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Calcium-nitrate-based transparent completion fluids are widely used in the oil and gas industry for well completion and stimulation operations in carbonate reservoirs. These fluids have many advantages, such as medium density, low corrosion, good temperature stability, low clay swelling, and high wettability. However, the density of calcium nitrate brine is limited by its solubility, which can be increased by the addition of alcohols. This study investigated the effects of adding different types of alcohols (G1, G2, and G3) to calcium nitrate brine on the properties and performance of the completion fluid for carbonate reservoirs. The fluid properties and performance were evaluated through a series of laboratory tests, including density measurement, corrosion test, viscosity measurement, rheology test, temperature stability test, clay swelling test, wettability test, and compatibility test. The results showed that the addition of alcohols to brine can improve or reduce the fluid density, viscosity, corrosion, temperature stability, clay swelling, wettability, and compatibility, depending on the type and amount of alcohols. The optimum fluids have been selected based on their highest density, lowest viscosity, lowest corrosion, highest temperature stability, lowest clay swelling, highest wettability change, and highest compatibility with formation fluids. The densities of the fluids CN 4 , CNG1 4 , CNG2 4 , and CNG3 4 were respectively 96, 101, 101.5, and 100 pounds per cubic foot (pcf). Their rates of corrosion on L80 steel were respectively 0.829, 0.589, 0.720, and 0.599 mils per year (mpy). Their apparent viscosities at 62.4 °F were respectively around 15, 120, 100, and 60 centipoise (cp). Their apparent viscosities at 176 °F were all around 10 to 25 mpy. The fluids remained clear with no evidence of suspended solid particles at 20 °F, indicating their resilience to low-temperature conditions and suitability for use in cold weather operations. The fluid CNG2 4 becomes cloudy at 285 °F, and the fluid CNG3 4 becomes cloudy from 212 °F onward, but the CN 4 fluid remains clear and transparent at all temperatures. In the tested high temperatures, the effect on their pH was around the same. The fluids CN 4 , CNG2 4 , and CNG3 4 had a lower swelling index than 5 ml per 2 g of bentonite clay. The contact angles of oil and carbonate-type thin sections after their wettabilities were affected by the fluids were also 99.5, 36.54, and 46.03°, respectively. Finally, they’re all relatively compatible with formation fluids. The best completion fluid for carbonate reservoirs was CNG2 4 , which contained calcium nitrate and G2 alcohol. This fluid had the best overall performance and safety of the fluids tested.

Abstract A replicated 5 × 5 Latin square design with a 2 × 2 + 1 factorial arrangement of treatments was used to determine the effects of bismuth subsalicylate (BSS) and encapsulated calcium ammonium nitrate (eCAN) on ruminal fermentation of beef cattle consuming bahiagrass hay (Paspalum notatum) and sugarcane molasses. Ten ruminally cannulated steers (n = 8; 461 ± 148 kg of body weight [BW]; average BW ± SD) and heifers (n = 2; 337 ± 74 kg of BW) were randomly assigned to one of five treatments as follows: 1) 2.7 g/kg of BW of molasses (NCTRL), 2) NCTRL + 182 mg/kg of BW of urea (U), 3) U + 58.4 mg/kg of BW of BSS (UB), 4) NCTRL + 538 mg/kg of BW of eCAN (NIT), and 5) NIT + 58.4 mg/kg of BW of BSS (NITB). With the exception of NCTRL, all treatments were isonitrogenous. Beginning on day 14 of each period, ruminal fluid was collected and rectal temperature was recorded 4× per day for 3 d to determine ruminal changes every 2 h from 0 to 22 h post-feeding. Ruminal gas cap samples were collected at 0, 3, 6, 9, and 12 h on day 0 of each period followed by 0 h on days 1, 2, 3, and 14. Microbial N flow was determined using Cr-Ethylenediaminetetraacetic acid, YbCl3, and indigestible neutral detergent fiber for liquid, small particle, and large particle phases, respectively. Data were analyzed using the MIXED procedure of SAS. Orthogonal contrasts were used to evaluate the effects of nonprotein nitrogen (NPN) inclusion, NPN source, BSS, and NPN source × BSS. There was no treatment effect (P > 0.05) on concentrations of H2S on day 0, 1, 2, or 14; however, on day 3, concentrations of H2S were reduced (P = 0.018) when NPN was provided. No effect of treatment (P = 0.864) occurred for ruminal pH. There was an effect of NPN source on total concentrations of VFA (P = 0.011), where a 6% reduction occurred when eCAN was provided. There were effects of NPN (P = 0.001) and NPN source (P = 0.009) on the concentration of NH3-N, where cattle consuming NPN had a greater concentration than those not consuming NPN, and eCAN reduced the concentration compared with urea. Total concentrations of VFA and NH3-N were not affected (P > 0.05) by BSS. There was an effect of BSS (P = 0.009) on rectal temperature, where cattle not consuming BSS had greater temperatures than those receiving BSS. No differences for NPN, NPN source, nor BSS (P > 0.05) were observed for microbial N flow. In conclusion, eCAN does not appear to deliver equivalent ruminal fermentation parameters compared with urea, and BSS has limited effects on fermentation.

Background Secondary soil salinization adversely affects plant growth in greenhouse in China. Previous studies have suggested that the putative molybdate transporter SlMOT2 may be involved in nitrate stress tolerance in tomatoes. However, the precise regulatory mechanisms remain unclear. Results Calcium nitrate stress significantly induced the expression of the SlMOT2 gene. In comparison with wild-type (WT) plants, SlMOT2 -overexpressing (OE) plants exhibited enhanced tolerance to nitrate stress, as evidenced by lower malondialdehyde (MDA) content, reduced hydrogen peroxide (H₂O₂) accumulation, decline in nitrate accumulation, significantly increased antioxidant enzyme activity, and a higher net photosynthetic rate under nitrate stress conditions, whereas slmot2 knockout mutant plants showed nitrate stress sensitivity. An increasing sulfur level and less nitrate content were also found in overexpression lines of SlMOT2 under calcium nitrate stress. Transcriptomic analysis revealed that nitrate stress induced the upregulation of numerous genes, with the differentially expressed genes (DEGs) in OE plants being significantly enriched in phenylpropanoid biosynthesis, abscisic acid (ABA) synthesis, amino sugar and nucleotide sugar metabolism, and amino acid metabolism in comparison with WT plants. Conclusions The SlMOT2 gene confers nitrate stress tolerance in tomato plants, likely through the following molecular mechanisms: (1) enhancing the biosynthesis of antioxidant compounds to improve reactive oxygen species (ROS)-scavenging capacity and maintain photosynthetic efficiency;(2) activating plant hormone signaling transduction pathways to potentiate stress responses; (3) promoting sulfate uptake to rebalance excess nitrogen in planta, thereby establishing a new nitrogen-sulfur homeostasis. These findings establish a theoretical framework for improving nitrate stress resistance during tomato cultivation.

In this paper, the characteristics of new porous coatings fabricated at three voltages in electrolytes based on H3PO4 with calcium nitrate tetrahydrate, magnesium nitrate hexahydrate, and copper(II) nitrate trihydrate are presented. The SEM, energy dispersive spectroscopy (EDS), glow discharge optical emission spectroscopy (GDOES), X-ray photoelectron spectroscopy (XPS), and XRD techniques for coating identification were used. It was found that the higher the plasma electrolytic oxidation (PEO) (micro arc oxidation (MAO)) voltage, the thicker the porous coating with higher amounts of built-in elements coming from the electrolyte and more amorphous phase with signals from crystalline Ca(H2PO4)2∙H2O and/or Ti(HPO4)2∙H2O. Additionally, the external parts of the obtained porous coatings formed on titanium consisted mainly of Ti4+, Ca2+, Mg2+ and PO43−, HPO42−, H2PO4−, P2O74− as well as Zn2+ or copper Cu+/Cu2+. The surface should be characterized by high biocompatibility, due to the presence of structures based on calcium and phosphates, and have bactericidal properties, due to the presence of zinc and copper ions. Furthermore, the addition of magnesium ions should accelerate the healing of postoperative wounds, which could lead to faster patient recovery.

Best management practices for N fertilization should increase yields while reducing negative environmental effects such as losses by ammonia (NH 3 ) volatilization and emission of greenhouse gases, especially nitrous oxide (N 2 O). We studied the impact on sugarcane of two N sources (UR: urea and CAN: calcium ammonium nitrate) in three N rates (30, 60, and 90 kg N ha −1 in the plant cane cycle and 60, 120, and 180 kg N ha −1 in ratoons) on a sugarcane field grown on a Red Latosol soil in southeastern Brazil. We measured sugarcane yields and N 2 O, CO 2 and CH 4 emissions in three crop cycles (plant cane, 2nd and 3rd ratoons), and NH 3 in two crop cycles (2nd and 3rd ratoons). The accumulated emission of N 2 O from UR was significantly higher in comparison with those of CAN in all three crop cycles. The average emission factors for UR were 0.8% (plant cane), 1.1% (2nd ratoon) and 0.8% (3rd ratoon) and the corresponding figures for CAN were 0.4%, 0.7% and 0.5%, respectively. The N 2 O intensity was higher for UR (20.3 mg N–N 2 O kg −1 sugarcane stalk) than CAN (16.2 mg N–N 2 O kg −1 sugarcane stalk). The NH 3 volatilization losses for CAN were less than 1% compared to 5–16% of the N applied as UR. Stalk yield increased with N application, but no difference was observed between UR and CAN. We concluded that CAN has the potential to reduce both NH 3 and N 2 O losses compared with urea and is the preferred N source for sugarcane.

For political and environmental reasons, there is an urgent need for alternatives to energy-intensive synthetic fertilizers. One solution is the targeted recycling of nutrients within agriculture. In this study, liquid ammonium sulphate (LAS) as a recycling product derived from digestate treatment was compared to calcium ammonium nitrate, manure and original digestates in an on-farm experiment using a participatory approach. Based on regular meetings with the farmers involved, a flexible experimental design was developed which integrated the fertilization legislation and the farmers’ operational structures already in place, such as crop rotation, available application techniques and manure management demands. The aim was to achieve both implementation practicability and acceptance of the study results by the farmers. Results from the year 2020 showed that LAS applied with three-jet nozzles in barley and wheat had significantly lower yields than the other fertilizers. Applied with a slurry tanker trailing shoe applicator in 2021, LAS had comparable yields to the other fertilizers in maize (51.2 t ha −1 ) and comparable yields to digestate in rapeseed (4.4 t ha −1 ). Application techniques that minimize environmental impacts and lower the LAS pH could potentially increase the effectiveness of the fertilizer. We recommend that farmers use this fertilizer not as a single solution but as a mineral compensatory fertilizer in addition to organic fertilizers following local fertilizer legislation. In this case, LAS could potentially substitute calcium ammonium nitrate (CAN).

Calcium nitrate tetrahydrate, used in fertilizers, wastewater treatment, and concrete admixtures, has limited toxicity data despite extensive industrial use. This study evaluated its repeated-dose and reproductive/developmental toxicity in Sprague Dawley rats following OECD TG 422, which combines TG 407 and 421 to extend dosing than TG 407 and reduce animal use compared with separate studies. Rats were administered 0, 100, 300, or 1000 mg/kg/day. Males were treated for 49 days and females from 2 weeks pre-mating to postpartum day 13; the recovery group was observed for an additional 2 weeks. Endpoints included clinical signs, body weight, food consumption, hematology, serum biochemistry, organ weights, histopathology, reproductive performance, and F1 development. No systemic toxicity was observed in F0 males. Minimal prostate atrophy occurred in high-dose males but was considered non-adverse due to limited severity. One high-dose female died on PPD 1, and high-dose F1 litters showed decreased litter size, increased post-implantation loss, and a reduced live-born index. Based on these results, NOAELs were cautiously assigned 1000 mg/kg/day for repeated-dose and male reproductive toxicity and 300 mg/kg/day for female reproductive and developmental toxicity. TG 422 efficiently characterized hazards while reducing animal use, though its limited duration and scope indicate the need for complementary studies.

Ca(NO 3 ) 2 addition has proved to have a high potential to immobilize internal phosphorus (P) in sediments; however, it cannot effectively stop the release of ammonium-nitrogen (NH 4 + -N) from sediments into overlying waters (OL-waters). Additionally, the addition of Ca(NO 3 ) 2 alone has high risk of nitrate-nitrogen (NO 3 − -N) releasing into OL-waters. To overcome the shortcoming of the Ca(NO 3 ) 2 addition method, we reported an integrated method, i.e., a combined method based on Ca(NO 3 ) 2 injection, zeolite capping, and anion exchange resin (AERN)–contained floating system suspending (Ca(NO 3 ) 2 /zeolite/AERN). The effectiveness and mechanism of the Ca(NO 3 ) 2 /zeolite/AERN method for simultaneously controlling the release of soluble reactive P (SRP) and NH 4 + -N were investigated, and the NO 3 − -N releasing risk of this method was evaluated. It was found that the joint use of Ca(NO 3 ) 2 injection, zeolite capping, and AERN-contained floating system suspending not only could effectively suppress the release of SRP and NH 4 + -N from sediments into OL-waters simultaneously, but also had much less risk of NO 3 − -N releasing into OL-waters as compared to the single Ca(NO 3 ) 2 injection method and the combined Ca(NO 3 ) 2 /zeolite method. The inhibition of the reductive dissolution of the P-bound Fe(III) oxides/hydroxides by the presence of nitrate and the adsorption of ammonium on the zeolite played very important roles in the interception of SRP and NH 4 + -N releasing into OL-waters by the Ca(NO 3 ) 2 /zeolite/AERN method. After the sediment remediation using the Ca(NO 3 ) 2 /zeolite/AERN approach, the increase in the content of residual P in the sediment layer of 0–50 mm, the decrease of mobile P in the sediment layer of 0–10 mm, and the increased NH 4 + -N adsorption capacity for the sediment layer of 0–10 mm would be conductive to the interception of SRP and NH 4 + -N liberation in the long run. Results of this research suggest a promising application potential of the Ca(NO 3 ) 2 /zeolite/AERN method in the simultaneous control of the release of SRP and NH 4 + -N from sediments.

Knowing the influence of long-term N fertilization is a key aspect in improving the yield of most crops, including sugarcane ( Saccharum spp.). We aimed to assess the effect of N-fertilizer sources and rates on sugarcane yield, biomass partitioning, juice quality, nutrient accumulation, and N efficiency in acid soils. Two field experiments were carried out in southeastern Brazil for consecutive five years. Six N-fertilizer managements [ammonium nitrate and urea at a rate of 100 kg N ha − 1 (AN100 and UR100, respectively), calcium ammonium nitrate at a rate of 50, 100, 150, and 200 kg N ha − 1 (CAN50, CAN100, CAN150, and CAN200, respectively)] were applied to acidic soils. Nitrogen fertilization did not affect sugarcane and sugar yields at the site with previous rotation with peanut ( Arachis hypogea ) before crop replanting. Conversely, at the site under continuous monoculture, AN100, CAN100, and CAN150 showed increases of 7–25% in sugarcane and sugar yields, and 3–7% in Brix and recoverable total sugar content. We conclude that in responsive sites, fertilizer N additions improve crop yield and juice quality, although high N inputs in the long term (> 100 kg N ha − 1 ) can reduce sugarcane sustainability. Similarly, non-responsive sites can exhibit substantial economic losses and environmental pollution. Identifying responsive and non-responsive sites to fertilizer N is required for improving N use efficiency and reducing environmental risks and economic losses.

Abstract Two randomized block designs were performed to evaluate the effects of bismuth subsalicylate (BSS) and encapsulated calcium-ammonium nitrate (eCAN) on enteric methane production, nutrient digestibility, liver mineral concentration, and performance of beef cattle consuming bahiagrass hay (Paspalum notatum; ad libitum) and sugar cane molasses [1.07 kg/d; dry matter basis]. Experiment 1, used 25 crossbred steers [335 ± 46 kg of initial body weight (BW)] with a 2 × 2 + 1 factorial arrangement of treatments for two 20 d periods. Factors were nonprotein nitrogen (NPN) source (350 mg/kg BW of nitrate or 182 mg/kg BW of urea), BSS (0 or 58.4 mg/kg BW), and a negative control (NCTRL; bahiagrass hay and molasses only). Steers were re-randomized for a second period (n = 10/treatment total). Intake, apparent total tract digestibility and enteric methane were evaluated. Experiment 2 used 75 crossbred heifers in 25 pens (3 heifers/pen; 279 ± 57 kg of initial BW), consuming the same diet and treatments as experiment 1, to determine liver mineral concentration and growth performance over 56 d. Orthogonal contrasts were used to evaluate the effects of NPN (NCTRL vs. others), source of NPN (NS; urea vs. eCAN), BSS, and NS × BSS. For experiment 1, no interactions were observed for any variables, nor were there any effects of NPN on total tract digestibility of nutrients, except for crude protein. Digestibility of all nutrients was reduced (P ≤ 0.021) for steers consuming eCAN compared with urea. There was no effect (P > 0.155) of BSS on digestibility of nutrients; however, BSS reduced (P = 0.003) apparent S retention. Enteric CH4 emission (g/kg BW0.75) was decreased (P = 0.051) by 11% with the addition of eCAN compared with urea. For experiment 2, no NS × BSS interactions (P ≥ 0.251) were observed to affect liver mineral concentration; however, the addition of BSS decreased liver concentration of Cu (P = 0.002) while increasing Fe concentration (P = 0.016). There was an NS × BSS interaction (P = 0.048) where heifers consuming eCAN and BSS had lesser final BW compared with heifers consuming urea and BSS. While eCAN may be a viable resource for mitigating enteric CH4 production of forage-fed cattle, the negative effects on digestibility should be considered. Furthermore, BSS, at the amount provided, appears to have no negative effects on digestibility of nutrients in forage-fed cattle; however, there may be deleterious impacts on performance depending upon what nitrogen source is supplied.