Is Precipitation of Aluminum Fast Enough to Explain Aluminum Deposition on Fish Gills?

1990 ◽  
Vol 47 (8) ◽  
pp. 1558-1561 ◽  
Author(s):  
Richard C. Playle ◽  
Chris M. Wood
Keyword(s):  
Soft Water ◽  
Peristaltic Pump ◽  
Final Solution ◽  
Solution Ph ◽  
Fish Gills ◽  
Polycarbonate Filter ◽  
Aluminum Deposition

A peristaltic pump was used to mix environmentally realistic concentrations of Al in soft water (14–15 °C) with 30 μM base (NH4OH) to simulate the alkalinization which occurs when acidic soft water passes over fish gills. Solutions were filtered under vacuum through 0.2 μm prerinsed filters using a polycarbonate filter apparatus. If final solution pH was [Formula: see text], only about 10% of total Al (159 μg∙L−1) was filtered from solution. If solution pH was raised from pH 5.3 to pH 5.7 with base, about 35% of Al was removed from solution, 1–4 s after the pH was raised. Similar results were obtained for 335 μg∙L−1 Al solutions. Production of additional Al retained by filters was fast enough to show that Al accumulation on fish gills may be partly due to polymerisation and precipitation of Al, as Al solubility is reduced in the more alkaline gill micro-environment.

The Influence of Adjusting Spray Solution pH on the Efficacy of Saflufenacil

2013 ◽  
Vol 27 (3) ◽  
pp. 445-447 ◽  
Author(s):  
Jared M. Roskamp ◽  
William G. Johnson
Keyword(s):  
Ammonium Sulfate ◽  
Weight Reduction ◽  
Seed Oil ◽  
Dry Weight ◽  
Final Solution ◽  
Solution Ph ◽  
Field Corn ◽  
Spray Solution ◽  
Initial Ph ◽  
Water Ph

Saflufenacil solubility and efficacy has been shown to be influenced by carrier water pH. This research was conducted to determine if altering the pH of a solution already containing saflufenacil would influence the efficacy of the herbicide. Saflufenacil at 25 g ai ha−1was applied to field corn in carrier water with one of five initial pH levels (4.0, 5.2, 6.5, 7.7, or 9.0) and then buffered to one of four final solution pH levels (4.0, 6.5, 9.0, or none) for a total of twenty treatments. All treatments included ammonium sulfate at 20.37 g L−1and methylated seed oil at 1% v/v. Generally, saflufenacil with a final solution pH of 6.5 or higher provided more dry weight reduction of corn than saflufenacil applied in a final pH of 5.2 or lower. When applying saflufenacil in water with an initial pH of 4.0 or 5.2, efficacy was increased by raising the final solution pH to either 6.5 or 9.0. Conversely, reduction in corn dry weight was less when solution pH of saflufenacil mixed in carrier water with an initial pH of 6.5 or 7.7 was lowered to a final pH of 4.0. When co-applying saflufenacil with herbicides that are very acidic, such as glyphosate, efficacy of saflufenacil may be reduced if solution pH is 5.2 or lower.

scholarly journals Characterization, Dissolution, and Solubility of Zn-Substituted Hydroxylapatites [(ZnxCa1−x)5(PO4)3OH] at 25°C

2017 ◽  
Vol 2017 ◽  
pp. 1-13
Author(s):  
Xin Zhao ◽  
Yinian Zhu ◽  
Zongqiang Zhu ◽  
Yanpeng Liang ◽  
Yanlong Niu ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Lattice Parameter ◽  
Batch Experiment ◽  
Molar Ratio ◽  
Final Solution ◽  
Free Energies ◽  
Solution Ph ◽  
Initial Ph ◽  
Zinc Concentrations ◽  
The Mean

A series of Zn-substituted hydroxylapatites [(ZnxCa1−x)5(PO4)3OH, Zn-Ca-HA] with the Zn/(Zn + Ca) molar ratio (XZn) of 0~0.16 was prepared and characterized, and then the dissolution of the synthesized solids in aqueous solution was investigated by batch experiment. The results indicated that the aqueous zinc, calcium, and phosphate concentrations greatly depended on the Zn/(Zn + Ca) molar ratio of the Zn-Ca-HA solids (XZn). For the Zn-Ca-HA dissolution at 25°C with an initial pH of 2.00, the final solution pH increased, while the final solution calcium and phosphate concentrations decreased with the increasing XZn. The final solution zinc concentrations increased with the increasing XZn when XZn≤0.08 and decreased with the increasing XZn when XZn = 0.08~0.16. The mean Ksp values for (ZnxCa1−x)5(PO4)3OH at 25°C decreased from 10−57.75 to 10−58.59 with the increasing XZn from 0.00 to 0.08 and then increased from 10–58.59 to 10–56.63 with the increasing XZn from 0.08 to 0.16. This tendency was consistent with the dependency of the lattice parameter a on XZn. The corresponding free energies of formation (ΔGfo) increased lineally from −6310.45 kJ/mol to −5979.39 kJ/mol with the increasing XZn from 0.00 to 0.16.

Germanium Co-Precipitation with Ferric Hydroxide: A Lab-Scale Study

2012 ◽  
Vol 581-582 ◽  
pp. 1050-1053
Author(s):  
Ke Yun Chen ◽  
Chen Liu ◽  
Duo Qiang Liang ◽  
Hang Jun He ◽  
Qiang Huang ◽  
...  
Keyword(s):  
Sulfuric Acid ◽  
Ferric Hydroxide ◽  
Sulfate Solution ◽  
Molar Ratio ◽  
Final Solution ◽  
Solution Ph ◽  
Acid Media ◽  
Dilute Sulfuric Acid ◽  
Co Precipitation ◽  
Germanium Concentration

Lab-scale germanium co-precipitation with ferric hydroxide in dilute sulfuric acid media was studied. The experiments of co-precipitation of germanium and ferric hydroxide were performed by neutralization of the germanium-ferric sulfate solution via adding calcium hydroxide powder. The variables affecting the germanium precipitation yield were investigated. The experimental results show that high initial germanium concentration, high ferric/germanium molar ratio, high final solution pH, low ion strength and slow temperature will contribute to high germanium precipitation yield.

scholarly journals Determining the Effect of Carrier Water pH and Bicarbonate Concentration on Final pH of Plant Growth Regulator Solutions

HortScience ◽  
2014 ◽  
Vol 49 (9) ◽  
pp. 1176-1182 ◽  
Author(s):  
Diane M. Camberato ◽  
James J. Camberato ◽  
Roberto G. Lopez
Keyword(s):  
Plant Growth ◽  
Gibberellic Acid ◽  
Plant Growth Regulators ◽  
Growth Regulators ◽  
Tap Water ◽  
Final Solution ◽  
Bicarbonate Concentration ◽  
Solution Ph ◽  
Chlormequat Chloride ◽  
Water Ph

Chemical plant growth regulators (PGRs) are important tools in greenhouse ornamental crop production because growers must increasingly meet specifications for plant shipping and marketability. However, the role of water quality parameters such as pH or alkalinity (bicarbonate in this study) on final PGR solution pH is not well documented and could impact efficacy. We assessed the interaction of PGR type and concentration on the final spray solution pH when combined with carrier water of varying pH and bicarbonate concentration. Eleven PGRs commonly used in floriculture (ancymidol, benzyladenine, chlormequat chloride, daminozide, dikegulac-sodium, ethephon, flurprimidol, gibberellic acid, gibberellic acid/benzyladenine, paclobutrazol, and uniconazole) at three concentrations (low, medium, and high recommended rates for each product) were added to reverse osmosis (RO) carrier water adjusted to four pH (5.3, 6.2, 7.2, 8.2) levels or added to tap carrier water adjusted to four bicarbonate concentrations (40, 86, 142, 293 mg·L−1 of CaCO3). Resultant solution pH levels were measured. Plant growth regulators were categorized as acidic, neutral, or basic in reaction based on the change of the carrier water pH on their addition. Benzyladenine, chlormequat chloride, gibberellic acid, and gibberellic acid/benzyladenine acted as weak acids when added to RO water, whereas daminozide, ethephon, and uniconazole reduced final solution pH from 1.25 to 5.75 pH units. Flurprimidol and paclobutrazol were neutral in reaction with final solution pH being similar to that of the RO carrier water before their addition. Ancymidol and dikegulac-sodium were basic in reaction, increasing final solution pH in RO carrier water up to 2.3 units. There was an interaction between chlormequat chloride concentration and RO carrier water pH on change in pH. When added to tap carrier water, final solution pH increased for all except the stronger acids, daminozide, ethephon, and uniconazole, where it decreased up to 3.5 units, and benzyladenine, where it decreased 0.35 units at 40 mg·L−1 bicarbonate. There was an interaction between PGR concentration and bicarbonate concentration in tap carrier water for daminozide and ethephon. The magnitude of change in pH (final solution pH minus initial carrier water pH) with the addition of each PGR was greater for RO than for tap water containing 40 to 293 mg·L−1 bicarbonate for all 11 PGRs tested.

The Ultrastructure of Monkey Gingival Epithelium

1967 ◽  
Vol 25 ◽  
pp. 16-17
Author(s):  
C.N. Sun
Keyword(s):  
Epithelial Cells ◽  
Macaca Nemestrina ◽  
Stratum Granulosum ◽  
Solution Ph ◽  
Gingival Epithelial Cells ◽  
Stratum Spinosum ◽  
Cell Layers ◽  
Gingival Epithelium ◽  
The Individual ◽  
Different Thickness

The present study demonstrates the ultrastructure of the gingival epithelium of the pig tail monkey (Macaca nemestrina). Specimens were taken from lingual and facial gingival surfaces and fixed in Dalton's chrome osmium solution (pH 7.6) for 1 hr, dehydrated, and then embedded in Epon 812.Tonofibrils are variable in number and structure according to the different region or location of the gingival epithelial cells, the main orientation of which is parallel to the long axis of the cells. The cytoplasm of the basal epithelial cells contains a great number of tonofilaments and numerous mitochondria. The basement membrane is 300 to 400 A thick. In the cells of stratum spinosum, the tonofibrils are densely packed and increased in number (fig. 1 and 3). They seem to take on a somewhat concentric arrangement around the nucleus. The filaments may occur scattered as thin fibrils in the cytoplasm or they may be arranged in bundles of different thickness. The filaments have a diameter about 50 A. In the stratum granulosum, the cells gradually become flatted, the tonofibrils are usually thin, and the individual tonofilaments are clearly distinguishable (fig. 2). The mitochondria and endoplasmic reticulum are seldom seen in these superficial cell layers.

Revealing gross three-dimensional structure in the SEM

1987 ◽  
Vol 45 ◽  
pp. 656-657
Author(s):  
Sterling P. Newberry
Keyword(s):  
Freeze Drying ◽  
Three Dimensional ◽  
Dimensional Structure ◽  
Small Object ◽  
Final Solution ◽  
Dimensional Representation ◽  
X Ray ◽  
Three Dimensional Representation ◽  
Freeze Dried ◽  
Critical Point Drying

The beautiful three dimensional representation of small object surfaces by the SEM leads one to search for ways to open up the sample and look inside. Could this be the answer to a better microscopy for gross biological 3-D structure? We know from X-Ray microscope images that Freeze Drying and Critical Point Drying give promise of adequately preserving gross structure. Can we slice such preparations open for SEM inspection? In general these preparations crush more readily than they slice. Russell and Dagihlian got around the problem by “deembedding” a section before imaging. This some what defeats the advantages of direct dry preparation, thus we are reluctant to accept it as the final solution to our problem. Alternatively, consider fig 1 wherein a freeze dried onion root has a window cut in its surface by a micromanipulator during observation in the SEM.

UV Curable Organic-Inorganic Hybrid Materials

2000 ◽  
Vol 628 ◽  
Author(s):  
Guang-Way Jang ◽  
Ren-Jye Wu ◽  
Yuung-Ching Sheen ◽  
Ya-Hui Lin ◽  
Chi-Jung Chang
Keyword(s):  
Hybrid Materials ◽  
Colloidal Silica ◽  
Sol Gel ◽  
Solution Ph ◽  
Uv Curable ◽  
Inorganic Hybrid ◽  
Degradation Temperature ◽  
Sol Gel Process ◽  
The Stability ◽  
Thermal Degradation Temperature

This work successfully prepared an UV curable organic-inorganic hybrid material consisting of organic modified colloidal silica. Applications of UV curable organic-inorganic hybrid materials include abrasion resistant coatings, photo-patternable thin films and waveguides. Colloidal silica containing reactive functional groups were also prepared by reacting organic silane and tetraethyl orthosilicate (TEOS) using sol-gel process. In addition, the efficiency of grafting organic moiety onto silica nanoparticles was investigated by applying TGA and FTIR techniques. Experimental results indicated a strong interdependence between surface modification efficiency and solution pH. Acrylate-SiO2 hybrid formation could result in a shifting of thermal degradation temperature of organic component from about 200°C to near 400°C. In addition, the stability of organic modified colloidal silica in UV curable formula and the physical properties of resulting coatings were discussed. Furthermore, the morphology of organic modified colloidal silica was investigated by performing TEM and SEM studies‥

Role of Phospholipids of Fish Gills in Forming of Toxic Resistance to Cadmium Ions

2016 ◽  
Vol 52 (4) ◽  
pp. 74-80
Author(s):  
Yu. I. Senyk ◽  
V. O. Khomenchuk ◽  
V. Z. Kurant ◽  
V. V. Grubinko
Keyword(s):  
Fish Gills ◽  
Cadmium Ions

Irrigation Volume, Application, and Controlled-release Fertilizer II. Effect on Substrate Solution Nutrient Concentration and Water Efficiency in Containerized Plant Production

1998 ◽  
Vol 16 (3) ◽  
pp. 182-188
Author(s):  
Kelly M. Groves ◽  
Stuart L. Warren ◽  
Ted E. Bilderback
Keyword(s):  
Controlled Release ◽  
Irrigation Efficiency ◽  
Plant Production ◽  
Water Efficiency ◽  
Solution Ph ◽  
Entire Study ◽  
Once Daily ◽  
Substrate Solution ◽  
Irrigation Volume ◽  
Controlled Release Fertilizers

Abstract Rooted cuttings of Cotoneaster dammeri Schneid ‘Skogholm’ and seedlings of Rudbeckia fulgida Ait. ‘Goldsturm’ were potted into 3.8 liter (4 qt) containers in a pine bark:sand (8:1 by vol) substrate incorporated with 3.5 g (0.12 oz) N per container provided by one of the following five controlled-release fertilizers (CRFs): Meister 21N–3.5P–11.1K (21–7–14), Osmocote 24N–2.0P–5.6K (24–4–7), Scotts 23N–2.0P–6.4K (23–4–8), Sustane 5N–0.9P–3.3K (5–2–4) or Woodace 21N–3.0P–9.5K (21–6–12). Two hundred ml (0.3 in), 400 ml (0.6 in), 800 ml (1.1 in) or 1200 ml (1.7 in) of water was applied once daily (single) or in two equal applications with a 2 hr interval between applications (cyclic). Substrate solutions were collected from containers of cotoneaster 15, 32, 45, 60, 74, 90, 105, and 119 days after initiation (DAI). Irrigation efficiency [(water applied − water leached) ÷ water applied] was determined on the same days. Cyclic application improved irrigation efficiency at 800 ml (1.1 in) and 1200 ml (1.7 in) ≈ 27% compared to a single application. Irrigation efficiencies averaged over the season were 95%, 84%, 62%, and 48% for cotoneaster and 100%, 90%, 72%, and 51% for rudbeckia at 200 ml (0.3 in), 400 ml (0.6 in), 800 ml (1.1 in) and 1200 ml (1.7 in), respectively. NH4-N and NO3-N and PO4-P concentrations in substrate solution decreased with increasing irrigation volume regardless of CRF. Substrate NH4-N concentration decreased throughout the season with most CRFs below 5 mg/liter by 90 DAI. CRFs mainly affected substrate NH4-N and NO3-N concentrations when irrigated with 200 ml (0.3 in) or 400 ml (0.6 in). Substrate NH4-N, NO3-N, and PO4-P solution concentrations were similar for all CRFs at irrigation volume of 1200 ml (1.7 in). Osmocote, Scotts, and Woodace maintained relatively constant substrate solution levels of PO4-P through 60 DAI. By 90 DAI, substrate PO4-P levels were similar regardless of irrigation volume or CRF. Substrate PO4-P concentrations were never in the recommended range of 5 to 10 mg/liter when irrigated with 800 ml (1.1 in) or 1200 ml (1.7 in) regardless of CRF. Solution pH remained in the recommended range of 5.0 to 6.0 for all irrigation volumes and CRFs throughout the entire study with the exception of Sustane.

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