503 Evidence for Toxic Effects of Cellulose Acetate in UV Exclusion Studies on `Ashley' Cucumber Seedlings

Cellulose diacetate has been widely used in UV-B enhancement studies under field and controlled-environment conditions since the early 1970s to remove wavelengths below ≈290 nm, without any evidence of toxicity effects. However, while conducting UV-B exclusion studies in window boxes covered with cellulose diacetate (CA) or in Plexiglas chambers lined with CA, there was marginal chlorosis and cotyledon epinasty in `Ashley' cucumber, which is normally resistant to elevated UV-B, while seedlings exposed to open sunlight and those grown under polyester (PE) film to exclude UV-B were free of visible injury. These findings suggested that the CA filter itself may be causing toxicity. To test this hypothesis, a UV exclusion study was conducted in which CA or Teflon (T), both UV-B and UV-A transmitting films, were used to cover window boxes in the following four combinations (top/bottom): CA/CA, CA/T,T/CA, and T/T. When CA was used as the bottom filter (CA/CA and T/CA), the plants showed significantly greater leaf injury and a 2- to 3-fold reduction in growth than when T was used as the bottom filter (CA/T and T/T). These findings suggest that toxicity is caused by CA itself rather than by solar UV-B radiation, possibly as a result of outgassing of phthalates known to be used as plasticizers in the manufacture of CA. Further evidence that CA was responsible for leaf injury was provided by a companion study in which T was replaced by PE and damage was still observed, although no significant growth effects of CA position were observed.

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OZONE AND SULPHUR DIOXIDE INTERACTION IN WHITE BEAN AND SOYBEAN

Canadian Journal of Plant Science ◽

10.4141/cjps77-175 ◽

1977 ◽

Vol 57 (4) ◽

pp. 1193-1198 ◽

Cited By ~ 21

Author(s):

G. HOFSTRA ◽

D. P. ORMROD

Keyword(s):

Sulphur Dioxide ◽

Controlled Environment ◽

Plant Weight ◽

Leaf Injury ◽

Mature Leaves ◽

Bean Plants ◽

White Bean ◽

Glycine Max L ◽

Soybean Leaves ◽

Weight Data

White bean (Phaseolus vulgaris L.) and soybean (Glycine max L. Merr.) plants were exposed to 15 pphm (v/v) ozone and/or 7.5, 15, 30, 45 or 60 pphm sulphur dioxide for 5 or 10 days in controlled environment facilities. Ozone-induced leaf injury consisted of bronze flecking on mature leaves of both species. Sulphur dioxide caused bifacial necrotic lesions on mature leaves of some white bean plants exposed to 60 pphm and had no effect on soybean leaves. The combined gases on white bean resulted in leaf injury symptoms consisting of yellow interveinal chlorosis which appeared several days later than did bronzing on corresponding leaves exposed to ozone alone. In soybean, characteristic ozone-induced lesions appeared on leaves of plants exposed to the combined gases but the onset of injury was several days later than in plants exposed only to ozone. Both injury ratings and plant weight data corresponded to the observed injury pattern.

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Response of Non–Dicamba-Resistant Soybean to Dicamba As Influenced by Growth Stage and Herbicide Rate

Weed Technology ◽

10.1017/wet.2018.64 ◽

2018 ◽

Vol 32 (5) ◽

pp. 513-519 ◽

Cited By ~ 6

Author(s):

Spencer McCown ◽

Tom Barber ◽

Jason K. Norsworthy

Keyword(s):

Seed Yield ◽

Weed Management ◽

Yield Loss ◽

Soybean Seed ◽

Growth Stages ◽

Target Movement ◽

Visible Injury ◽

Leaf Injury ◽

Resistant Varieties ◽

Wide Range

AbstractIntroduction of the Roundup Ready® Xtend system (Monsanto Co., St. Louis, MO) provides an alternative weed management option for growers, but of concern is the risk of dicamba injury to sensitive crops, particularly soybean from off-target movement and tank contamination. Experiments were conducted to determine the response of soybean to low rates of dicamba over a wide range of application timings. Two glufosinate-resistant varieties (HBK 4950LL–indeterminate and HALO 5.45LL–determinate) commonly grown in Arkansas were chosen for these studies. Two rates of dicamba, 2.18 and 8.75 g ae ha–1(1/256× and 1/64× of the POST labeled rate for dicamba-resistant soybean), were applied at two vegetative (V4, V6) and six reproductive (R1 to R6) growth stages. Compared to the nontreated control, dicamba applied during late vegetative and early reproductive growth of soybean caused leaf injury, plant height reduction, and seed yield loss for both soybean cultivars. Averaged across dicamba rates applied at R1, soybean seed yield was reduced 14% for the HBK 4950LL cultivar and 19% for the HALO 5.45LL cultivar. Averaged over rates, dicamba applied at R1 to the HALO 5.45LL and HBK 4950LL soybean resulted in 48% and 43% visible injury 4 wk after treatment, respectively. Grain yield was similar to that of the nontreated control when dicamba was applied at the later reproductive stages averaged across rates.

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Similarities in the biochemical changes between solar UV exclusion and GA application in Amaranthus caudatus

Physiology and Molecular Biology of Plants ◽

10.1007/s12298-009-0041-7 ◽

2009 ◽

Vol 15 (4) ◽

pp. 367-370 ◽

Cited By ~ 5

Author(s):

Anand Sharma ◽

K. N. Guruprasad

Keyword(s):

Biochemical Changes ◽

Amaranthus Caudatus ◽

Solar Uv ◽

Uv Exclusion

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Influence of Ambient UV-A and UV-B on Growth, Chlorosis, and Flavonoid Content of Cucumber

HortScience ◽

10.21273/hortsci.30.4.898c ◽

1995 ◽

Vol 30 (4) ◽

pp. 898C-898

Author(s):

Donald T. Krizek ◽

Roman M. Mirecki ◽

Steven J. Britz

Keyword(s):

Uv Radiation ◽

Root Biomass ◽

Floral Development ◽

Differential Sensitivity ◽

Flavonoid Content ◽

Total Leaf Area ◽

Solar Uv ◽

Extreme Sensitivity ◽

Stem Leaf ◽

Uv Exclusion

The influence of ambient UV radiation on growth, chlorosis, and flavonoid content was examined in four cultivars of cucumber (`Ashley', `Poinsett', `Marketmore', and `Salad Bush'). Plants were grown from seed in UV exclusion chambers consisting of UV transmitting plexiglass (10% T, 285 nm), lined with 3- or 5-mil Llumar (10% T, 399 or 404 nm) to exclude UV-A and UV-B, 5-mil polyester (10%T, 319 nm) to exclude UVB, or cellulose acetate (10% T, 291 nm) to transmit UV-A and UV-B. Plants were grown in 15 cm plastic pots containing vermiculite and were fertilized daily with nutrient solution. Despite their differential sensitivity to supplemental UV-B radiation, all four cultivars responded similarly to the exclusion treatments. After 19 to 21 days, plants grown under ambient UV-A and UV-B generally had less stem, leaf, and root biomass and less total height and total leaf area than those grown under conditions in which UV-A and UV-B or only UV-B was excluded. Flavonoid content, leaf number, and floral development were unaffected by UV. These findings demonstrate the extreme sensitivity of cucumber to current levels of solar UV radiation.

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Sintesis dan Karakterisasi Selulosa Asetat dari A-Selulosa Fiber Cake Kelapa Sawit

Jurnal Pendidikan dan Teknologi Indonesia ◽

10.52436/1.jpti.86 ◽

2021 ◽

Vol 1 (9) ◽

pp. 357-364

Author(s):

Indarianti Utami ◽

Abu Hasan ◽

Robert Junaidi

Keyword(s):

Cellulose Acetate ◽

Palm Oil ◽

Cellulose Fiber ◽

Product Yield ◽

Cellulose Content ◽

Cellulose Diacetate ◽

Acetyl Content ◽

High Product Yield ◽

Solid Form

Penelitian tentang sintesis dan karakterisasi selulosa asetat dari ?-selulosa fiber cake kelapa sawit ini telah dilakukan dengan menggunakan anhidrida asetat sebagai acetylating agent. Penelitian ini bertujuan untuk mendapatkan selulosa asetat dengan klasifikasi selulosa diasetat yang memiliki yield produk yang tinggi, mempelajari pengaruh variasi rasio selulosa:anhidrida asetat, waktu asetilasi, dan suhu asetilasi untuk mendapatkan selulosa asetat dengan kondisi yang optimal dari ?-selulosa fiber cake kelapa sawit. Penelitian ini menggunakan variasi rasio selulosa:anhidrida asetat (1:5; 1:10; 1:15), waktu asetilasi (0,5; 1; 1,5; 2; 2,5)jam, dan suhu asetilasi (25 dan 40) oC menghasilkan 30 sampel produk. Hasil penelitian menunjukkan bahwa selulosa asetat yang didapatkan berupa selulosa diasetat dengan bentuk padatan berupa serbuk, berwarna putih gading, dan tidak berbau serta memiliki kadar ?-selulosa sebesar 84,29 % dengan kadar air 9,16 % pada rasio selulosa:anhidrida asetat (1:10), waktu asetilasi 1,5 jam, dan suhu asetilasi 40oC dengan nilai yield produk, kadar asetil, dan derajat substitusi berturut-turut 49 %, 39,97 %, dan 2,5. Research on the synthesis and characterization of cellulose acetate from palm oil ?-cellulose fiber cake has been carried out using acetic anhydride as an acetylating agent. This study aims to obtain cellulose acetate with cellulose diacetate classification which has a high product yield, study the effect of variations in the ratio of cellulose:acetic anhydride, acetylation time, and acetylation temperature to obtain cellulose acetate with optimal conditions from palm oil ?-cellulose fiber cake. This study used variations in the ratio of cellulose:acetic anhydride (1:5; 1:10; 1:15), acetylation time (0.5; 1; 1.5; 2; 2.5) hours, and acetylation temperature (25 and 40) oC produces 30 product samples. The results showed that the cellulose acetate obtained was in the form of cellulose diacetate with a solid form in the form of powder, ivory white, and odorless and had 84.29% of a-cellulose content with 9.16% of a moisture content at the ratio of cellulose:acetic anhydride (1 :10), acetylation time 1.5 hours, and acetylation temperature 40oC with product yield, acetyl content, and degree of substitution 84.6%, 39.97%, and 2.5, respectively.

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Synthesis and characterization of cellulose acetate naphthoate with good ultraviolet and chemical resistance

e-Polymers ◽

10.1515/epoly-2016-0293 ◽

2017 ◽

Vol 17 (4) ◽

pp. 333-340 ◽

Cited By ~ 2

Author(s):

Jun Song ◽

Mei Liu ◽

Zhanping Yang ◽

Songwei Xu ◽

Bowen Cheng ◽

...

Keyword(s):

Cellulose Acetate ◽

Chemical Structure ◽

Chemical Resistance ◽

Molar Ratio ◽

Synthesis And Characterization ◽

Cellulose Diacetate ◽

H Nmr ◽

Ultraviolet Resistance ◽

Acid Catalyzed

AbstractCommercial cellulose diacetate with a degree of substitution (DS) of 2.45 was partly deacetylated to cellulose acetate (CA) with different DSs by acid-catalyzed hydrolysis and then reacted with 1-naphthoyl chloride (NpCl) to synthesize CA naphthoate (CANp). Fourier transform infrared and 1H-NMR were used to characterize the chemical structure of CANp. The DS of naphthoate moiety (DSCANp) could be varied from 0.18 to 0.98 by adjusting the molar ratio of –OH in CA unit to NpCl, the DS of CA (DSCA), and the reaction time and temperature. When DSCA was 2.01 and the molar ratio was 1:6, the maximum DSCANp of the product was achieved after a reaction at 80°C for 2 h. With the increase of DSCANp, the thermal stability decreased slightly whereas the anti-ultraviolet property was enhanced. Moreover, the obtained films containing CANp exhibited good ultraviolet resistance as well as chemical resistance.

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Effects of solar UV radiation on birch and pine seedlings in the sub-Arctic

Polar Record ◽

10.1017/s0032247400017769 ◽

2002 ◽

Vol 38 (206) ◽

pp. 233-240 ◽

Cited By ~ 5

Author(s):

M. Turunen ◽

M.-L. Sutinen ◽

K. Derome ◽

Y. Norokorpi ◽

K. Lakkala

Keyword(s):

Uv Radiation ◽

Dry Weight ◽

Growing Season ◽

Control Treatment ◽

Daily Maximum ◽

Solar Uv Radiation ◽

Growing Seasons ◽

Acrylic Plate ◽

Solar Uv ◽

Uv Exclusion

AbstractThe responses of Betula pubescens Ehr. (European white birch), B. pendula Roth (silver birch) and two provenances of Pinus sylvestris L. (Scots pine) to solar ultraviolet (UV < 400 nm) radiation were investigated in a UV-exclusion field experiment during the 1997–99 growing seasons in Finnish Lapland (68°N). The seedlings were grown from seed under UV-B exclusion (a clear polyester filter) and UV-B/UV-A exclusion (a clear acrylic plate) as compared to control treatment (a polyethene filter) and ambient plants (no plastic filter). The mean daily maximum solar biologically effective UV-B irradiance (UV-BE) was 88 mW m-2, 68 mW m-2, and 91 mW m-2 for 1997, 1998, and 1999. A number of growth and biomass variables, PSII (Photosystem II) efficiency, and total concentration of nitrogen were recorded during and/or at the end of the experiment. Exposure (191 d) to solar UV radiation over three growing seasons did not cause many statistically significant UV effects in the growth or biomass of the seedlings. The only significant impacts of UV exclusion were found in P. sylvestris provenance Enontekiö. During the first growing season, the UVB/ UV-A exclusion treatment significantly accelerated the height increment (18–20%) off. sylvestris, and in the same seedlings, the UV-B exclusion treatment resulted in significantly increased dry weight of one-year-old needles (45–57%) after the second growing season. These UV impacts could not be seen at the end of the experiment or in any other species. The low concentration of N in current foliage was related to increased dry weight, but not to solar UV radiation (control vs UV exclusion). The present study indicated that solar UV radiation had limited, but sometimes transient, impacts on the growth of tree seedlings in the sub-Arctic. Longer-term field studies are needed, however, in order to detect the cumulative characteristics of the UV responses.

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Cellulose Acetate Lamination: A Literature Review and Survey of Paper-Based Collections in the United States

Restaurator International Journal for the Preservation of Library and Archival Material ◽

10.1515/res-2015-0015 ◽

2015 ◽

Vol 36 (4) ◽

Author(s):

Molly McGath ◽

Sonja Jordan-Mowery ◽

Mark Pollei ◽

Steven Heslip ◽

John Baty

Keyword(s):

United States ◽

Literature Review ◽

Cellulose Acetate ◽

Stable Condition ◽

Cost Benefit ◽

The United States ◽

Present Condition ◽

Cellulose Diacetate ◽

The Cost ◽

Physical And Chemical

AbstractCellulose acetate (CA) lamination, a technique to strengthen documents by sealing them between sheets of thermoplastic film, was widespread from the 1930s to the 1990s. Its use gradually stopped in the 1980s amid concerns about the physical and chemical instability of the laminate and the degradation risks posed to the treated document. Despite concerns about CA lamination, no coordinated effort has taken place to establish the various materials and techniques used in cellulose acetate laminations or to determine the number and present condition of CA laminated documents in US collections. In this paper, we review the chemistry and methods used in CA lamination. We then report results of a survey of 52 US institutions with significant laminated collections. We find that at least 2.9 million laminated documents exist in US collections, and most of those documents are observed to be in stable condition. A majority of the institutions used cellulose diacetate (CDA) as the laminating film and as few as 0.6% CDA laminated documents have been delaminated. The results should aid institutions in determining the cost benefit in the management of these significant collections.

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