Acid Soaking Research Articles

Study of the electrokinetic process on Cd and Pb spiked soils

This study examined three soil samples from different locations of Taiwan. According to those results, soil from Kaohsung County (KH) is weak basic clay loam with the highest cation exchange capacity (CEC) among all samples. Soil from a Cd contaminated paddy field in Kuanyin village, Taoyuan County (TY) is neutral loamy sand. And, Latosol soil from National Pingtung University of Science and Technology campus in Pingtung County (PT) is acidic clay. Tested samples without heavy metal spiked have low total (aqua regia digested) Cd contents; the natural Pb contents are all lower than 50 mg/kg. All samples can adsorb more Pb than Cd. The order of soils adsorption capacity on Cd and Pb is as follows: KH clay loam>TY loamy sand>PT clay. In addition, electrokinetic experiments were performed on Cd and Pb spiked and 0.1 M HCl saturated TY soil, indicating it to be the optimum Cd and Pb removal efficiency, PT soil is the second and KH soil is the worst. In contrast with all samples saturated in water, dilute HCl soaking facilitated the Cd and Pb removal during the electrokinetic process. The process did not influence Cd and Pb in the spiked KH soil. In water saturated spiked TY soil, Cd and Pb exist in highly stable forms in soil near cathode during the experiment. Acid soaking not only reduced the formation of the high Cd concentration suspension, but also assisted quite effectively in concentrating the Cd and Pb in the zone near cathode in stable residual and carbonate forms. Cd spiked and water saturated PT soil sample clearly demonstrated that Cd is concentrated in soil near the cathode after electrokinetic process. When soaking with 0.1 M HCl during the process, even better results were obtained. However, the exchangeable Cd in the soil near cathode is extremely high, thereby requiring further treatments. The Pb spiked water saturated PT soil displayed no change in Pb forms after the electrokinetic process. When soaked with 0.1 M HCl, the electrokinetic process yielded excellent results. In addition, spiked PT soil in 0.1 M HCl also has lower Cd and Pb stabilities during electrokinetic process. Moreover, elongating the process time may enhance the removal efficiency.

Effects of perturbations and stimulants on red raspberry (Rubus idaeusL.) seed germination

Red raspberry (Rubus idaeus L.) seeds germinate only after seed coats are degraded. In nature this happens slowly. Seeds from recently collected fruit (fresh to four years old) germinated only after scarification of the seed coat by 20-minute soaking in concentrated sulfuric acid. Germination was not enhanced by: (1) short-term intermittent soaking, up to 81 hours, in dilute (0.01 normal) hydrochloric acid; (2) passage through the digestive tracts of bears, coyotes, or birds; (3) physical perturbations such as nicking, mechanical scarification, repeated freezing and thawing and/or four years of exposure in the field; (4) exposure to light; (5) increased temperatures or temperature fluctuations; or (6) addition of nitrogen (ammonium nitrate, urea). Key words: animal passage, germination, nitrogen, red raspberry, Rubus idaeus L., seed coat, seed weight, scarification, stratification

Methods for removing epiphytes from seagrasses: SEM observations on treated leaves

Several techniques commonly used to remove epiphytes from seagrasses were tested on the same Posidonia oceanica (L.) Delile material: shaking, scraping, sonicating and soaking in acid. The effects of each treatment on the epiphyte removal rate and on the seagrass itself were assessed by scanning electron microscopy. The advantages and disadvantages of each technique are discussed. It appears that the combination of an acid treatment with moderate scraping provides the best results as nearly all epiphytes are removed without seriously damaging the leaf substratum.

Effect of processing on some antinutritional factors of lentils

Changes in the trypsin inhibitor activity and in the phytic acid, tannin, and catechin content of lentils (Lens culinaris var. Vulgaris) were investigated after soaking in distilled water, citric acid, and sodium bicarbonate solutions. The effect of cooking, after the seeds were presoaked in the above-mentioned solutions and both the soaking and cooking solutions were discarded, was also studied. Finally, two varieties of lentils (L. culinaris var. Vulgaris and Variabilis) were germinated for 6 days, and the effect on the trypsin inhibitor activity and the phytic acid, tannin, and catechin contents was also measured. Soaking did not modify the trypsin inhibitor activity, decreased the phytic acid content, and increased the tannin and catechin contents. Cooking the presoaked seed brought about the total removal of trypsin inhibitor activity, a reduction of the phytic acid level, and an increase of the content of tannins and catechins. The trypsin inhibitor activity and the phytic acid content showed a large decrease after 6 days of germination, while amounts of tannins and catechins in the two lentil varieties studied increased. Cooking and germination seem to be good procedures to improve the quality of lentil flour from the nutritional point of view, despite the fact that a large variation on the effects of processing, related to the different legume varieties, has been observed.

THE EFFECT OF PRE-TREATMENTS AND DIURNAL TEMPERATURE VARIATIONS ON THE GERMINATION OFJUNIPERUS EXCELSA

SUMMARY One-year old seed of Juniperus excelsa M. Bieb. from western Kenya was screened, pretreated and sown and germination percentage assessed after 18 weeks. Germination percentage was low at a maximum of 21%. Treatments included soaking in gibberellic acid, hydrogen peroxide, and sulphuric acid; stratification for 60 days; hot water treatments; and abrasion. All pre-treatments failed to significantly increase germination percentages. All hot water treatments produced no germination. A diurnal variation in temperature (20/30°C) produced significantly higher germination percentages than a constant 25°C.

Effect of Dilute Acid on the Accelerated Weathering of Wood

Western red cedar (Thuja plicata) specimens were soaked in acid solutions to determine the effect of acid conditions (such as low pH fog) on the weathering of wood. Daily 1-hour soaking in dilute sulfurous, sulfuric, or nitric acid (pH 2.0, 2.5, 3.0, 3.5, or 4.0) increased the rate of accelerated (xenon arc) weathering of the specimens compared to controls soaked in distilled/deionized water. Weathering was manifested as the erosion rate of the wood surface and was determined gravimetrically be fitting the weight loss over time to a linear model. This method detected significant differences between acid-treated specimens and untreated controls within 300 hours of accelerated weathering. The erosion rate was dependent on the acid type and pH. Sulfurous acid treatment caused the fastest rate of erosion, followed by sulfuric then nitric acid. None of the acids affected the erosion rate at pH 3.5 or above. Below this threshold, the rate of erosion increased as the hydrogen ion concentration increased. Sugar analysis of residues from the acids and the distilled water used to soak the wood indicated acid-dependent degradation of polysaccharides.

The preparation of palladium metal catalysts supported on carbon part I: Selection and treatment of the carbons

Carbons are widely used as supports for precious metal catalysts. The carbon should be carefully chosen to have a high area and a minimum of micropores. A number of commercial carbons have been chosen and examined by nitrogen adsorption to determine their surface properties. Some of the carbons have been subjected to carbon burnoff, acid soaking, and/or deposition of carbon via a polymer. Changes in surface properties are brought about by burnoff, but the carbons retain a large proportion of microporosity, although mesopore volume is increased. Acid washing does not have a significant effect on area or pore volume. Deposition of carbon results in pore volume decrease including volume of micropores.

Dormancy and Field Burial of Cowpea (Vigna unguiculata) Seed

Seed dormancy and soil longevity characteristics of three weedy cowpea [Vigna unguiculata(L.) Walp.] cultivars were investigated. Seed germination was maximum at 40 C; however, ‘Clay’ had greater germination than ‘Black’ or ‘Red Ripper’ cowpea at temperatures ≥ 20 C. Concentrated sulfuric acid soaks, hot (70 C)-water soaks, and piercing the seed coat promoted germination. Seed with an initial water content of 12.3% were stored at relative humidities ranging from 0 to 60% at 25 C. After 4 weeks of storage at relative humidities of 0 to 50%, seed water content varied from 4.6 to 11.4%. Germination and hard seed content was 11% or more and 89% or less, respectively, for seed with water content ranging from 6.9 to 11.4%. Except for seed with an initial water content of 6.9%, cowpea seed water content increased after 3 weeks of storage in a 70% relative humidity environment. Rehydration increased germination for seed with initial water content of 9.2% or more, but not for seed with initial water content of 8.4% or less. In mid-November 1981 and 1982, Black, Clay, Red Ripper, and sicklepod (Cassia obtusifoliaL. # CASOB) seed were buried at soil depths of 2.5, 7.5, and 15 cm for 3, 6, and 9 months. Seed survival of Black and Red Ripper was similar to that of sicklepod; however, longevity of Clay seed was less than sicklepod. Survival was greater for seed buried in 1981 than in 1982 because of low seed water content of the 1981 seedlots.

Gibberellic acid soak treatments for fully-cooled tulips

In attempts to reduce the glasshouse period of fully-cooled 5°C-forced tulips, ‘Apeldoorn’ bulbs were soaked before planting in aerated and non-aerated gibberellic acid (GA 3) solutions for 2–48 h. A 48-h treatment with 250–500 mg l −1 GA 3 was the most effective, giving a glasshouse period 7–11 days shorter than for untreated bulbs. Soaks for 24 and 48 h caused root emergence, and 48-h soaks caused perianth segment splitting in one experiment. Aerated or non-aerated GA 3 solutions gave similar results. Soaking in water alone gave a smaller increase in earliness. In general, a shortened glasshouse period was associated with shorter whole stem and last internode lengths. In GA 3 treatments, flower losses were lower than for distilled water treated and untreated bulbs. A practical treatment would be a non-aerated soak for 24 h with between 250 and 500 mg l −1 GA 3.

Improving germination of hop-hornbeam seeds

The effects of stratification, clipping, sulfuric acid soaking, and pericarp removal on the germination of hop-hornbeam (Ostryavirginiana [Mill.] K. Koch) seeds were investigated. Untreated seeds failed to germinate. Removing the pericarp produced 34–37% germination. Gibberellic acid (GA3) improved germination of intact seeds, but was most effective for seeds with pericarps removed, resulting in 76–80% germination. Although stratification of intact seeds for 3 months produced 15% germination, a combination of pericarp removal, GA3 treatment, and stratification was best, resulting in 81% germination. For seed testing, the pericarps should be removed and seeds treated with 500 mg/L GA3 for 24 h at 20 °C. Germination at 20 °C with continuous light appears to be a good test condition.

Preparation of Fungal-free Seedlings of Magnolia grandiflora L.1

Abstract A method is proposed for the germination of fungal-free seeds of Magnolia grandiflora as a source of tissue for in vitro experiments. A combination sequence of a 16 hour water-soak at 25°C, hot water (52°C) for 1 hour, and then surface sterilization for 1 hour in 1:1000 aqueous mercuric chloride was the best treatment. Dips in 2.5% chlorox, 95% ethyl alcohol and concentrated sulfuric acid soak for 20 minutes were unsatisfactory. If seeds are selected carefully and treated as described, 60 to 90% of the seeds will germinate aseptically within 30 days.

A study of sintered apatites.

Hydroxyapatite, fluorapatite, and chlorapatite materials were synthesized and their sintering characteristics were studied. The compressive strength of the apatites was determined and is given as a function of density. Scanning electron micrographs of the typical material structure are given. The degradation of strength of the hydroxyapatite after an extended acid soak also is reported.

Short Soaking in Gibberellic Acid Promotes Tree Seed Germination

Gibberellins have been shown to promote seed germination of various hardwood and coniferous trees by overcoming dormancy (1-7). This note reports results of a study undertaken to determine effects of gibberellic acid (GA-3) on rate and capacity of germinmation of tree seed soaked in a high concentration of the hormone for a short time. In this completely randomized experiment 2 levels of gibberellic acid (GA-3) were applied to seed that had been stored for at least 6 months. Seed was soaked 12 hours in an aqueous solution of a 75 percent potassium salt at 250 or 500 ppm. A control was soaked only in distilled water. Twenty-five seed of a single species were placed on filter paper in Petri dishes and kept moist with distilled water. Four replications of each treatment were placed on a countertop in an air conditioned room kept at approximately 20°C. Table 1. Germination of individual species seed after soaking 12 hours in GA-3.

Softening Techniques for Nail Biopsies

Different methods of softening nail specimens for histologic sectioning were compared. For nails of normal thickness, several methods were equally effective, namely, soaking in potassium hydroxide or nitric acid after fixation in formaldehyde solution or Polysorbate 40 (Tween 40) treatment of normally processed paraffin blocks. For thick nails treatment with polysorbate 40 was preferred, although potassium hydroxide was adequate.

Influence of Antioxidants and Salinity Stress on Seed Viability Characters of Some Wheat Cultivars

To explore the impact of antioxidants types and levels prim on seed germination characters of some bread wheat cultivars under salinity stress. An experiment accompanied in seed science lab during November and December 2016, to study the response of antioxidants seed prim of some bread wheat cultivars to germinate under salinity levels. The highest of final percentages of germination (96.8 %), higher percentages of germination energy (58.11 %), highest values of germination index (0.970) and a smaller amount of germination time (2.29 day) obtained from sown Misr 1 variety. The results showed that maximum of percentages of germination (91.15 %) and germination index (0.951) obtained from soaking in humic acid. The maximum percentages of energy of germination (41.21 %) and the less mean germination time (2.77 day from soaking grains in ascorbic acid compared with without antioxidants. Increasing antioxidant concentrations to 200 ppm produced the highest percentages of germination (91.61 %), energy of germination (37.63 %), germination index (0.953) and the lowermost of mean germination time (2.97 day) compared with without antioxidants and level of 100 ppm. Increasing salinity to 160 mM during germination of wheat cultivars significantly reduced percentages of germination by 18.5 %, energy of germination by 96.7 %, germination index by 18.6 % and mean germination time by 53.5 % compared with without salinity (control). Whereas, for reducing the gap between production and consumption, it could be recommended that soaking bread wheat in humic acid or ascorbic acid at 200 mM under salinity stress enhanced seed viability and advise to sown under saline new reclaimed soil.

Studies on udo, Aralia cordata THUNB. (1)

1. Studies were carried out in 1955, in order to investigate the dormancy of seeds of domestic and wild udos (Aralia cordata THUNB.) gathered in Japan. 2. Udo seeds scarecely germinated immediately after harvesting and when they had been in dry storage, while seeds stored in the cold wet sand germinated well. Domestic udo seeds germinated more easily than wild ones. 3. Chilling treatments (0_??_2°C) were very effec-tive to break the dormancy of udo seeds in dry storage. In this case also, domestic udo seeds germinated more easily than wild ones. Varietal differences were observed in the dormancy of do-mestic udo seeds, while there were wide variations in wild ones. 4. Injuring seed coats, soaking in the concen-trated sulphuric acid, thiourea treatment (0.2%), alternating temperature, and washing in the running water were not effective to break the dormancy. Light had no decisive effect on the germination.

Studies on udo, Aralia cordata THUNB. (2)

1. Studies were carried out in 1955, in order to investigate the dormancy of seeds of domestic and wild udos (Aralia cordata THUNB.) gathered in Japan. 2. Udo seeds scarecely germinated immediately after harvesting and when they had been in dry storage, while seeds stored in the cold wet sand germinated well. Domestic udo seeds germinated more easily than wild ones. 3. Chilling treatments (0_??_2°C) were very effec-tive to break the dormancy of udo seeds in dry storage. In this case also, domestic udo seeds germinated more easily than wild ones. Varietal differences were observed in the dormancy of do-mestic udo seeds, while there were wide variations in wild ones. 4. Injuring seed coats, soaking in the concen-trated sulphuric acid, thiourea treatment (0.2%), alternating temperature, and washing in the running water were not effective to break the dormancy. Light had no decisive effect on the germination.

Treatment of Rhus dermatitis with topical hydrocortisone; a clinical evaluation.

THE FAILURE of older remedies—boric acid or permanganate soaks; topical antihistamines; calamine lotion; and superficial anesthetic agents—to prevent spread and to alleviate symptoms of Rhus dermatitis has led to the recent study of corticotropin (adrenocorticotropic hormone) and cortisone in this condition. At the present time a divided opinion exists as to the value of these agents in this disease. Such a variance in reported results can be appreciated by a consideration of the nature of Rhus dermatitis, especially the protean course of the disease in different individuals. In the treatment of 15 patients with Rhus dermatitis by the use of 500 to 1000 mg. of oral cortisone over a four- to seven-day period, Wrong and Smith noted a good to excellent response in 73% of their cases. Falk reported a series of nine patients hospitalized because of Rhus dermatitis. These patients were treated for three days with either oral cortisone