Nitric acid hno3

The concentrations of the elements Al, B, Ba, Ca, Cu, Fe, K, Li, Mg, Mn, Mo, Na, Ni, P, Pb, S, Sr, and Zn were determined by using a PerkinElmer Optima 3300 DV Inductively Coupled Plasma Optical Emission Spectrometer (ICP–OES) (PerkinElmer Inc., Waltham, MA, USA). This device is an echelle-grating-based ICP instrument, capable of determining the concentrations of multiple elements simultaneously.
The grain samples were ground, and then they were prepared by wet acid digestion. The digestion included two stages: predigestion and digestion. An amount of 1 g of oat grains was measured into a digestion tube, and 10 mL nitric acid (HNO₃, 69% v/v) (VWR International Ltd., Radnor, PA, USA) was added to the sample. After 12 h digestion, the samples were heated to 60 °C for 30 min in a LABOR MIM OE-718/A block digestion apparatus. Following the predigestion, after cooling for a few minutes, 3 cm³ of hydrogen-peroxide (H₂O₂, 30% v/v) (VWR International Ltd., Radnor, USA) was added to the samples. In the main digestion phase, the temperature was raised to 120 °C for 90 min. After digestion and cooling of the samples, the volume of the digested liquid was increased to 50 cm³ using ultrapore water (Milli Q two-level water purification system, Millipore S.A.S, Molsheim, France), and then filtered using Filtrak 388 filter paper, and then analysed by ICP-OES [53 (link)].

All solutions were prepared using analytical reagent grade chemicals and ultrapure water (18.2 MΩ cm⁻¹) prepared by Milli-Q™ Integral 5 Elix Technology (Merck Millipore, Saint Quentin in Yvelines, France). Nitric acid (HNO₃) (67% v/v, suprapur) was purchased from VWR (Fontenay-sous-Bois, France). The ICP-MS ultrapure grade (99.9995%) argon (Ar) and helium (He) were supplied by Linde (Montereau, France).
Intermediate standard solutions for calibration (Hg and Se) and internal standardization containing scandium (Sc) and bismuth (Bi) were prepared using 1000 mg/L individual stock solutions purchased from LGC Standards (Molsheim, France). Calibration standard solutions were prepared daily in 6% (v/v) HNO₃.
Certified reference materials (CRMs) ERM^®-BB-422 (fish muscle) from the European Joint Research Centre (JRC), 7402-a (codfish tissue) from the National Metrology Institute of Japan, and DOLT-5 (Dogfish liver tissue) and DORM-4 (fish protein) from the National Research Council Canada were all purchased from LGC Standards (Molsheim, France).

ECTFE base membrane with 0.1 μm nominal pore size, 0.69 porosity and 91 μm thickness; was procured from MilliporeSigma (Billerica, MA, USA). Potassium permanganate (KMnO₄) and nitric acid (HNO₃) were procured from VWR, Radnor, PA, USA. Deionized water was used throughout the investigation was collected from Thermo Fisher 18 MΩ Barnstead Smart2Pure system, Schwerte, Germany. The produced water (PW) was collected from Southwestern Energy sites, Virginia after hydraulic fracturing and prefiltration. This collected PW was used throughout the investigation without any further pretreatment. Table 1 summarizes the characterization of PW.

Carbopol type 974P (Carbomer Homopolymer Type B) introduced for use in mucosal applications (with moisture content 1.7 ± 0.2%) was received as a gift sample from Lubrizol (Cleveland, OH, USA). Commercially available vaginal mucoadhesive gel Replens™ was obtained from APC Institute (Warsaw, Poland). Porcine vaginal mucosa from white pigs weighting approximately 180 kg was attained from veterinary service of local slaughterhouse (Turośń Kościelna, Poland). Freshly excised tissue was washed and frozen at −20 °C immediately after the animal died [39 (link)]. Prior the test, samples were defrosted at ambient temperature and cut into 2 cm long and 2 mm thick pieces. Silver nitrate with purity 99.99%, sodium citrate and tannic acid were purchased from Sigma Aldrich (St. Louis, MO, USA). Triethylamine (TEA) and nitric acid (HNO₃) were obtained from Avantor Performance Materials (Gliwice, Poland).
Minimum Essential Medium with alpha modification (α-MEM), Dulbecco’s Modified Eagle Medium (D-MEM), fetal bovine serum (FBS), fetal calf serum (FCS), phosphate buffer saline (PBS), glutamine, penicillin and streptomycin were purchased from Life Sciences Technologies (Warsaw, Poland). Tissue DNA and cell culture DNA isolation kits were obtained from Eurx (Gdansk, Poland).

Boric acid (H₃BO₃), manganese chloride (MnCl₂), sodium hydroxide (NaOH), hydrochloric acid (HCl), nitric acid (HNO₃), and glacial acetic acid (CH₃COOH) were purchased from Avantor Performance Materials Poland S.A., Gliwice, Poland. All the reagents were analytically pure. Chitosan (CTS) (molecular weight of 600,000–800,000 g/mol) was purchased from Acros Organics (Geel, Belgium); the degree of deacetylation of CTS, as determined by means of a H¹ NMR method, was equal to 97%. Zirconium chloride (ZrCl₄) was purchased from Merck (Hohenbrunn, Germany). The wet-flue gas desulfurization (FGD) wastewater was obtained from the coal power plant with the composition shown in Table 1.

Capric acid (CA; purity degree: ≥ 98%; melting point: 27–32 °C), palmitic acid (PA; purity degree: ≥ 98%; melting point: 62–65 °C) and stearic acid (SA; purity degree: ≥ 98%; melting point: 67–72 °C) were obtained from Merck company (Germany), and used without further purifications. Thionly chloride (SOCl₂) and nitric acid (HNO₃) were purchased from BDH Chemicals Ltd. The CNTs were supplied from Cheap Tubes Inc. (Grafton, USA).

1-Octadecanol (OD; purity degree 95%) selected as organic PCM was procured from Sigma-Aldrich. Thionly chloride and nitric acid (HNO₃) were purchased from BDH Chemicals Ltd, and used as received. MWCNT was purchased from cheap tube USA, and used without any modification.