lighting loads is used to describe characteristics of residents load, and the three-phase power flow calculation model is proposed. The power flow calculation model includes the power balance equations of three-phase (A,B,C), the current balance equations of phase 0, and the torque balancing equations of induction motors in air conditioners. And then an alternating iterative algorithm of induction motor torque balance equations with each node balance equations is proposed to solve the three-phase power flow model. This method is applied to an actual low voltage distribution network of residents load, and by the calculation of three different operating states of air conditioners, the result demonstrates the effectiveness of the proposed model and the algorithm.

  17. Self absorption of alpha and beta particles in a fiberglass filter.

    PubMed

    Luetzelschwab, J W; Storey, C; Zraly, K; Dussinger, D

    2000-10-01

    Environmental air sampling uses fiberglass filters to collect particulate matter from the air and then a gas flow detector to measure the alpha and beta activity on the filter. When counted, the filter is located close to the detector so the alpha and beta particles emerging from the filter travel toward the detector at angles ranging from zero to nearly 90 degrees to the normal to the filter surface. The particles at small angles can readily pass through the filter, but particles at large angles pass through a significant amount of filter material and can be totally absorbed. As a result, counting losses can be great. For 4 MeV alpha particles, the filter used in this experiment absorbs 43% of the alpha particles; for 7.5 MeV alphas, the absorption is 13%. The measured beta activities also can have significant counting losses. Beta particles with maximum energies of 0.2 and 2.0 MeV have absorptions of 44 and 2%, respectively.

  18. The absorption of sound by perforated linings

    NASA Astrophysics Data System (ADS)

    Hughes, I. J.; Dowling, A. P.

    1990-09-01

    This paper describes a practical application for sound-absorbent perforated screen with a bias flow through the screen. It is postulated that, if a perforated liner with a bias flow of cooling air through the liner is inserted in the afterburner section of a jet engine, all the incident sound may be absorbed at a particular frequency. Experimental results are presented on the absorptive properties of plane liners with circular apertures, showing an agreement with the theoretical model.

  19. High enthalpy arc-heated plasma flow diagnostics by tunable diode laser absorption spectroscopy

    NASA Astrophysics Data System (ADS)

    Lin, Xin; Chen, Lianzhong; Zeng, Hui; Ou, Dongbin; Dong, Yonghui

    2017-05-01

    This paper reports the laser absorption measurements of atomic oxygen in the FD04 arc-heater at China Academy of Aerospace Aerodynamics (CAAA). An atomic oxygen absorption line at 777.19 nm is utilizied for detecting the population of electronically excited oxygen atom in an air plasma flow. A scanned-wavelength direct absorption mode is used in this study. The laser is scanned in wavelength across the absorption feature at a rate of 200 Hz. Under the assumption of thermal equilibrium, time-resolved temperature measurements are obtained on one line-of-sight in the arc-heater. The good agreement of the temperature inferred from the sonic throat method suggests the equilibrium assumption is valid. These results illustrate the feasibility of the diode laser sensors for flow parameters in high enthalpy arc-heated facilities.

  20. 40 CFR 267.177 - What air emission standards apply?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 26 2010-07-01 2010-07-01 false What air emission standards apply? 267... PERMIT Use and Management of Containers § 267.177 What air emission standards apply? You must manage all... incinerator, catalytic vapor incinerator, flame, boiler, process heater, condenser, and carbon absorption unit. ...