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vol.47-1(2009/5/31)
| Introduction of completely controlled plant factory |
| A completely controlled plant factory is one of plant production systems in agriculture. Some of the advantages of the plant factory over commercial greenhouses and open field are as follows: (1) ensures fast and stable plant production under complete environmental control, (2) produces high-quality of plants, (3) allows efficient use of water and gas, and (4) fulfils agrochemical free cultivation. With regard to environmental control, spatial uniformity of light, temperature, humidity, and gas in a plant canopy is the key to produce a material bearing consistent quality. A closed system can manipulate not only the aerial conditions but also the root zone conditions. By using hydroponics, the nutrient solution condition can be controlled such that it is optimum for each growth stage. |
| Control of the Light Environment on Completely Controlled Plant Factory |
| Controlling the light environment is one of the major factor for the plant production in a completely controlled plant factory. The spectrum balance, intensity and duration of lighting are thought essentially to be important for the control of light environment. The history, the structure, the characteristic, and the use of various light sources, such as fluorescent lamp, high pressure sodium lamp, metal halide lamp, LED, etc., used at the present day are introduced in the report. The photon flux efficiency of light sources and the illumination equivalent with the photon flux are also shown in the characteristic table. |
| Control technologies for atmospheric conditions of completely controlled plant factories with artificial lamps |
| There are two types of plant factories: completely controlled and partly relying on sunlight. A plant factory of the complete control type uses artificial lamps to culture plants in a tightly closed space. The factory, which is not influenced by meteorological conditions, allows the stable production of plants of uniform quality. However, the factory, which requires air conditioning to cool heat generated by artificial lamps, is different from a plant factory partly relying on sunlight in many respects. Hence, this article focuses on the completely controlled plant factory to discuss control technologies for atmospheric environment. |
| Solution culture technique |
| In Japan the growing area in protected horticulture was highest (53,516ha) in 1998 and then decreased gradually, becoming to be 50,608 ha in 2007 according to the statistics of the Ministry of Agricultural, Forestry and Fisheries. On the contrary the solution culture area constantly increases and become to be 1,686 ha. As this area also occupied 3.3% of all the area in protected horticulture, now the solution culture or it's system is necessary for agricultural production. It is specially noted that a unitary care of cultivation and a stable production is practicable by this cultivation system because the facilities for plant production become to be large scale in recent years. Especially, this cultivation system is very important in the plant factory because plants can be cultivated safely without agricultural chemicals such as insecticides, etc. |
| Closed type transplant production system |
| Using an artificial light source, air conditioners and an automatic irrigation unit, closed type transplant production system creates a stable environment, not influenced by the external climate, and produces high-quality and seedlings under optimum temperature, CO2, light and water conditions. |
| Closed-plant-factory-system for genetically modified plants |
| In accordance with the advance of genetic engineering on plants, genetically modified plants attract a great deal of attention as the production system of pharmaceuticals, etc. For the scheduled production of these plants without being affected by climate conditions, a closed-type plant production system under controlled environments with artificial lamps is required. |
vol.47-2(2009/7/31)
| Various problems in electrostatic trouble-overview |
| For understanding of the basic electrostatics itself and some typical electrostatic problems, the elemental electrostatics theory and some basic equations are explained including the fundamental electrostatic measuring methods of the charge, the electric field and potential, and the mechanism of the electrostatic charging. The academic activity about the electrostatics is also introduced historically. The difficulty of how to prevent the electrostatic trouble is strongly related with the charging-physics and new technology causes another trouble in general. |
| Evaluation of Electrostatic Discharge Phenomenon at Manufacturing Process Basic Concept of Electrostatic Measurement and Principle of Measurement |
| As you know, IC and LCD devices are making exciting progress. According to this kind of back ground conditions, these devices are getting more sensitive about electrostatic year by year. Then IC and LCD devices will be defected often at manufacturing process and will be broken at market by electrostatic attraction (ESA) and electrostatic discharge (ESD). These days ESD solution is become one of important item for quality issue. As you know well ESD and solution which explained by Standard. A lot of customers had made EPA under standard recommendation. However, some customer still has and/or happened ESD problem at Factory or Clean Room. This problem may cause by difficulty of electrostatic voltage measurement and detect ESD event especially Charge Device Model (CDM). Therefore we have to have knowledge about appropriate method of electrostatic voltage measurement and electrostatic discharge detection. I hope that this description will serve to be a reference for your next stage of ESD solution. |
| The countermeasure technology of the static electricity troubles at production process |
| The basic processes of the static electricity countermeasure are 1st is the prevention of a static electricity occurrence, the 2nd is the promotion of the static electricity leakage and the 3rd is the neutralization by the ion. For the realization of the high countermeasure of the cost performance, understanding of a static electricity occurrence mechanism and evaluation technology is very important too. The anti-static engineering technology including the technology of the above large area is introduced. |
| Electrostatic neutralization by using an ionizer |
| A charged body forms an electric field and induces electrostatic phenomena, such as, electrostatic discharge (ESD), electrostatic induction and Coulomb's force, that cause electrostatic problems in the industry. When the charged body is conductive, the grounding is the best way to remove the electrostatic charges from the body. But, when the charged body is dielectric, the grounding is not effective to avoid the electrostatic charge accumulation, so it is necessary to improve the electric conductivity of the body. However, the improvement of the dielectric body is usually difficult, and then an ionozer is very often used to neutralize the electrostatic charges on the charged dielectric body. A corona-discharge type ionizer is most popular. Many kinds of ionizers, that is, AC type and DC type, are applied in the various industrial processes according to their ionization characteristics. At the particular conditions, a radioactive-ray ionizer, a soft X-ray ionizer, and an ultraviolet-ray ionizer are applied, too. In recent years, the international standards on the evaluation of the ionizers are established, and the quality of the ionizers is highly improved. |
| Electrostatic Countermeasure in Film Manufacturing Processes |
| In the film manufacturing processes, a large amount of electrostatic charges are often generated on films due to continuous contact and separation between the metal rolling devices and film. Electrostatic charges could give rise to serious problems such as, contamination on the films, and repelling or attraction between two pieces of films. Electrostatic discharges from the charged films can also lead to static marks on the processed film, resulting in a decrease in qualities of films, liquid crystal display (LCD), and flat panel display (FPD) products. Flammable vapors may be present during coating treatments in film product processes. Thus, electrostatic discharges have the possibility of causing fires and/or explosions. Moreover, electromagnetic noise associated with electrostatic discharges may destroy electronic circuits and cause the uncontrolled operation in various devices. Therefore, this paper introduces a fundamental knowledge and a coutermeasure against electrostatic troubles in film manufacturing process. |
| Basic knowledge and measure of an electrostatic obstacle for a semiconductor manufacturing process |
| An electrostatic is one of roots cause to damage of an electro-device as ESD. Recently, ESA topics have been focused because of its particle adsorption behavior due to Coulomb's law concerning a yield of manufacturing process directly. About electric parts, material and other industrial products which required cleanliness environment are always examine to preventive a particle adsorption caused by ESA. It is easy to understand to ESD and ESA, but it seems a difficult to coutermeasure when a principal of electrostatic behavior is not understood correctly. In this article, it is shown a basic knowledge of electrostatic issues and how to approach to coutermeasure of it with practical experiences of author. Here is said that the resistance of material and parts controlled a range of electrostatic dissipative of 106-1012Ω cm, is important for ESD preventive, and for ESA. |
| Fungi and Cultural Assets |
| Fungi in the environments around cultural assets are distributed. Even the places and materials under dry condition are contaminated with some fungi, especially osmophilic fungi. According to the case of library, art museum and histrical museum, it exactly shows the contaminated ones by mold. On the contrary, the case of national treasure of traditional materials under the wet condition was sometimes contaminated with several kinds of fungi. In this paper, we describe on the relations between the fungi and cultural assets. |
vol.47-3(2009/9/30)
| Influenza pandemic by H1N1 (swine flu) |
| April 2009, swine origin novel influenzavirus A/H1N1 suddenly emerged as pandemic strain. The outbreak began in Mexico. In early June, as the virus spread grobally, the World Health Organization (WHO) declared the outbreak to be a pandemic, but also noted that most illnesses were of moderate severity. Symptoms are similar to those of seasonal flu, and can include fever, sore throat, coughs, headache, and muscle or joint pains. But not so small number of death cases has been reported in the patients with some underlying conditions such as asthma, diabetes, obesity, heart disease, or a weakened immune system. Attack of bigger flu-wave during autumn to winter is anticipated in Japan. We have to make well organized medical service systems till then. |
| Current situation and infection control of the novel influenza A (H1N1) |
| In Mid-February, an outbreak of the respiratory disease occurred in a rural area in Mexico, and developed to the worldwide epidemic of the novel influenza. The virus was turned out to be an H1N1 subtype, which is distinct from the current strain of human A (H1N1) seasonal influenza virus and is of mainly swine origin. It descends from a triple-reassortant swine flu virus which was found in pigs in 1998, and was reported to infect several humans. The current outbreak spreaded rapidly in an unprecedented manner, resulting in the worldwide pandemic in less than six weeks. Infection control of this disease should be based on that of seasonal flu, which is mainly droplet precaution plus hand hygiene. This may also apply to community setting, where there is a limitation of the strict application of these measures. Airborne transmission is an issue both for the seasonal flu and novel influenza, without obvious evidence of its existence and with the possibility of this route. So far it is thought to be prudent to implement airborne transmission while doing aerosol-generating procedures such as endotracheal intubation and bronchoscopy. |
| Infection Control and air conditioning |
| Air conditioning is one of the most important issues in control of healthcare infections. Despite of the large impact of air conditioning, the study of this area has not been developed enough. The aim of air conditioning is to maintain the ideal environment which may suppress microorganism proliferation. In this review, the relationship between construction desing and the potential hazard of environmental pathogens are discussed. |
| Fungi in the environment and their infection |
| Fungus is a kind of Eukaryota, which consists mainly of yeast, mycelia and mushroom. Some fungi are known to cause serious infection to humans. Because of its phylogenetic similarity to human beings, antifungal drugs are generally powerless to fungi and/or toxic to humans. The most common fungal infections involving internal organs and aspesrgillosis, candidiasis and cryptococcosis, followed by zygomycosis. Most fungi produce a huge amount of spores, which are easily and abundantly found in the air of offices, residential buildings and even in hospitals. Aspergillus spp., which are the causative agents of aspergillosis, are not an exception. Inhalation of these pathogenic spores sometimes causes serious fungal infections of lungs, and then of other internal organs. In this sense, quality control of the air plays a critical role in controlling the development of fungal infections. People who are most susceptible to pulmonary fungal infections are systemically immunocompromised patients such as leukemic patients and the patients who are taking immunosuppressive agents like steroids. Those who have cavities, bronchiectasis or cysts in the lung are also susceptible. Once a fungus successfully started invading patients' lungs, treatment is often difficult due to the lack of potent antifungal agents. In fact, in invasive aspergillosis, the most common form of aspergillosis, fatality of the patients reaches almost 70-80%, and therefore prevention of these infections is critical. To this end, the importance of the indoor air quality control cannot be overemphasized. |
| Infection Control against Pandemic Flu -Part.1 Disinfecting Method Indoors |
| Pandemic flu is now a big concern in the world. Air cleaning systems with chlorine dioxide (ClO2) gas which is effective against influenza virus A have been developed. The experiments were conducted to discuss the effects of environmental factors on ClO2 gas concentration indoors. Ten environmental conditions were examined. It was showed that high humidity and lighting had great impacts on ClO2 gas reduction. The other factors did not affect on ClO2 gas concentration in this experiment. The ClO2 gas concentration was simulated using CFD method. A field survey was carried out in the building equipped with the ClO2 gas diffusion system to evaluate the perceived air quality of occupants. Same level of subjective perceived air quality was observed under the condition with ClO2 gas diffusion, compared with the condition without it. |
| Countermeasures against novel influenza, part2―An approach from architectural hygiene technologies |
| In April, 2009, the novel influenza A (H1N1) which is caused by a new flu virus was first detected. In Japan, the outbreaks caused by novel influenza A (H1N1) have been reported in May and the increasing number of cases is being reported internationally. About the measure of influenza, the approaches from various fields are required. This report is described focusing on the countermeasure of the infection route in prevention of spread of influenza from the view point of architectural hygiene technologies. |
| Estimation of Microbe Take-off from Coil Fin for HVAC System |
| The purpose of this study is to estimate the influence of microbes adhering to the surface of a coil fin for HVAC system upon the airborne microbe concentration in a room. We have predicted the number of microbes taking-off from the wet fin polluted by microbes, using a microbial mass transfer model on the wet fin surface and the experimentally obtained coefficients for the model. When the fungi (i.e. Aspergillus niger, Penicilium oxalicum or Cladosporium cladosporioides) are observed in the condensed water from a coil fin more than 109 CFU/m3, the fungal concentration of the downstream air of the coil fin will be more than tens CFU/m3. Therefore it will be the pollutant source which can't be ignored in reference to the environmental standard (AIJES-A002-005) for interior airborne fungal concentration (50 CFU/m3). We have also found that the possibility of take-off of a microbe from a wet coil fin is closely related to the hydrophobic property of the microbe surface. Because most of the fungi that are commonly observed in the indoor environment have the hydrophobic surfaces of less than about 45mJ/m2 in surface tension, it is likely that they take-off from the wet fin surface by the airflow without depending on splash of the condensed water from the fin surface. |
| A Review of Chinese Standards for Air Filters |
| A review was given for the history and current situation of Chinese Standards for air filters. Major filter companies adopted European standards as CRAA standards based on particle counting techniques. The national standard group stayed with old methods temporarily. A schematic comparison for different classification systems was given. |
| Air Filter (1) Middle Efficiency Air Filter (Pleated and Pocket Style) |
| The middle efficiency air filters have been very broadly used in various applications. So this paper describes about the history, definitions, test methods, structures, media, applications and recent trends. The one trend is ecological developments of the air filter, such as reduce, reuse, recycle and lower CO2 emission. And the others is the international standardization (ISO) and JIS standardization by fractional particle efficiency of air filters. |
vol.47-4(2009/11/30)
| Particulate respirator |
| Specifications of particulate respirators in Japan were stipulated in 1950 by the Ministry of Labour notifications. Certification regarding the types of particulate respirators has since been conducted according to these notifications and the certified particulate respirators have the marks indicating the type certification on the face piece and on the filtering material. There have been several amendments with regard to the specifications for the type certification of particulate respirators. The currently valid specifications are these amended in 2000. Generally used particulate respirators are divided into two major categories; the replaceable type particulate respirators and the disposable type particulate respirators. The replaceable type falls into either front-or-back-mounted type particulate respirators or direct-coupled type particulate respirators. This classification is based on the differences in the usage of the respirators. Further, particulate respirators are divided into 12 categories according to filtering performance with regard to test particles, particulate collection efficiency, inlet valves, outlet valves and other elements. It should be noted that the different modes of the usage of particulate respirators are defined according to the ministerial notifications for different kinds of particulates, different job characteristics and different performance levels of respirators. |
| Gas Mask |
| Gas mask is the most convenient and portable type of respirator which removes atmospheric contamination with toxic gases and vapors. The history of gas mask of the type we recognize as gas masks at present started in the World War I which was developed for the protection of soldiers' respiration against chemical weapons. This origin tells the role and requirements of gas masks well. The small canisters and cartridges are required to remove a certain kind or a certain group of gases and vapors completely from the atmospheric air for a certain period when the air is drawn through the packed can by the lung of the wearer with a tolerable breathing resistance. The current greatest needs of gas masks are brought about by industrial workers for the protection of their respiration against miscellaneous kinds of gases and vapors. For these uses, the Government issued the standard of gas mask and the rules of the certification system to provide reliable gas masks to the users. The Technology Institution of Indistrial Safety is the organization registered by the Ministry of Health, Labor and Welfare performing the national approval tests for gas masks. This article reviews the outline of the standard, certification system and the practical procedure for the manufacturers of gas masks to apply to the certification test and to obtain the certificate to the types of gas mask products. |
| Powered air purifying respirator (PAPR) |
| Powered Air Purifying Respirator (PAPR) is air-purifying respirator consisting mainly of battery-operated blower, filter, battery and facepiece such as tight-fitting facepiece, hood or faceshield. PAPR holds a mechanism where purified air, passed through filter(s) and/or cartridge(s), is supplied to the facepiece. As the pressure inside the facepiece is maintained positive due to the supply of air, air leakage, which occasionally takes place with a creation of a slight opening between face and facepiece, is prevented; and thus, PAPR is known for its high protection performance compared to particulate respirators or gas masks. PAPR is now drawing attention as effective personal protective equipment, compared to particulate respirator, as represented by latest revisions of regulation, enforced by the Ministry of Health, Labor and Welfare of Japan, where the use of PAPR became mandatory in works involving tunnel construction and asbestos removal and of JIS Standard, JIS T 8157:2009, "Powered Air Purifying Respirator." PAPR market has been growing rapidly by introduction of breath-response PAPR, an innovative concept where air volume synchronized with breathing pattern is supplied to wearer. In this article, outline and summary of JIS T 8157:2009, including the comparison with the standards currently enforced in the US and Europe, are described. In addition, authors introduce a brief overview of latest PAPR with multifunction and of an advanced respirator evaluation system. |
| Atmosphere-Supplying Respirator |
| The outline of atmosphere-supplying respirators is explained. Atmosphere-supplying respirators are mainly classified into air-supplied respirators and self-contained breathing respirators. The features of those types in each group are introduced. Expression of the protection performance of respirators are introduced, and the usage of protection factors are explained. |
| Basic study of bactericidal effect by using microplasma |
| Bactericidal effect is experimentally investigated by using micro plasma. Microplasma is one of the atmospheric pressure non-thermal plasma. It is a dielectric barrier discharge which has high intensity electric field at relatively low discharge voltages around 1 kV due to the very small discharge gap. Microplasma expected to practical application for bactericidal effect, since its discharge voltage is low, and its power system would be relatively compact. In this study, Gram-negative Escherichia coli HB101 and Gram-positive Bacillus subtilis JCB 20036 were the target to be sterilized. From the series of experiments, decrease in the amount of germs was effectively obtained after microplasma treatment. The effect of bactericidal effect increased as the discharge voltage increases. When E. coli was used as target, bactericidal effect rate by air-plasma was 100% at a discharge voltage of 1.05 kV and by nitrogen-plasma was 77% at 1.15kV. These results could be the combined effect of active radical species, ozone, UV radiation, and high electrical fields of microplasma. |
| The Contamination Control in Printed-wiring-board Manufacturing |
| Printed wiring boards serve wirings for the electronic circuits assemblies at each step. Their size as an industry approximately account for one fourth of the total semiconductor industries. The figure has remained unchanged for the past few decades. The line-and-spaces of their advanced products had long been running around 100 times those of advanced semiconductors. Recently, however, the rates of miniaturization of printed wiring boards have not fully caught up with the paces at which the design-rules for semiconductors are getting finer. Manufacturing yields of printed wiring boards have stayed about 90%. "Contamination control" comes in the first place as the issues to be tackled. Needless to say, the entire manufacturing process needs to be clean. But the installation of a sophisticated clean-room alone does not solve the problem. Broad, field-oriented, sometimes plain and simple approaches often play more important roles. This paper gives overviews on the characteristics of the manufacturing process of printed wiring boards in the light of cleanliness and clean technologies applied on the process. |
| Air Filter (2) HEPA Filter |
| High Efficiency Particulate Air Filters, commonly known as "HEPA Filters" were originally developed to confine airborne radioactive particles in exhaust ventilation systems employed during the United States' Manhattan Project, but are now widely used in various applications. In this paper, some examples of these various applications are introduced, as well as the historical defnitions and characteristics of HEPA filters. |
vol.47-5(2010/1/31)
| Introduction of industrial spray nozzles and their characterization methods |
| The primary reason for the breaking-up liquid into droplets is the advantage gained by resulting increase in the specific surface area of liquid. Spray nozzles are used for various processes as a representative device to atomize liquid or make air or liquid jet by passing it through a small orifice at a given upstream pressure. In this paper, "industrial sprays" are defined that they should be used in a process that has a tangible end product, following the book entitled "Industrial Spray and Atomization-Design, Analysis and Applications". The fundamental properties of industrial spray nozzles and their characterization methods are described and outlined. |
| Air purification technology using electrostatic atomization |
| A device to cool a discharge electrode to cause condensation of water vapor in surrounding air, and then electrostatically atomize the condensed water by applying high voltage to the discharge electrode has been developed. The electrostatically-atomized water mist created through electrostatic atomization by this device has been confirmed to have a diameter of approximately 20nm. In addition, simultaneous formation of radicals was verified by ESR (Electron Spin Resonance) analysis. It has been confirmed that this electrostatically-atomized water has the effects of deodorization by adsorbing odors and deactivation of pollen or mite antigens. An air cleaner equipped with this electrostatic atomization device has been developed. |
| Removal of Gaseous Contaminant by air washer using splay nozzle |
| Air washers are widely equipped in recent semiconductor manufacturing factories to remove undesirable gaseous matters such as NH3, SOx from outdoor air. Recently, the appropriate choice of spray nozzles and mist eliminator for the air washer has enabled them to be more sophisticated than the conventional ones that have a large body and a high ratio of liquid to gas (L/G). In addition, the air washer equipped with the heat recovery system was successfully developed as a new application. The new air washer system including the heat recovery type washer is described in this paper. |
| Removal of Fine Particles from Solid Surfaces by an Impinging Air Jet |
| Outline of the removal of single solid particles adhered to a solid surface using a high-speed impinging air jet is introduced with particular attention to the effect of operating conditions on the removal efficiency. The operating conditions introduced are the air pressure in the air jet nozzle, the distance between the nozzle tip and the surface and the scanning speed of the target flat plate. In addition, the removal by a pulsed air jet and high frequency vibrating jet are also introduced. Effect of the operating conditions described here on the removal efficiency could be correlated by indexes based on the fluid dynamics, i.e. the removal efficiencies obtained under various air pressures and the distances between the nozzle tip and the surface could be correlated by the dynamic pressure of the air jet calculated by assuming a free jet. The high efficiency removal area around the jet impinging point was found to be almost the same as the imaginary impinging area of the free jet onto the surface. The removal efficiencies under constant air pressure in the nozzle decreased with increase in the scanning speed of the target plate. The effect of the scanning speed on the removal efficiency can be converted to the effect of jet duration time. |
| Chemical-free cleaning process, steam and water mixed spray |
| As feature size shrinking of semiconductor devices, new cleaning methods are required in order to attain good device yield and reliability. Here we introduce a new surface cleaning method which cleans the surface without chemicals. Relatively low pressure steam is mixed with purified water at upstream zone of nozzle body and sprayed to the target wafer. Using this new method, we are able to not only strip photo-resist very quickly, but also clean the wafer surface, i.e., eliminate nanometer-scale particles. In this report, we present the device configuration, spray characteristics and examples of cleaning. Finally, we discuss the mechanism of this cleaning method. |
| Energy saving humidification method for cleanrooms using one-fluid atomizing nozzles |
| This paper discusses how to solve the problems associated with the humidity control system using atomized water to save energy in cleanrooms for manufacturing electronic devices. The major problems are accurate control of sprayed water quantity and evaporating speed of ultrapure water in sprayed mist. We have solved these problems experimentally and theoretically as described in this paper, and therefore the system can be installed in any plant, new or existing. Our estimation indicates that energy for air-conditioning can be reduced over 10% a year if this system is installed in an existing plant. |
| Application of the spray technology to heat mitigation |
| Evaporative latent heat of water is large compared with the other liquid. Therefore it is possible to lower the air temperature if there is a means to vaporize water easily in the air without using much energy. The dry-mist system consists of high pressure pump (6MPa) which is used for pressurizing water and atomizing mist, plumbing, various kinds of valves and mist nozzles. This system can artificially create natural phenomenon of transpiration by trees. And under the condition that relative humidity is 70%, the dry mist can shift the environment condition from "hot" to "a little hot" where the majority does not feel uncomfortable. The dry-mist was introduced into "Expo 2005 Aichi JAPAN" for the first time, and its effect was demonstrated. Recently the development of the DRY-MIST system for a residence which consumes less energy is in progress and its purpose is to shift the target from large area such as station or shop to small area such as the porch of dwelling. That's because its system consumens 1/7 of energy of the room air-conditioner. |
| Technical report for New Standard ISO15900 |
| A new international standard ISO15900 "Determination of particle size distribution--Differential electrical mobility analysis for aerosol particles" was published in May 2009. The development of this international standard was achieved as a result of collaborative work by participants of ISO/TC24/SC4/WG12 from several countries around world including Japan. ISO15900 defines terms, explains the principal of electrical mobility analysis for aerosol particles, recommends the value of particle properties and equations, provides methods of periodic testing and calibration of equipment, and explains uncertainties of measurements. This report is the practical guide for ISO15900 standardization activities, and the introduction of technical information and bibliography all round. |
| Electrostatic Precipitator |
| In this course, electrostatic precipitator for abut a typical office building, overview of its structure, definition of performance explain and apply applications. The example of electrostatic precipitator, maintenance, to explain further how to handle after use. |
vol.47-6(2010/3/31)
| Mechanism of Olfaction in the Brain |
| Olfaction is the very important sense in our daily lives. We have not known the mechanism of olfaction how its sensing information is accepted and transacted until now. However, there was the biggest event of Novel Prize on the "Discovery in the Mechanism of Olfaction" by Dr. Buck & Dr. Axel, in 2004. Recently, "Odor Map" in the olfactory bulb was found by Dr. Mori and et al. In the other hand, no one knows the olfactory higher-information center in the human brain. Therefore, we have been trying to study the olfactory information processing on the perception and cognition in the human brain using the various non-invasive measuring methods, such as EEG, MEG, fMRI and PET. In the near future, the role of olfaction will be found on the memory and emotion. |
| Psychophysiological evaluation of the effect of odor on brain function |
| The effects of odors on brain function can be evaluated by electroencephalography (EEG). Two methods of EEG analysis are recommended for this purpose :1) power spectrum analysis of EEG background activity. Scalp distribution of alpha waves is an index of extent of synchronization of brain activity. 2) Event-related potential (ERP) is an electrophysiological representation of processing of sensory inputs of the brain. Among ERP components, P300 is most suitable for the evaluation of influence of odor. The combination of these methods is thought to be a good candidate to noninvasively clarify the change of brain function by odors from different aspects. |
| Perception of Smell |
| Characteristics of odor threshold, perceived intensity, odor quality including odor classification and odor identification, and odor hedonics were mentioned as basic aspects in perception of smell. Then, individual differences were shown experimentally in each aspect and the factors of the individual differences were discussed by points of view in physical factor like decline of olfactory performance by age or disease, and high sensitivity by female hormone, a factors of experience or learning to specific odor, cognitive factor as a preconceived notion, and hereditary factor. |
| Quality control and estimation of uncertainty in olfactometry |
| Measurement of odor is a crucial element of odor management, regulation and control. Odor regulation based on the measurement of an "odor index," a sensory index of odor measured using the triangular odor bag method, was introduced in the Offensive Odor Control Law in 1995 in Japan. Problems relating to the interpretation of measurement results, however, have been reported by the person concerned. To solve these problems, the estimation of uncertainty in odor measurement would seem to be useful. In this paper, the procedure and the quality control framework of the triangular odor bag method are explained and the feasibility of estimation of uncertainty in olfactometry is discussed. |
| Instrumental Analysis and Sensory Evaluation with Analytical Instruments for Knowing about Total Characters of Odor |
| Odor has the function to propagate the information on odor materials to human beings. It needs to measure both material's side and sensory side for knowing about total characters of odor. Results from instrumental analysis of odor just reveal composition of volatiles. On the other hand, odor is evaluated by the sensory expression that we share. Therefore, it is important how to relate both data with greatly different character for odor researchers. The present paper is a review of the relevant literature for the odor analysis method combined with instrumental analysis and sensory evaluation method. |
| Measurement of odor (GC sniff and Electronic nose) |
| It is better to clarify which aspect of odor we should recognize before analyzing the odor. To measure the odor, there are two phases. One of them is to analyze the odor compounds, and another is to know how the man senses. It is very important that there are two sides about how the man recognize the odor. That is, the output signals of odor receptor and the final recognition of odor in the brain. As a consequence, there are three aspects of odor, which means that the odor compound, the output signal of receptor and the reorganization of brain. |
| A simplified sample preparation technique for the analysis of off-flavor using MonoTrap and TD-GC-MS-Olfactometory |
| In the analysis of some off-flavors which vaporize from product, information obtained from olfactory is important to determine compounds that provide bad smell. GC/Olfactometory is one of the efficient techniques to determine the key compound from mixture of volatile compounds, and the setting, at the end of column the effluent is split into two or more lines: one part is directed to the human nose and the other part to instrumental detector such as FID or MSD, etc. As improvement of performance is remarkable in recent years, combining with GC/O, MSD plays an important part in identification of the compound by spectral data. This essay consists of introduction of GC/O, and analysis example for claim management by GC/MS/-O method that uses prepared samples by MMSE which is brand-new technique for extraction of volatile compounds. |
| Evaluation of the Odor Emitted from Foods and Electronic Products |
| Performance of analytical instruments makes rapid progress recently. Therefore, there is GC-MS-Olfactometer which is combined sensitivity of human olfaction and analysis equipment. The study using GC-MS-Olfactometer is introduced in this paper. |
| Machinery Air Filter (Automatic Rewinding Type, Automatic Regeneration Type, Automatic Self-cleaning Viscous Type) |
| Air filters have long been used for removal of dust particles from outdoor air to be taken into buildings. This report describes the examples of various applications, structure, example of installation, maintenance methods, disposal after use, and expectative trend, etc. of filtration media type machinery air filters. |
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Air Cleaning Association