White Fluorescent Lamps Research Articles

照度レベルと光源の演色性の違いによる物体色の明るさ感

It has been reported in a number of investigations that the subjective brightness of object colors is affected by changing the color rendering properties of lighting sources. However, the paucity of reports on various illuminance levels promoted us to investigate it. The subjective experiment was done for 15 test color chips under various illuminance levels covering 1280 to 1 lx. We used reference standard type cool white fluorescent lamp and six kinds test fluorescent lamps.The results show that the subjective brightness of object colors in the photopic range is effected by the increase of light saturation on the color chips by changing the type of fluorescent tubes. it did not show any change in the mesopic range.

Influences of ultra‐violet (UV)‐blue light radiation on the growth of cotton. II. Photosynthesis, leaf anatomy, and iron reduction

Abstract Cotton (Gossypium hirsutum L.) plants grown under low pressure sodium lamps (LPS) developed chlorosis which was similar in appearance to iron‐stress induced chlorosis, while plants under cool white fluorescent lamps (CWF) at the same level of photosynthetically active radiation (PAR) developed normally. These illumination sources differ in spectral irradiance; CWF lamps emit ultra violet (UV), whereas LPS lamps do not. Ultraviolet radiation is capable of reducing Fe3+ to Fe2+ through a chlorotic leaf which may be important in establishing an active iron fraction in the leaf. Root reduction of Fe3+ to Fe2+ was lacking in Fe‐stressed cotton under LPS light, but was present under CWF light. Net photosynthesis, photosynthetic electron transport, and leaf chlorophyll content were lower under LPS than CWF light in most of the growing media studies (soil or solutions with nitrate‐ or ammonium‐nitrogen supplied). Chloroplast ultrastructure and leaf thickness were also altered by LPS irradiance. Electron ...

Effects of FLONLIZER, ultraviolet sterilizer, on Legionella species inhabiting cooling tower water.

Legionella pneumophila in sterile distilled water was not detected after ultraviolet irradiation by FLONLIZER, a new-type sterilizer, at a flow rate of 82.5 to 364.8 liters/hr. When irradiated by FLONLIZER at a flow rate of under 324.0 liters/hr, no viable cells of legionellae, other heterotrophic bacteria and bacterivorous protozoa were detected in the cooling tower water, which was found to contain L. pneumophila. No viable cells of L. pneumophila and L. bozemanii suspended in sterile distilled water were detected after the irradiation with UV-doses of over 6.16 X 10(3) micro W.sec/cm2. At the irradiation of low UV-doses under 1.06 X 10(4) micro W.sec/cm2, the viable count of legionellae recuperated by photoreactivation from UV-damage increased with the exposure time under a white fluorescent lamp. However, in the samples irradiated with UV-doses of over 3.52 X 10(4) micro W.sec/cm2, equal to the FLONLIZER, legionellae did not recuperate even after 18 hr illumination with a white fluorescent lamp. FLONLIZER is thus expected to act as a sterilizer which can control the legionellae inhabiting cooling tower systems placed in outdoor space.

The effect of supplemental irradiation with different light sources on growth and flowering of gloxinia ( Sinningia speciosa (Lodd.) Hiern)

The relative efficiency of a warm white fluorescent lamp, a high-pressure metal halide lamp, a high-pressure sodium lamp and a low-pressure sodium lamp on growth and flowering of three cultivars of Sinningia speciosa (‘Burgdorf’, ‘Gerda Lodder’, ‘Peace’) has been studied under winter conditions at latitude 60°N. The light sources were compared at three irradiance levels (10, 14 and 18 W m −2 in the wavelength range 400–1000 nm). The growth rate and growth habit were markedly affected by both light source and irradiance level, and specific cultivar reactions were recorded. The differences recorded between light sources in rate of development, dry weight production, plant diameter and adventitious shoot formation were in general more pronounced at lower than at higher irradiance levels.

Attraction of Some Adult Midges (Diptera: Chironomidae) of Florida to Artificial Light in the Field

The attraction of pestiferous species of adult Chironomidae to commercially available lamps of various colors and wattages was studied by employing New Jersey light traps along the shoreline of a central Florida lake. Glyptotendipes paripes Edwards, Goeldichironomus holoprasinus Goeldi, Chironomus crassicaudatus Malloch, and species of Tanypodinae were predominant in the collections. A comparison of 100-W incandescent lamps showed that white was preferred over yellow, and both were preferred over red, orange, green or blue. Analysis of deviance indicated that these differences were due primarily to differences in intensity (lux), although smaller effects of color and differences in response among species were detected. No differences were observed in preference between 60-W white incandescent or fluorescent lamps. These results were consistent with previous laboratory studies, and indicate that manipulating light intensity, rather than color, may be more appropriate in the overall development of an integrated control strategy of nuisance chironomid midges.

In search of an improved method for assessing the colour rendering properties of light sources

The original experimental work of CIE to establish a method for assessing the colour rendering properties of light sources has been analysed. The spectral power distribution of the Standard Warm White fluorescent lamp, used in that experiment to define a General Colour Rendering Index (Ra) equal to 50, is presented with extended spectral range and resolution. This lamp was used to compute new Ra indices when the CIE(1964)UVW formula was substituted by the CIELUV or the new, improved SVF colour space formula. Ten fluorescent and discharge lamps and two extra sets of colour samples were included in this investigation. The Special Colour Rendering Indices (Ri) for each sample of a set of 24 saturated colours show large deviations when the UVW formula is substituted by the SVF formula. Less variation is seen for the averaged Ra indices. However, for the Warm White de Luxe lamp investigated by the CIE committee, only the SVF formula yields a Ra index equal to that obtained by visual rating. The SVF formula includes a correction for chromatic adaptation that correlates well with physiological data. This improved adaptation transform makes it possible to use daylight illumination as a fixed reference source. This leads to drastic changes of the Ra-values, mainly due to a systematic degradation of Ra with decreasing correlated colour temperature. It is suggested that the use of the SVF formula, in combination with a set of 20 colour samples of constant lightness and saturation and with hues evenly distributed along the colour circle, will lead to an improved colour rendering index, tentatively called the Rb index. Our investigations indicate that, compared to the present CIE Ra index, only minor changes will result for the Standard, de Luxe and broad-band type of lamps. For modern energy saving lamps with irregular spectral power distribution, however, like three-three-band and most of the discharge lamps, the Rb index may deviate significantly and lead to more realistic values.

Effects of supplementary light to mother plants on adventitious shoot formation in flower peduncle segments of Begonia × hiemalis Fotsch in vitro

Plants of two Begonia × hiemalis cultivars (‘Schwabenland’ and ‘Nixe’) were grown in a greenhouse and continuously illuminated (24 h a day) from late October to early March, with light from warm white fluorescent lamps (L“WW”), high pressure mercury lamps (HPI/T) or high pressure sodium lamps (SON/T), each at three irradiance levels (5, 10 or 15 W m −2). The control received light continuously (0.8 W m −2) from incandescent lamps (INC). Every third week, plant material (flower peduncles) was collected for in vitro culture. The adventitious shoot formation was strongly dependent on cultivar, length of mother plant illumination and light source. The use of L“WW”, HPI/T or SON/T improved the regeneration ability of flower peduncle segments compared to control. Prolonged irradiation lowered the regeneration in ‘Schwabenland’, especially when HPI/T lamps were used.

点滴時における輸液中アスコルビン酸の安定性におよぼす通気管有無の影響

The effects of intravenous drip infusions with or without aerotube on the stability of ascorbic acid (AsA) were studied by determination of AsA and partial pressure of oxygen. AsA and sodium riboflavin phosphate, which promotes the photo-oxidation of AsA, were added to 14 kinds of commercial infusion solutions in consideration of practical conditions in hospital. When exposed to white fluorescent lamp (2000 lux, 3 hr), residual ratios of AsA in usual infusion solutions were 40-60% with aerotube and 11-49% without aerotube. Residual ratios of AsA (2000 lux, 6 hr) in total parenteral nutrition solutions, to which 13 kinds of vitamins and trace elements (Fe, Cu, Zn, Mn) had been added, were about 90% with aerotube and about 70% without aerotube. Partial pressure of oxygen dissolved in the solution without aerotube was increased by the bubbling of air during drip administration. Therefore, the oxidizing degradation of AsA in infusion solution without aerotube was promoted when compared with the solution with aerotube.

CONFIGURATIONAL PHOTOISOMERIZATION OF BILIRUBIN IN VITRO—I. QUENCHING OF Z→E ISOMERIZATION BY TWO‐WAVELENGTH IRRADIATION

Abstract A simple rate‐equation theory of configurational photoisomerization of bilirubin (BR) is presented and used to discuss the Z→E photoisomerization of BR in HSA solutions irradiated with laser light in the blue‐green spectral region. The analytical expression of Z, E‐BR:HSA (PBR) concentration at photoequilibrium (PE) is used to derive the PBR concentration from the spectrophotometric data on absorbance difference spectra. The PBR values are in good agreement with those recently reported in the case of 10 nm‐bandwidth filtered light. Both sets of data give a best‐fit value of the BR, PBR quantum yield ratio equal to 2.3 in the case of BR:HSA ratio equal to 1:2.Successive irradiation of BR/HSA solutions with different wavelengths (457/488/457 nm) provides further support for the reversibility of the photoreaction. However, differences between the intermediate PE values have been found, and may reveal departures from the simple Z,Z→Z,E isomerization in BR/HSA solutions.The possibility of controlling the formation of Z, E‐BR/HSA has been demonstrated using simultaneous irradiation with blue (457 nm) and green (514 nm) laser beams. The two‐wavelength scheme takes advantage of the reversibility of the BRIPBR reaction, and of the differences between BR/PBR absorption spectra and quantum yields. Efficient quenching of PE PBR is achieved when green substantially exceeds (10–40 times) blue light intensity. This experiment may simulate what actually occurs during clinical phototherapy with white and green fluorescent lamps, where the quenching of PBR at the formation sites may prevent diffusion of this slowly excreted isomer and, at the same time, increase the formation of the more rapidly excretable structural, non‐reversible isomers, such as lumirubin.

BILIRUBIN PHOTOISOMERIZATION UNDER GREEN LIGHT

Recent clinical studies have shown that green fluorescent light is more effective in reducing serum bilirubin (BR) than is broad-spectrum white fluorescent light. During phototherapy BR is converted to more polar isomeric structures which are excreted principally in the bile. The most rapidly formed photoproducts are configurational isomers, principally Z,E-BR, which accumulate in the serum and are slowly excreted with first-order kinetics. The other major photoproduct is a structural isomer of BR called lumirubin (LR) which is formed more slowly but excreted more rapidly than the configurational isomers. The relative contribution of these two photochemical reactions to the efficacy of phototherapy is not known. In this study, we measured the steady-state serum concentrations of these two classes of photoproducts in premature infants treated with either green or white fluorescent lamps. The concentration of Z,E-BR in the serum of infants treated with green light was significantly less than in infants exposed to white light. In contrast, the concentration of LR was greater in the serum of infants treated with green light. These data suggest the clinical efficacy of green phototherapy may be the result of increased production (and elimination) of lumirubin.

Physiological and ultrastructural changes in the chloroplasts of snap bean plants under LPS lamps during chlorosis and regreening

Abstract Iron chlorosis‐like symptoms developed in the terminal leaves of susceptible bean (Phaseolus vulgaris L. ‘Astro') plants when grown in growth chambers containing low pressure sodium (LPS) lamps that are deficient in UV and blue wavelengths. Plants grown under broad‐band radiation, provided by cool white fluorescent lamps, did not develop chlorosis. Ultrastructural and metabolic investigations examined the progress of chlorosis in leaves of plants exposed to nutrient end radiation stress under LPS lamps. Addition of full‐strength Hoagland's #1 nutrient solution or Peter's* 20–20–20 fertilizer to plants grown under LPS lamps resulted in the degradation of maturing chloroplasts in the terminal leaves. After the starch reserves were depleted, the internal membrane system degenerated. Well‐formed grana, characteristic of normal chloroplasts, were degraded, giving rise to spherical membrane structures. Chlorophyll and protein were lost and granular accumulations formed in the chloroplasts. This paper d...

Influence of spectral quality on the growth response of intact bean plants to brassinosteroid, a growth‐promoting steroidal lactone. II. Chlorophyll content and partitioning of assimilate

The chlorophyll content and partitioning of assimilate of bean (Phaseolus vulgaris L. ‘Pinto′) plants were determined 6 days after treatment of the second internode (I2 with 5 μg of brassinosteroid (BR), a growth‐promoting steroidal lactone. Plants were grown for 6 days under equal levels (90 μmol s‐1 m‐2) of photosynthetic photon flux density (PPFD) provided by cool white fluorescent (CWF) or incandescent (INC) lamps and equal levels of far‐red (28 W m‐2, 700–800 nm) radiation provided by the same INC or far‐red (FR) fluorescent lamps. Brassinosteroid treatment had no appreciable effect on total biomass production but caused a decrease of 15–20% dry matter distribution in the upper portion of the shoot, a small (4%) but constant increase in dry matter in l2 and a large (11–16%) increase in dry matter in the lower portion of the shoot (especially I1). Treatment with BR increased assimilate accumulation in the primary leaves, especially under INC and FR lamps, and reduced dry matter in the trifoliate leaves. BR also caused a 16–21% reduction in total leaf area and even a greater reduction in area of the trifoliate leaves, but significantly increased specific leaf weight of the primary leaves and the first trifoliate leaf and the amount of dry matter in the lateral shoots under all radiation sources. In comparison to controls, BR treatment increased dry matter accumulation in the treated internode 3.3x under CWF and 1.6x under INC or FR. BR treatment also increased chlorophyll content in the primary leaves under all radiation sources and in the trifoliate leaves under CWF and INC lamps. These findings suggest a possible mobilization role of BR and establish the importance of adequate PPFD (and photosynthate) for maximum swelling and splitting response to brassinosteroid.

Influence of spectral quality on the growth response of intact bean plants to brassinosteroid, a growth‐promoting steroidal lactone. I. Stem elongation and morphogenesis

The growth response of bean (Phaseolus vulgaris L. ‘Pinto′) plants treated with 5 μg of brassinosteroid (BR) in the bean second‐internode assay was measured in a controlled environment under 3 radiation sources: cool white fluorescent (CWF), far‐red (FR) fluorescent and incandescent (INC) lamps. Growth comparisons were made under equal levels (90 μmol s‐1 m‐2) of photosynthetic photon flux density provided by CWF or INC lamps and equal levels of far‐red (28 W m‐2, 700–800 nm) radiation provided by the same INC or FR lamps. Treatment of the second internode with BR produced a sequential increase in elongation, curvature, and swelling under normal bioassay conditions (CWF lamps), as observed previously with brassins. In addition, BR induced marked splitting of the treated internode provided that ample photosynthate was available. Spectral quality had a differential effect on internodal elongation. Under CWF lamps, internodes, 6 days after BR‐treatment, were 2–3 times longer than those of controls; under INC or FR lamps they were 30–60% shorter than those of controls. In all cases, BR‐treatment greatly stimulated accumulation of photosynthate in the treated internode, as indicated by fresh and dry weights and stem diameter measurements. This suggests a possible mobilization role for BR in the intact plant. Brassinosteroid also partially overcame the natural inhibitory effects of CWF radiation on stem elongation.

Axenic tissue culture and callus formation of the marine brown alga Laminaria angustata.

A method for axenic tissue culture and callus formation of the marine brown alga Laminaria angustata were established for the first time. Axenic medullary tissues were obtained from the stipes of the sporoplytes by the punching method using cork borer. Callus tissues have been induced from the medullary tissues on ASP 12-NTA medium solidified with 1.0% agar. These cultures were maintained in an incubator at 14°C and illuminated with cool white fluorescent lamps at ca. 2000 1x with 14 hr light and 10 hr dark cycle. This method for tissue culture will contribute to advances in breeding and cultivation of Laminaria plants.

Postharvest Effects of Dark Storage, Light Duration, and Source on Keeping Quality of Ficus benjamina L.1

Abstract Ficus benjamina was stored in the dark for 0, 3, 6, 9, or 12 days and then held in a simulated interior environment (SIE) for 12 weeks under 6, 12, or 24 hours/day light duration of either incandescent (INC) or Cool White fluorescent (CWF) lamps at 20 μE m−2s−1 photosynthetically active radiation (PAR). Leaf drop was less and plant grade was higher with shorter dark storage periods. Plants lighted for 24 hours/day had less leaf drop and better plant grade than those lighted for shorter durations. Chlorophyll content was greater as light duration increased for plants held under CWF lamps. Plants lighted for 6 hr/day under INC lamps had the lowest chlorophyll content after 12 weeks in the SIE.

Postharvest Effects of Various Light Sources and Duration on Keeping Quality of Ficus benjamina L.1

Abstract Ficus benjamina was held in light-and-temperature-controlled chambers for 12 weeks under 3 light sources of 20 μE m−2s−1 incandescent (INC) lamps, 20 μE m−2s−1 Cool White fluorescent (CWF) lamps, or 10 μE m−2s−1 INC + 10 μE m−2s−1 CWF light combination totaling 20 μE m−2s−1 photosynthetically active radiation (PAR). Plants also received 4 light durations (6, 12, 18, or 24 hr/day). Growth index was greater for plants held under INC. When plants were held under the light combination, leaf drop was reduced and plant grade was improved. Dry weight and plant grade increased and leaf drop decreased when plants were lighted for 24 hr/day. Chlorophyll content decreased under the light sources in the following order: CWF> light combination >INC.

Influence of Intensity and Duration of Cool White Fluorescent Lighting and Fertilizer on Growth and Quality of Foliage Plants1

Abstract Brassaia actinophylla Endl., Chamaedorea elegans Mart., Dieffenbachia maculata (Lodd.) G. Don ‘Exotica’, Dracaena marginata Lam., and Ficus benjamina L. were grown for 1 year under 13 or 26 μE m−2sec−1 from Cool White fluorescent lamps for 12, 18, or 24 hours daily durations. Increasing light duration to 24 hours daily decreased quality of all plants tested, with Brassaia, Chamaedorea, and Dieffenbachia being most affected. The primary symptoms resulting from constant light were foliar chlorosis and decrease in plant quality, although necrotic spotting appeared at times. By experiment termination, best plants overall were associated with 26 μE m−2sec−1 light for 12 or 18 hours duration and poorest with 26 μE m−2sec−1 light and 24 hours duration. A second factorial experiment with Dieffenbachia and Dracaena tested effects of 3 fertilizer levels (0, 0.67, or 1.30 g Osmocote/3 months per 15-cm pot) under 2 light intensities (13 or 26 μE m−2sec−1) and 2 light durations (12 or 24 hours) on plant quality. Higher fertilizer levels had a limited effect on plant quality, while influence of light intensity and duration was similar to the initial experiment.

Postharvest Effects of Ancymidol on Ficus benjamina L.1

Abstract Ficus benjamina were treated with ancymidol [α-cyclopropyl-α- (p- methoxyphenyl)-5-pyrimidine methanol] as a soil drench using 1.0 mg/15-cm pot plus 200 ppm spray. Plants were exposed to dark storage treatments (0, 4, 8, and 12 days) in shipping boxes before being held 4 months in a simulated interior environment (SIE) under 15 μE m−2s−1 photosynthetically active radiation (PAR) from incandescent (INC) lamps or Cool White fluorescent (CWF) lamps. Leaf drop was less for ancymidol-treated plants for all dark storage periods in comparison to untreated plants. In addition, leaf drop was less on plants held in SIE 4 months under INC lamps. Ancymidol-treated plants had better plant grade for all dark storge periods than untreated plants when held under both lamp sources and were superior under INC lamps.

アマノリ属Ｐｏｒｐｈｙｒａ培養用人工光源の検討

To determine of suitable artificial light source for laver culture, 4 types of arc lamp, e. g. white fluorescent lamp, high pressure mercury lamp, thallium mercury lamp and metal-halide lamp were examined. According to the resuls of culture test of germlings or laver thallus in a vessel equipped the test lamp, the most suitable lamp was selected with the respect to the growth rate, thallus color and contamination by the other algae under the same light intensity. The results were as follows. (1) In the culutre illuminated with the thallium mercury lamp laver thallus showed high gorwth rate, dark greenish color and contaminants did not occur, in consequence thallium mercury lamp was the most suitable one for laver culutre. (2) In the cluture illuminated with the fluorescent lamp, high pressure mercury lamp and metal-hiald lamp laver thallus showed reddish black in color and much contaminants occurred. (3) Metal-halide lamp was considered to have an advantage of the highest energy effciency.

Photochemical reduction of iron. I. light reactions

Abstract The role of spectral quality in the photochemical reduction of Fe3+ in vitro was investigated under various lamps to determine the basis for severe chlorosis observed in certain species and cultivars under low pressure sodium (LPS) lamps when used as a sole source of artificial light in plant growth chambers. The comparative efficacy of LPS and cool white fluorescent (CWF) lamps was evaluated by means of an automated spectroradiometer with capability of measuring spectral irradiance every nanometer from 250 nm to 840 nm; by visible appearance of the plants (e.g., extent of greening and morphological development); by physiological measurements (e.g., of biomass and chlorophyll content); and by use of ferrozine as a chemical actinometer. Reduction of Fe3+ to Fe2+, measured as Fe2+ ferrozine (at 562 nm) was more than 4 times as great under CWF lamps, which emit appreciable amounts of UV and blue irradiance, as under LPS lamps, which are deficient in these wavelengths. By use of appropriate filters to selectively remove the UV or UV + blue wavelengths from CWF lamps or other light sources, it was possible to greatly reduce or prevent the in vitro photoreduction of ferrous iron. Conversely, the addition of CWF lamps to a LPS growth room greatly enchanced Fe3+ photoreduction in solution. Citrate was found to be required for the in vitro photoreduction of 59FeC13 solutions. Further studies are needed, however, to relate photochemical and biochemical changes in the intact plant in order to determine the precise role of UV and blue radiation in the photochemical reduction of Fe3+ in vivo.