Search

Arctic Ocean surface circulation change should not be viewed as the strength of the anticyclonic Beaufort Gyre. While the Beaufort Gyre is a dominant feature of average Arctic Ocean surface circulation, empirical orthogonal function analysis of dynamic height (1950–89) and satellite altimetry–derived dynamic ocean topography (2004–19) show the primary pattern of variability in its cyclonic mode is dominated by a depression of the sea surface and cyclonic surface circulation on the Russian side of the Arctic Ocean. Changes in surface circulation after Arctic Oscillation (AO) maxima in 1989 and 2007–08 and after an AO minimum in 2010 indicate the cyclonic mode is forced by the AO with a lag of about 1 year. Associated with a one standard deviation increase in the average AO starting in the early 1990s, Arctic Ocean surface circulation underwent a cyclonic shift evidenced by increased spatial-average vorticity. Under increased AO, the cyclonic mode complex also includes increased export of sea ice and near-surface freshwater, a changed path of Eurasian runoff, a freshened Beaufort Sea, and weakened cold halocline layer that insulates sea ice from Atlantic water heat, an impact compounded by increased Atlantic Water inflow and cyclonic circulation at depth. The cyclonic mode’s connection with the AO is important because the AO is a major global scale climate index predicted to increase with global warming. Given the present bias in concentration of in situ measurements in the Beaufort Gyre and Transpolar Drift, a coordinated effort should be made to better observe the cyclonic mode. more...

Unprecedented quantities of heat are entering the Pacific sector of the Arctic Ocean through Bering Strait, particularly during summer months. Though some heat is lost to the atmosphere during autumn cooling, a significant fraction of the incoming warm, salty water subducts (dives beneath) below a cooler fresher layer of near-surface water, subsequently extending hundreds of kilometers into the Beaufort Gyre. Upward turbulent mixing of these sub-surface pockets of heat is likely accelerating sea ice melt in the region. This Pacific-origin water brings both heat and unique biogeochemical properties, contributing to a changing Arctic ecosystem. However, our ability to understand or forecast the role of this incoming water mass has been hampered by lack of understanding of the physical processes controlling subduction and evolution of this this warm water. Crucially, the processes seen here occur at small horizontal scales not resolved by regional forecast models or climate simulations; new parameterizations must be developed that accurately represent the physics. Here we present novel high resolution observations showing the detailed process of subduction and initial evolution of warm Pacific-origin water in the southern Beaufort Gyre., Warming ocean water plays a significant role in accelerating Arctic sea ice melt. Here the authors present detailed observations of warm water of Pacific origin entering and diving beneath the Arctic ocean surface, and explore the dynamical processes governing its evolution. more...

As part of the 2013 and 2014 North Pole Environmental Observatories (NPEO) in the Amundsen Basin of the Arctic Ocean, two similar temperature microstructure experiments were performed with different results. In 2013, vertical fluxes were through a thermohaline staircase, and in 2014 the thermohaline staircase was largely absent. Here we investigate the reasons for this difference. The 2013 data set was characterized by an extensive thermohaline staircase, indicative of the diffusive convective type of double diffusion (DC), from 120-250 m depths. The staircase was absent above 200 m in 2014, even though analysis of density ratio, Rρ, still shows high susceptibility to DDC. In the depth range of interest, survey averaged Rρ = 3.8 in 2013 and Rρ = 3.6 in 2014, indicating that the temperature-salinity structure in the pycnocline was not the cause of the lack of a staircase in 2014. We propose that exceptionally weak turbulent mixing, even for the typically quiescent Arctic Ocean, allowed formation of the staircase in 2013. Average thermal diffusivity, KT, between 50 – 120 m is elevated in 2014, 2 x 10−5 m2s−1, compared to 2013, 1 x 10−6 m2s−1. However, vertical Atlantic Water (AW) DC heat fluxes in 2013 are remarkably consistent with turbulent heat fluxes in 2014. Similar data sets collected in 2007 and 2008 both resemble 2014, showing consistently higher mixing values compared to 2013. The suppression of turbulence during NPEO 2013 resulted from increased near-surface stratification, possibly caused by a different large-scale circulation pattern that year. more...

The low levels of mechanically driven mixing in many regions of the Arctic Ocean make double diffusive convection virtually the only mechanism for moving heat up from the core of Atlantic Water towards the surface. In an attempt to quantify double diffusive heat fluxes in the Arctic Ocean, a temperature microstructure experiment was performed as a part of the North Pole Environmental Observatory (NPEO) 2013 field season from the drifting ice station Barneo located in the Amundsen Basin near the Lomonosov Ridge (89.58N, 758W). A diffusive convective thermohaline staircase was present between 150 and 250 m in nearly all of the profiles. Typical vertical heat fluxes across the high-gradient interfaces were consistently small, O(1021 )Wm22 . Our experiment was designed to resolve the staircase and differed from earlier Arctic studies that utilized inadequate instrumentation or sampling. Our measured fluxes from temperature microstructure agree well with the laboratory derived flux laws compared to previous studies, which could find agreement only to within a factor of two to four. Correlations between measured and parameterized heat fluxes are slightly higher when using the more recent Flanagan et al. [2013] laboratory derivation than the more commonly used derivation presented in Kelley [1990]. Nusselt versus Rayleigh number scaling reveals the convective exponent, g, to be closer to 0.29 as predicted by recent numerical simulations of single-component convection rather than the canonical 1/3 assumed for double diffusion. However, the exponent appears to be sensitive to how convective layer height is defined. publishedVersion more...

[1] Observational studies have shown that an unprecedented warm anomaly has recently affected the temperature of the Atlantic Water (AW) layer lying at intermediate depth in the Arctic Ocean. Using observations from four profiling moorings, deployed in the interior of the Canada Basin between 2003 and 2011, the upward diffusive vertical heat flux from this layer is quantified. Vertical diffusivity is first estimated from a fine-scale parameterization method based on CTD and velocity profiles. Resulting diffusive vertical heat fluxes from the AW are in the range 0.1–0.2 W m−2 on average. Although large over the period considered, the variations of the AW temperature maximum yields small variations for the temperature gradient and thus the vertical diffusive heat flux. In most areas, variations in upward diffusive vertical heat flux from the AW have only a limited effect on temperature variations of the overlying layer. However, the presence of eddies might be an effective mechanism to enhance vertical heat transfer, although the small number of eddies sampled by the moorings suggest that this mechanism remains limited and intermittent in space and time. Finally, our results suggest that computing diffusive vertical heat flux with a constant vertical diffusivity of ∼2 × 10−6 m2 s−1 provides a reasonable estimate of the upward diffusive heat transfer from the AW layer, although this approximation breaks down in the presence of eddies. more...

[1] To determine whether deep background mixing has increased with the diminishment of the Arctic sea ice, we compare recent internal wave energy and mixing observations with historical measurements. Since 2007, the North Pole Environmental Observatory has launched expendable current probes (XCPs) as a part of annual airborne hydrographic surveys in the central Arctic Ocean. Mixing in the upper 500 m is estimated from XCP shear variance and Conductivity-Temperature-Depth (CTD) derived Brunt-Vaisala frequency. Internal wave energy levels vary by an order of magnitude between surveys, although all surveys are less energetic and show more vertical modes than typical midlatitude Garrett-Munk (GM) model spectra. Survey-averaged mixing estimates also vary by an order of magnitude among recent surveys. Comparisons between modern and historical data, reanalyzed in identical fashion, reveal no trend evident over the 30 year period in spite of drastic diminution of the sea ice. Turbulent heat fluxes are consistent with recent double-diffusive estimates. Both mixing and internal wave energy in the Beaufort Sea are lower when compared to both the central and eastern Arctic Ocean, and expanding the analysis to mooring data from the Beaufort Sea reveals little change in that area compared to historical results from Arctic Internal Wave Experiment. We hypothesize that internal wave energy remains lowest in the Beaufort Sea in spite of dramatic declines in sea ice there, because increased stratification amplifies the negative effect of boundary layer dissipation on internal wave energy. more...

Streamflow information is critical for addressing any number of hydrologic problems. Often, streamflow information is needed at locations that are ungauged and, therefore, have no observations on which to base water management decisions. Furthermore, there has been increasing need for daily streamflow time series to manage rivers for both human and ecological functions. To facilitate negotiation between human and ecological demands for water, this paper presents the first publicly available, map-based, regional software tool to estimate historical, unregulated, daily streamflow time series (streamflow not affected by human alteration such as dams or water withdrawals) at any user-selected ungauged river location. The map interface allows users to locate and click on a river location, which then links to a spreadsheet-based program that computes estimates of daily streamflow for the river location selected. For a demonstration region in the northeast United States, daily streamflow was, in general, shown to be reliably estimated by the software tool. Estimating the highest and lowest streamflows that occurred in the demonstration region over the period from 1960 through 2004 also was accomplished but with more difficulty and limitations. The software tool provides a general framework that can be applied to other regions for which daily streamflow estimates are needed. more...

Source: Geophysical Research Letters, doi: 10.1002/2016GL070252 Due to severe nutrient and light limitation, the central Arctic Ocean has been characterized as a region of low primary productivity, with high retention of carbon in the surface waters. Using an in-depth analysis of published and new measurements of turbulent microstructure and high-resolution profiles of nitrate concentration, we reassess the vertical supply of nitrate to the Polar Mixed Layer and the associated export of particulate organic matter across the nitracline. We estimate annual export production to be approximately 1.5–3 g C m−2, but regional differences in both current and future potential of export production are large, with the eastern Arctic being least constrained by vertical nutrient supply and the western Arctic the most. Future changes in export production are assessed using a 1-D budget model; increases in the Atlantic sector are possibly compensated by decreases in the rest of the central Arctic Ocean such that the net change might be insignificant. more...

Losing its character The eastern Eurasian Basin of the Arctic Ocean is on the far side of the North Pole from the Atlantic, but it is becoming more like its larger neighbor as the climate warms. Polyakov et al. show that this region is also evolving toward a state of weakened stratification with increased vertical mixing, release of oceanic heat, and less sea ice. These changes could have considerable impacts on other geophysical and biogeochemical aspects of the Arctic Ocean system and presage a fundamentally new Arctic climate state. Science , this issue p. 285 more...

Streamflow information is critical for solving any number of hydrologic problems. Often times, streamflow information is needed at locations which are ungauged and, therefore, have no observations on which to base water management decisions. Furthermore, there has been increasing need for daily streamflow time series to manage rivers for both human and ecological functions. To facilitate negotiation between human and ecological demands for water, this paper presents the first publically-available, map-based, regional software tool to interactively estimate daily streamflow time series at any user-selected ungauged river location. The map interface allows users to locate and click on a river location, which then returns estimates of daily streamflow for the location selected. For the demonstration region in the northeast United States, daily streamflow was shown to be reliably estimated by the software tool, with efficiency values computed from observed and estimated streamflows ranging from 0.69 to 0.92. The software tool provides a general framework that can be applied to other regions for which daily streamflow estimates are needed. more...

StreamStats (http://streamstats.usgs.gov) is a U.S. Geological Survey (USGS) Web-based geographic information systems application developed as a tool for water-resources planning and management, engineering design, and numerous other applications, and is a useful tool for analyzing Total Maximum Daily Loads (TMDLs). StreamStats users can select data-collection station locations shown on an interactive map interface to obtain previously published streamflow statistics, basin characteristics, and descriptive information for the stations. Users also can select any location along a stream to obtain the drainage-basin boundary, basin and climatic characteristics, and streamflow statistics for the location, estimated based on either regional regression equations or on the flow per unit drainage area for the statistics at nearby streamgaging stations. These estimates of streamflow statistics can be useful for TMDL analysis. For example, StreamStats applications for several states provide estimates of 7-day, 10-year low flows, which are used by many states for permitting of effluent discharges. more...

StreamStats is a U.S. Geological Survey Web-based geographic information systems application developed as a tool for water-resources planning and management, engineering design, and other applications. The primary functionality of StreamStats allows users to obtain drainage-basin boundaries, basin characteristics, and streamflow statistics for gaged and ungaged sites. Recently, tools that allow stream-network navigation were added to StreamStats. These tools allow users to select any point along a stream and locate activities upstream and downstream from the selected point, such as streamgaging stations, dams, and point-source discharges, and obtain information about such activities. Users also can obtain stream-reach addresses and estimates of streamflow statistics for the selected points. more...

StreamStats is a U.S. Geological Survey Web-based GIS application developed as a tool for water resources planning and management, engineering design, and other applications. StreamStats' primary functionality allows users to obtain drainage-basin boundaries, basin characteristics, and streamflow statistics for gaged and ungaged sites. Recently, Web services have been developed that provide the capability to remote users and applications to access comprehensive GIS tools that are available in StreamStats, including delineating drainage-basin boundaries, computing basin characteristics, estimating streamflow statistics for user-selected locations, and determining point features that coincide with a National Hydrography Dataset (NHD) reach address. For the state of Kentucky, a web service also has been developed that provides users the ability to estimate daily time series of drainage-basin average values of daily precipitation and temperature. The use of web services allows the user to take full advantage of the datasets and processes behind the StreamStats application without having to develop and maintain them. more...

A method for measuring the deuterium-hydrogen-exchange accessibility of cellulose and of chemically modified cellu luloses, based on the use of D218O and mass spectroscopy, has been applied to a variety of well characterized samples. The expected correlation of the values obtained with moisture regain determined at 65% relative humidity and 21° was found for unsubstituted celluloses, but not for substituted celluloses having covalently attached oxymethylene groups. It is postulated that this lack of correlation for the substituted celluloses is due to association of water with the oxymethylene groups, thus leading to higher moisture regain values than predicted from the deuterium-hydrogen-exchange values. A good correlation, however, was found between the deuterium accessibility of these substituted samples and their alkali centrifuge values. The effect on deuterium accessibility of heating purified cotton cellulose with D218O in sealed capillary tubes was also investigated. more...

A significant portion of the nonheme iron and acid-labile sulfide of axenically grown Entamoeba histolytica was obtained in a colored, low molecular weight protein fraction from centrifuged amoeba homogenates following gel filtration. The colored component was further purified by adsorption on and elution from DEAE-cellulose. Preparations so purified had 390 280 absorbance ratios as great as 0.87. The oxidized form had absorbance peaks at 390, 315, and 280 nm; the enzymatically reduced form, at 350 nm. The difference spectra showed a major peak at 420 nm, and a minor one at 310 nm. The substance was converted to apoprotein and reconstituted with iron and H2S by methods developed for clostridial ferredoxin. When chromatographed on a Sephadex G-50 column calibrated with spinach and clostridial ferredoxins its molecular weight appeared to be about 6000, i.e., close to that of the clostridial protein. The substance is considered to be amoebal ferredoxin, but there remains some uncertainty concerning the number of atoms of iron and acid-labile sulfide per molecule. Its physiological role in the organism is not yet understood. more...

Bromine-containing derivatives of phosphonitrilic chloride were investigated as pos sible durable flame retardants for cotton fabrics. These, including brominated allyl phosphonitrilate, 2, 3-dibromopropyl phosphonitrilate, and the bromoform adduct polymer of allyl phosphonitrilate, were applied to cotton fabrics as polymeric products from or ganic solvent or from aqueous emulsions. Evaluation tests on tear strength and the durability of the flame resistance to laundering were made. more...

Samples of partially carboxymethlyated cotton print cloth were cross-linked by treat ment with vapors from a mixture containing hydrochloric acid and paraformaldehyde. Selected properties of these samples were compared with those of samples given the cross-linking treatment first and the carboxymethylation treatment last. It was found that samples cross-linked by this vapor treatment had low values for water of imbibition and that partially carboxymethylated samples had high values. When the samples were cross-linked by the vapor treatment and then carboxymethylated, values for water of imbibition approached those of samples carboxymethylated only. When the cross-linking treatment was last the values for water of imbibition were considerably reduced, although they were still higher than for samples cross-linked only. In general, the order of treatment affected values for wet crease recovery in a similar manner. It is suggested that the results obtained were caused by reaction at different sites in the cellulose chains of the treated samples. more...

The average values of n in cellulose-O(CH2O)n-cellulose, inter- and intramolecular bridges not differentiated, have been estimated in cotton fabrics treated by various methods. These values were obtained from n = 0.6 ÷ (1 - R), where R is the ratio of dry weight lost to formaldehyde lost, when formaldehyde was removed from the fabric by exposure to moist HCl vapor. The values estimated for n were 2.5, 2.4, 1.7, and 1.1 for Form W', Form D', Form V, and the alkaline methylenedisulfuric acid methods, respectively. more...

When freshly-harvested potatoes are treated with chemicals such as ethylene chlorhydrin, sodium thiocyanate, and thiourea the rest period is broken, and sprouts begin to make their appearance uniformly throughout the lot, after about five to eight days. The untreated potatoes planted at the same time, however, usually do not show sprouts until several weeks later, and even then the sprouting is not uniform (4). It seemed desirable to study the enzym changes that take place in the potatoes during these few days in which the processes correlated with the breaking of dormancy are in progress, and to compare them with untreated tubers under the same conditions. This paper presents the results of a series of measurements of the enzym activities of juices obtained from potatoes which had been treated with chemicals but which had not yet sprouted. The three chemicals used for treating the potatoes were ethylene chlorhydrin (ClCH2CH20H), sodium thiocyanate (NaSCN), and thiourea (NH2CSNH2). These, although quite unlike in chemical character, produce similar results in the breaking of dormancy and therefore it seemed of special interest to compare them with regard to their effects upon enzym activity. The object of the experiment was to obtain partial or complete answers to such questions as the following: What enzyms show the greatest changes? How soon after treatment do the changes start? Do the different chemicals produce the same or different effects upon the enzyms? Is there any relation between the concentration of chemical used in treating the potato and the enzym activity of the press-juice? Is there any correlation between the sprouting response and the enzym changes? Are the chemicals acting directly upon the enzyms or do the chemicals act first upon the living matter and only indirectly upon the enzyms? Do the changes occur in the absence of the eyes or must these be present to permit a response? The enzyms mainly studied in this series of experiments were catalase more...

A new phosphorus-containing ether of cellulose was prepared by the reaction of cotton with chloromethylphosphonic acid in the presence of sodium hydroxide. Phosphorus contents from 0.2% to 4.0% were obtained. By proper control of the phosphono methylation reaction, derivatives were made which ranged from water soluble to fibrous materials in which the physical properties of the untreated cotton were substantially unaltered. Phosphonomethyl cotton was flame resistant in the ammonium salt form and had a cation exchange capacity equivalent to some of the cation exchange resins. more...

Native cellulose dissolves in cuprammonium hydroxide solution, but, when it is crosslinked, it becomes a space polymer and is insoluble in this reagent. A method of detecting alkali-stable crosslinks in cotton is presented—the sample to be tested is shaken with cuprammonium hy droxide solution for 17 hr. If it dissolves completely, cellulose chains are not crosslinked, but, if it is partially insoluble, crosslinking is indicated. Partially insoluble cellulosic material appears in the cuprammonium hydroxide as granules that are easily detected visually.Cellulose was reacted with compounds which contained one or more groups that are reactive toward cellulose. In all cases the cellulosic derivatives made from cellulose and compounds that could crosslink it were partially insoluble in cuprammonium hydroxide. The compounds that were not capable of crosslinking cellulose produced derivatives soluble in cuprammonium hydroxide.Cotton was made insoluble in cuprammonium hydroxide by reacting it with formaldehyde, glyoxal, chloroethylsulfuric acid, α,γ-glycerol dichlorohydrin, a mixture of α,β- and α,γ-glycerol dichlorohydrin, tetrakis (hydroxymethyl) phosphonium chloride, compounds containing two or more N-methylol groups, 1,4-disulfato-2-butyne, and potassium (disulfatoethyl) amine. Aminized cotton, which is soluble in cuprammonium hydroxide, was made insoluble by cross linking it with either formaldehyde or tetrakis (hydroxymethyl) phosphonium chloride. more...

The red skins of peanut kernels contain a catecholtype tannin. The purified tannin represented about 7% of the weight of the skins. Much smaller quantities of phlobaphene and so-called “leuco-anthocyanic chromogen” were isolated from the skins. Some evidence of the presence of traces of a flavonic-type pigment was obtained. more...

Cotton fabric (80 × 80) was made crease resistant by processing with APO, tris(1-aziridinyl)phosphine oxide. Application was made by wetting the fabric with an aqueous solution of APO containing catalytic quantities of zinc fluoborate, squeezing out the excess with squeeze rolls, drying for 4 min. at 80-90° C., and curing for 4 min. at 140° C., followed by a good wash. An aftertreatment with a 1% Primenit VS2 solu tion increased the crease recovery angle. Monsanto crease angles of from 250° to more than 300° (warp + fill) have been obtained, depending on the resin add-on. The crease recovery is not changed much by home laundering. A loss of 30% in the Elmen dorf tearing strength was observed with samples with over 300° crease recovery angles. Creases durable to washing were obtained by drying the fabric with a hand iron followed by an oven cure. The resin could not be stripped from the fabric by methods that are effective with other resins. In addition to imparting crease resistance, this resin also imparts some degree of flame resistance. more...

1. Cottonseed was stored for over a year without appreciable change in red gossypol content by adjusting the moisture content to 8% or less and placing in closed containers at 1° or at −18°C. Cottonseed stored at room temperature, 27°C., showed a large increase in red gossypol content. 2. Cottonseed stored in the above manner at 1° or at −18°C. showed little or no increase in the non-gossypol absorption of the extracted oil at 236 mμ, the region of diene conjugation. This property of the extracted oil showed a large increase when cottonseed was stored at room temperature, 27°C. 3. Gossypol dissolved in cyclohexane has spectrophotometric extinction coefficients (concentration in g. per liter, solution depth 1 cm.) of 207, 70, and 40 at the maxima at 236 mμ, 286 mμ, and 358 mμ, respectively. 4. The extracted oil from peanuts stored for over four years at room temperature, 27°C., showed a much greater absorption in the region of 227 mμ to 234 mμ than did peanuts stored for the same time at 1° or at −18°C. more...

A new group of polymers made by reacting tris(1-aziridinyl)phosphine oxide, referred to as APO, or tris(1-aziridinyl)phosphine sulfide, referred to as APS, with tetrakis- (hydroxymethyl)phosphonium chloride, referred to as THPC, are good permanent-type flame retardants for cotton. All three of the compounds are water-soluble crystalline materials. The application of APO- or APS-THPC resins to textiles consists of padding fabric in an aqueous solution of the compounds, drying the fabric, curing it at about 140° C. for about 5 min. to polymerize the compounds, and then rinsing the fabric to remove any unpolymerized material. About 8% of the resins in 8-oz. cotton twill or sateen is adequate to make the fabric pass the vertical flame test before or after 15 launderings with synthetic detergents, followed by an acid fluoride sour after each laundering. The flame resistance is also very durable to boiling alkaline soap solutions. The properties of fabric treated with these new polymers are, in general, excellent. The hand and strength of the fabric is only slightly different from that of untreated fabric. The flame-resistant fabrics are resistant to rot and mildew. more...

Zirconium acetate binds certain phenols to cotton to impart a high degree of rot resistance. Pentachlorophenol, pentabromophenol, methylenebis( p-chlorophenol), and p-hydroxyphenylmercuric chloride have been applied in this way, either as the free phenols or as their sodium salts. This type of treatment has advantages over the simple deposition of phenols on cotton in that the bound phenols are resistant to extraction with water and organic solvents and to removal by abrasion. Besides being rot resistant, the treated fabrics exhibited a good hand, noticeable water repellency, and increased breaking strength, although their tearing strength was usually decreased. Fabrics having appreciable flame resistance resulted when sodium pentabromophenate was applied. Increased weight, softness, and water repellency were obtained on boiling the treated fabrics in soap solutions. This is evidence of an exchange of stearate anions for acetate anions in the polymeric zirconium oxyacetate matrix on the fabrics. more...

Cellulose formals cellulose-O(CH 2O) n-cellulose were made by reacting purified cotton yarn with formaldehyde in the presence of H218O. Average values for n were determined from the ratio of excess 18O in the formals to formaldehyde bi- functionally attached to the cellulose. Values of n ranging from 1.3 to 3.2 were obtained, depending on the reaction con ditions. The lower values of n were obtained at the lower formaldehyde concentrations, shorter reaction times, and elevated temperatures. A cellulose formal was made also by reacting cotton with the potassium salt of methylenedisul furic acid in the presence of H 218O and NaOH; its average n value was about 1.6. The n values obtained were compared with previously reported values obtained by determining the ratio of weight loss to formaldehyde loss when foremaldehyde was removed by exposure of the formals to moist HCl vapor and also with values obtained by H. Zollinger by permethyl ation, hydrolysis, and gas chromatography. more...

Raw cotton fiber in the form of card sliver was treated in an evacuated oven with the vapor of ethylenimine. The ethylenimine polymerized in or on the fiber and enhanced its ability to be dyed with acid dyes, but apparently there was little true chemical combination between the imine and the cellulose. Fiber treated in this way, along with appropriate controls, was con verted into fabric which was evaluated by various test methods. The results show that cotton may be treated with ethylenimine without adverse effect on the fabric made from it, but, aside from changed dyeing characteristics, no outstanding property has yet been noted for ethylenimine-treated cotton. more...