Disodium Citrate Research Articles

Suppression of Zinc Dendrite Growth by Enhanced Polyacrylamide Gel Electrolytes in Zinc-Ion Battery.

Aqueous zinc-ion batteries have become a promising energy storage battery due to high theoretical specific capacity, abundant zinc resources and low cost. However, zinc dendrite growth and hydrogen evolution reaction limit their application. This study aims to improve the cycling performance and stability of aqueous zinc-ion batteries by improving the gel electrolyte. Polyacrylamide (PAM) is selected as the base material of the gel electrolyte, which has good stability and safety, but the water retention capacity, Zn2+ migration number, and ionic conductivity of PAM are low, which affects the long-term stability of the battery. In response to these problems, we optimized PAM by chemical cross-linking method, and formed an enhanced PAM gel by adding disodium citrate dihydrate (SC). Experimental results show that the introduction of an appropriate amount of SC in the enhanced PAM gel electrolyte can significantly improve its electrochemical performance. The zinc-ion symmetric battery achieved a stable cycle of more than 2100 hours at a current density of 0.5 mA cm-2, which is mainly attributed to the inhibitory effect of the enhanced PAM gel on zinc dendrite growth and hydrogen evolution reaction. This study provides a new direction for the development and application of flexible zinc-ion batteries.

Mitigating antimicrobial resistance, an approach to stewardship in canine urinary tract infection.

Urinary tract infection (UTI) caused by antimicrobial resistant bacteria is common in dogs leading to serious health impact in pet animal as well as on human health. Understanding the prevalent uropathogens and their drug susceptibility is essential for limiting the antimicrobial resistance through implementation of stewardship policies. In view of this, present study was envisaged to determine the prevalent bacterial uropathogens and their antibiogram from clinical cases of canine UTI. Urine samples were collected from 35 dogs presented with clinical signs of UTI and a total of 27 bacterial isolates were recovered. Among that Escherichia coli was the most predominant isolate followed by Klebsiella aerogenes, Staphylococcus aureus, Proteus mirabilis, Enterococcus sp. and Citrobacter freundii. All isolates were found resistant to one or more 1st line antibiotics recommended by consensus guidelines and 70% of total isolates showed multidrug resistance. Additionally, this study evaluated the weightage of empirical therapy as per the consensus guidelines over antimicrobial susceptibility test guided treatment. Dogs with uncomplicated UTI were selected and categorized into three different groups (n = 6). Group 1 was treated with common empirical choice amoxycillin-clavulanic acid and dogs showed susceptible to ciprofloxacin were kept in Group 2 and treated with ciprofloxacin along with urinary alkalizer disodium hydrogen citrate. Nitrofurantoin susceptible cases were kept in Group 3 and treated with a combination of nitrofurantoin and urinary acidifier ammonium chloride. Therapeutic outcome was evaluated and success rate was higher in Group 2 and 3 than Group 1 suggested that selection of antibiotics with the use of local or institutional antibiogram data is more considerate than acknowledged international guidelines in the existing situation.

Screening of organophosphorus flame retardant residues in rice by QuEChERS-gas chromatography-quadrupole time-of-flight mass spectrometry

Organophosphorus flame retardants (OPFRs) have emerged as good alternatives to brominated flame retardants, the use of which is globally restricted. In this study, a screening method based on QuEChERS-gas chromatography-quadrupole time-of-flight mass spectrometry (GC-Q-TOF/MS) was established for the determination of 21 OPFRs in rice. First, full scan (scanning range, m/z 50-450) was performed with a mixed standard solution of the 21 OPFRs (0.1 μg/g) by GC-Q-TOF/MS. The fragmentation pathways of these OPFRs were then investigated to explore their cleavage fragments, the interrelationships among fragments, and the possible cleavage modes of alkylated, chlorinated, and aromatic OPFRs. The retention times, isotopic abundance ratios, and molecular formulas of the characteristic fragments as well as the exact mass of the compounds were obtained to establish a mass spectral library of the OPFRs. Rice samples were extracted and purified by the QuEChERS method, and 0.5% formate acetonitrile solution was used as the extraction solvent; 4 g of magnesium sulfate, 1 g of sodium chloride, 0.5 g of disodium hydrogen citrate, and 1 g of sodium citrate as the extraction-salt combination; and 50 mg of primary secondary amine (PSA), 50 mg of octadecylsilane (C18), and 150 mg of magnesium sulfate as the purification materials. The chromatographic separation of the 21 OPFRs was completed within 16 min under optimized temperature program conditions on the DB-5MS UI column. The screening parameters were optimized, and a full scan of the samples was performed under the following conditions: number of characteristic fragment ions ≥2; accurate mass window=±2×10-5 (±20 ppm); retention time deviation=±0.2 min, and ion abundance deviation<20%. The developed method was applied to the screening 21 OPFRs in the samples. The results indicated that the matrix interference was greatly reduced by decreasing the extraction accurate mass window, thereby improving the signal-to-noise ratio of the analytes. The targets were extracted from the matrix interference and background noise using deconvolution software, which improved the match between the target compounds and the mass spectral library. The detection rates of alkyl and aromatic OPFRs increased by 22% and 25%, respectively, when the spiking level was increased from 2 to 10 ng/g. Among the chlorinated OPFRs, only tris(2-chloroisopropyl) phosphate (TCIPP) was not detected at a spiking level of 2 ng/g, indicating that chlorinated OPFRs could be identified even at low concentrations. The characteristic ions of the detected compounds matched those of the home-made mass spectral library well, indicating that the practical application of the home-made mass spectral library. The established screening method was applied in the determination of OPFRs in rice samples from different regions in China. A total of 11 OPFRs were detected, among which trimethyl phosphate (TMP), tri-iso-butyl phosphate (TiBP), and tris(3,5-dimethylphenyl) phosphate (T35DMPP) had the highest detection rates. These results indicate that these three OPFRs are widely used and can easily come into contact with rice samples through various routes. Differences in the types of OPFRs detected in the actual samples may be related to the types of OPFRs produced in local factories. OPFRs can be detected in rice samples by the developed GC-Q-TOF/MS screening method, which is helpful for the identification of OPFRs in complex matrix samples.

Analysis, Occurrence and Exposure Evaluation of Antibiotic and Anthelmintic Residues in Whole Cow Milk from China.

An optimized QuEChERS method for the simultaneous extraction of 26 antibiotics and 19 anthelmintics in whole cow milk was established, followed by UHPLC-MS/MS analysis. Briefly, 20 mL acetonitrile with 1 g disodium hydrogen citrate, 2 g sodium citrate, 4 g anhydrous MgSO4, and 1 g sodium chloride were added to 10 g milk for target chemical extraction, followed by 50 mg anhydrous MgSO4 for purification. Satisfactory recoveries were obtained using the modified QuEChERS method, with recoveries of the antibiotics ranging from 79.7 to 117.2%, with the exception of norfloxacin, which was at 53.4%, while those for anthelmintics were in the range of 73.1-105.1%. The optimized QuEChERS method presented good precision, with relative standard deviations ranging from 7.2 to 18.6% for both antibiotics and anthelmintics. The method was successfully applied to analyze the antibiotics and anthelmintics in 56 whole cow milk samples from China. Briefly, the detection frequencies and concentrations of most of the antibiotics and anthelmintics were low in the whole cow milk samples, with concentrations ranging from below LOD to 4296.8 ng/kg. Fenbendazole, febantel, enrofloxacin, levofloxacin, sulfadiazine, and sulfamethoxazole were the predominant drug residues in the whole cow milk samples. Spatial distribution was found for those antibiotics and anthelmintics with detection frequency higher than 50%, especially for the antibiotics, indicating regional differences in drug application. Based on the current study, exposure to antibiotics and anthelmintics through whole cow milk consumption are lower than the acceptable daily intake values suggested by the China Institute of Veterinary Drug Control. However, long-term exposure to low doses of antibiotics and anthelmintics still needs attention and merits further study.

In vitro evaluation of the virucidal activity of disodium citrate perhydrate (2SCP) disinfectant against SARS-CoV-2

• Virucide activity of disodium citrate perhydrate (2SCP) against SARS-CoV-2.

QuEChERS sample pre-processing with UPLC–MS/MS: A method for detecting 19 quinolone-based veterinary drugs in goat’s milk

We develop and validate a method for the rapid determination and identification of 19 quinolones in goat’s milk by combining the QuEChERS technique with ultra-performance liquid chromatography–tandem mass spectrometry. Plackett–Burman and Central Composite Design methods were used to select the parameters that best promote the extraction efficiency, which led to extraction with acetonitrile/5% formic acid, followed by phase separation with sodium citrate, disodium hydrogen citrate, Na2SO4, and NaCl as optimal. The supernatant was then extracted and cleaned by dispersive solid-phase extraction using C18 and Na2SO4 aided by low-temperature clean-up. The method was validated, with limits of quantification (LOQs) of 5 ppb, specificities of 1/5 LOQ, linearities (R2) > 0.9853, recoveries of 73.4–114.2%, repeatabilities < 15.0%, and intermediate precisions < 13.6%. The developed method was suitable for the routine analysis of quinolone residues in goat’s milk and was used to test 10 goat milk samples produced in Taiwan.

Determination of 118 pesticide residues in dried wolfberry by gas chromatography-triple quadrupole mass spectrometry in dynamic multiple reaction monitoring mode

枸杞中丰富的营养物质深受广大消费者喜爱,但也极易受到病虫侵害,农药残留问题引起了人们的广泛关注。基质干扰是微量分析的一个难点,高灵敏度和高选择性的色谱-串联质谱技术是复杂基质中微量分析强有力的工具,动态扫描监测模式的优越性逐渐取代传统的多反应监测扫描模式,简便、快速、省时的QuEChERS前处理方法已被广泛应用于食品的农药残留检测中。采用改良QuEChERS法结合动态多反应监测模式(dMRM),建立了同时检测枸杞干果中118种农药残留的气相色谱-三重四极杆质谱分析方法。实验比较了不同加水量、提取溶剂、提取过程中温度提取条件,以及无水硫酸镁吸水剂、乙二胺-N-丙基硅烷化硅胶PSA、十八烷基硅烷键合硅胶C18净化填料添加量时农药的回收率,确定出最优前处理方法。结果表明,5 g样品经10 mL超纯水复水,用10 mL乙腈浸提,于-18 ℃冷冻10 min后,用缓冲体系盐包提取后,经800 mg无水硫酸镁、150 mg PSA、150 mg C18混合填料净化,基质匹配外标法定量。118种农药在一定范围内线性关系良好,相关系数R2≥0.9923,检出限和定量限分别为0.006~28.344 μg/kg和0.021~94.480 μg/kg, 4个添加水平的回收率为64.97%~126.21%, RSDs均小于19%(n=6)。基质效应考察结果表明,82%的农药呈现为基质增强效应,其他为基质抑制效应;9%的农药表现为强基质效应,其他为中等或弱基质效应;采用基质匹配标准曲线校正,可有效降低基质效应的影响。应用建立的方法测定10批枸杞样品,全部样品有农药检出,共检出农药22种。该方法操作简便快速,准确可靠,适用于枸杞干果中农药多残留的日常检测和快速筛查。

Comparative study on Labneh cheese made from milk fat and avocado paste

The present study was carried out to prepare a healthy Labneh cheese from fresh whole buffalo's milk and avocado paste en route to innovate a functional food. To achieve the purpose of this research, a pasteurized buffalo’s milk (at 74°C for 15 sec) was cooled immediately to 40°C and divided into four equal quantities. The first quantity was manufactured as a control. The second, third, and fourth quantities were mixed with avocado paste and 0.1% disodium citrate at percentages of 5, 10 and 15%, respectively then stirred well to obtain uniform mixtures. Then a concentration of 4% fresh prepared bacterial yoghurt starter culture was added for all milk portions and incubated at 40 °C. The incubation was terminated at pH 4.8. All treatments were put into cloth bags and hung up in a refrigerator to allow whey to drain for 12 h, then 1% salt was added and filled into suitable containers. The obtained results showed that, the Labneh fortification with avocado paste up to 5% led to improve the body and the texture and did not clearly affect the appearance and the flavor. While the exceeding avocado paste addition to 15% led to a decrease in the degrees of texture, body and appearance. Also it was determined the total cost of one kg Labnehcheesecontaining 5% avocado pasteincreased only by 8.9% versus the control. Finally, the forgoing results led satisfactory to conclude that, it could successfully made a Labneh cheese that meets the intended health purposes based on the fortification with 5% avocado pasteofmany impressive health benefits en route to innovate a functional food.

Comparative study on Labneh cheese made from milk fat and avocado paste

The present study was carried out to prepare a healthy Labneh cheese from fresh whole buffalo's milk and avocado paste en route to innovate a functional food. To achieve the purpose of this research, a pasteurized buffalo’s milk (at 74°C for 15 sec) was cooled immediately to 40°C and divided into four equal quantities. The first quantity was manufactured as a control. The second, third, and fourth quantities were mixed with avocado paste and 0.1% disodium citrate at percentages of 5, 10 and 15%, respectively then stirred well to obtain uniform mixtures. Then a concentration of 4% fresh prepared bacterial yoghurt starter culture was added for all milk portions and incubated at 40 °C. The incubation was terminated at pH 4.8. All treatments were put into cloth bags and hung up in a refrigerator to allow whey to drain for 12 h, then 1% salt was added and filled into suitable containers. The obtained results showed that, the Labneh fortification with avocado paste up to 5% led to improve the body and the texture and did not clearly affect the appearance and the flavor. While the exceeding avocado paste addition to 15% led to a decrease in the degrees of texture, body and appearance. Also it was determined the total cost of one kg Labnehcheesecontaining 5% avocado pasteincreased only by 8.9% versus the control. Finally, the forgoing results led satisfactory to conclude that, it could successfully made a Labneh cheese that meets the intended health purposes based on the fortification with 5% avocado pasteofmany impressive health benefits en route to innovate a functional food.

Clinico-diagnosis and Surgico-therapeutic Management of Lower Urinary Tract Disorders in Dogs

Background: The available literature and work done so far on diagnosis and therapeutic management of lower urinary tract affections in canine practice is very meagre specially on urethro-cystoscopic examinations, medicinal dissolution of calculi and immunotherapy for neoplasia of UB in dogs. Methods: The present study was carried in 55 dogs with lower urinary tract affections classify according to pathological conditions and therapeutic management. The diagnostic modalities like radiography, ultrasonography in all dogs, urethro-cystoscopy in seven dogs and their findings were studied. The response of therapeutics were also studied.Conclusion: The dogs having small size calculi treated according to urine pH with oral medicinal dissolution using Ammonium Chloride (Group 1A, n=9) and Di Sodium Hydrogen Citrate (Group 1B, n=10) for sixty days, Group 1C (n=25) dogs with cystitis (n=17) subjected for bacterial culture treated according to sensitive antibiotics, TCC of bladder (n=7) with immunotherapy using BCG vaccine and a dog with leiomyosarcoma with cystotomy. The dogs (Group 2, n=11) with large size calculi (n=10), a lodge catheter in UB and dogs (Group 3, n=6) did not responded medicinal dissolution from group 1A (n=2) and 1B (n=4) treated surgically. One to multiple, variable size recovered calculi (n=24) revealed highest brown colour grossly, calcium oxalate type, higher in Pomeranian breed and dogs fed with combination of vegetarian and commercial feed.

Structures of disodium hydrogen citrate mono-hydrate, Na2HC6H5O7(H2O), and di-ammonium sodium citrate, (NH4)2NaC6H5O7, from powder diffraction data.

The crystal structures of disodium hydrogen citrate monohydrate, Na2HC6H5O7(H2O), and di-ammonium sodium citrate, (NH4)2NaC6H5O7, have been solved and refined using laboratory X-ray powder diffraction data, and optimized using density functional techniques. In NaHC6H5O7(H2O), the NaO6 coordination polyhedra share edges, forming zigzag layers lying parallel to the bc plane. The hydro-phobic methyl-ene groups occupy the inter-layer spaces. The carb-oxy-lic acid group makes a strong charge-assisted hydrogen bond to the central carboxyl-ate group. The hydroxyl group makes an intra-molecular hydrogen bond to an ionized terminal carboxyl-ate oxygen atom. Each hydrogen atom of the water mol-ecule acts as a donor, to a terminal carboxyl-ate and the hydroxyl group. Both the Na substructure and the hydrogen bonding differ from those of the known phase Na2HC6H5O7(H2O)1.5. In (NH4)2NaC6H5O7, the NaO6 coordination octa-hedra share corners, making double zigzag chains propagating along the b-axis direction. Each hydrogen atom of the ammonium ions acts as a donor in a discrete N-H⋯O hydrogen bond. The hydroxyl group forms an intra-molecular O-H⋯O hydrogen bond to a terminal carboxyl-ate oxygen atom.

Biochemical and anaplerotic applications of in vitro models of propionic acidemia and methylmalonic acidemia using patient-derived primary hepatocytes

Propionic acidemia (PA) and methylmalonic acidemia (MMA) are autosomal recessive disorders of propionyl-CoA (P-CoA) catabolism, which are caused by a deficiency in the enzyme propionyl-CoA carboxylase or the enzyme methylmalonyl-CoA (MM-CoA) mutase, respectively. The functional consequence of PA or MMA is the inability to catabolize P-CoA to MM-CoA or MM-CoA to succinyl-CoA, resulting in the accumulation of P-CoA and other metabolic intermediates, such as propionylcarnitine (C3), 3-hydroxypropionic acid, methylcitric acid (MCA), and methylmalonic acid (only in MMA). P-CoA and its metabolic intermediates, at high concentrations found in PA and MMA, inhibit enzymes in the first steps of the urea cycle as well as enzymes in the tricarboxylic acid (TCA) cycle, causing a reduction in mitochondrial energy production. We previously showed that metabolic defects of PA could be recapitulated using PA patient-derived primary hepatocytes in a novel organotypic system. Here, we sought to investigate whether treatment of normal human primary hepatocytes with propionate would recapitulate some of the biochemical features of PA and MMA in the same platform. We found that high levels of propionate resulted in high levels of intracellular P-CoA in normal hepatocytes. Analysis of TCA cycle intermediates by GC–MS/MS indicated that propionate may inhibit enzymes of the TCA cycle as shown in PA, but is also incorporated in the TCA cycle, which does not occur in PA. To better recapitulate the disease phenotype, we obtained hepatocytes derived from livers of PA and MMA patients. We characterized the PA and MMA donors by measuring key proximal biomarkers, including P-CoA, MM-CoA, as well as clinical biomarkers propionylcarnitine-to-acetylcarnitine ratios (C3/C2), MCA, and methylmalonic acid. Additionally, we used isotopically-labeled amino acids to investigate the contribution of relevant amino acids to production of P-CoA in models of metabolic stability or acute metabolic crisis. As observed clinically, we demonstrated that the isoleucine and valine catabolism pathways are the greatest sources of P-CoA in PA and MMA donor cells and that each donor showed differential sensitivity to isoleucine and valine. We also studied the effects of disodium citrate, an anaplerotic therapy, which resulted in a significant increase in the absolute concentration of TCA cycle intermediates, which is in agreement with the benefit observed clinically. Our human cell-based PA and MMA disease models can inform preclinical drug discovery and development where mouse models of these diseases are inaccurate, particularly in well-described species differences in branched-chain amino acid catabolism.

Pseduocapacitve Properties of CuO/Co3O4 Nanoparticles Synthesized Via Hydrothermal Method

This paper discusses results obtained on CuO/Co3O4 nanoparticles synthesized through simple hydrothermal method with aid of the surfactant (Disodium citrate). The morphology and structure of the samples were examined through SEM, XRD and FTIR studies. Electrochemical investigations of the CuO/Co3O4 samples were studied through CV (cyclic voltammetry), (CHDH) charge- discharge and (EIS) impedance analysis by gel electrolyte. Specific capacitance value of 959 F g-1 at a scan rate of 2 mV s-1 was obtained. From EIS analysis, a low RCT value of 1.06 Ω was attained. Based on the electrochemical performance and ease synthesis method indicate that the prepared electrode (CuO/Co3O4) is suitable candidate for supercapacitor applications.

Validation of ELISA and cellular uptake inhibition assays to detect and quantify antibodies raised against sebelipase alfa in lysosomal acid lipase deficiency

Propionic acidemia (PA) and methylmalonic acidemia (MMA) are autosomal recessive disorders of propionyl-CoA (P-CoA) catabolism, which are caused by a deficiency in the enzyme propionyl-CoA carboxylase or the enzyme methylmalonyl-CoA (MM-CoA) mutase, respectively. The functional consequence of PA or MMA is the inability to catabolize P-CoA to MM-CoA or MM-CoA to succinyl-CoA, resulting in the accumulation of P-CoA and other metabolic intermediates, such as propionylcarnitine (C3), 3-hydroxypropionic acid, methylcitric acid (MCA), and methylmalonic acid (only in MMA). P-CoA and its metabolic intermediates, at high concentrations found in PA and MMA, inhibit enzymes in the first steps of the urea cycle as well as enzymes in the tricarboxylic acid (TCA) cycle, causing a reduction in mitochondrial energy production. We previously showed that metabolic defects of PA could be recapitulated using PA patient-derived primary hepatocytes in a novel organotypic system. Here, we sought to investigate whether treatment of normal human primary hepatocytes with propionate would recapitulate some of the biochemical features of PA and MMA in the same platform. We found that high levels of propionate resulted in high levels of intracellular P-CoA in normal hepatocytes. Analysis of TCA cycle intermediates by GC–MS/MS indicated that propionate may inhibit enzymes of the TCA cycle as shown in PA, but is also incorporated in the TCA cycle, which does not occur in PA. To better recapitulate the disease phenotype, we obtained hepatocytes derived from livers of PA and MMA patients. We characterized the PA and MMA donors by measuring key proximal biomarkers, including P-CoA, MM-CoA, as well as clinical biomarkers propionylcarnitine-to-acetylcarnitine ratios (C3/C2), MCA, and methylmalonic acid. Additionally, we used isotopically-labeled amino acids to investigate the contribution of relevant amino acids to production of P-CoA in models of metabolic stability or acute metabolic crisis. As observed clinically, we demonstrated that the isoleucine and valine catabolism pathways are the greatest sources of P-CoA in PA and MMA donor cells and that each donor showed differential sensitivity to isoleucine and valine. We also studied the effects of disodium citrate, an anaplerotic therapy, which resulted in a significant increase in the absolute concentration of TCA cycle intermediates, which is in agreement with the benefit observed clinically. Our human cell-based PA and MMA disease models can inform preclinical drug discovery and development where mouse models of these diseases are inaccurate, particularly in well-described species differences in branched-chain amino acid catabolism.

Determination of bisultap residue in tropical fruits by ultra performance liquid chromatography-tandem mass spectrometry

A method for the determination of bisultap in tropical fruits was developed by modified QuEChERS method and ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). The tropical fruit samples were twice extracted with acetonitrile containing 1% (v/v) acetic acid, and purified by 200 mg of primary secondary amine (PSA), 100 mg of C18, 300 mg of MgSO4 and 500 mg of disodium hydrogen citrate. The analyte was separated on a CAPCELL CORE PC hydrophilic column, detected in the negative ion multiple reaction monitoring (MRM) mode, and quantified by external standard method. A good linear relationship in the range of 0.1-10.0 μg/L was obtained with the correlation coefficient (r2) of 0.9993. The limit of detection and limit of quantification were 0.015 μg/kg and 0.05 μg/kg, respectively. The spiked recoveries were in the range of 81.0%-88.3% with the relative standard deviations from 3.9% to 6.2%. The method has good purification effect and high sensitivity, and is suitable for the rapid analysis of the bisultap residues in tropical fruits.

Disodium citrate-assisted hydrothermal synthesis of V2O5 nanowires for high performance supercapacitors.

Orthorhombic vanadium pentoxide (V2O5) nanowires with uniform morphology were successfully fabricated via a facile hydrothermal process. The effect of disodium citrate dosage on the crystallinity, morphology and electrochemical properties of the products was analyzed. Experimental results indicate that orthorhombic V2O5 nanowires with high crystallinity and diameter of about 20 nm can be obtained at 180 °C for 24 h when the dosage of disodium citrate is 0.236 g. Furthermore, the prepared V2O5 nanowires demonstrate a high specific capacitance of 528.2 F g−1 at 0.5 A g−1 and capacitance retention of 85% after 1000 galvanostatic charge/discharge cycles at 1 A g−1 when used as supercapacitors electrode in 0.5 M K2SO4.

Disodium hydrogen citrate sesquihydrate, Na2HC6H5O7(H2O)1.5.

The crystal structure of disodium hydrogen citrate sesquihydrate, 2Na2 (+)·C6H6O7 (2-)·1.5H2O, has been solved and refined using laboratory X-ray single-crystal diffraction data, and optimized using density functional techniques. The asymmetric unit contains two independent hydrogen citrate anions, four sodium cations and three water molecules. The coordination polyhedra of the cations (three with a coordination number of six, one with seven) share edges to form isolated 8-rings. The un-ionized terminal carb-oxy-lic acid groups form very strong hydrogen bonds to non-coordinating O atoms, with O⋯O distances of 2.46 Å.

The effect of temperature and molar mass on the (liquid + liquid) equilibria of (poly ethylene glycol dimethyl ether + di-sodium hydrogen citrate + water) systems: Experimental and correlation

The (liquid+liquid) equilibrium for the {polyethylene glycol dimethyl ether 2000 (PEGDME2000)+di-sodium hydrogen citrate+H2O} system was studied at T=(298.15, 308.15 and 318.15)K and atmospheric pressure (≈85kPa). The free energies, enthalpies and entropies of cloud points were calculated in order to investigate the driving force formation of this two-phase system. To investigate the effect of molar mass of the polymer on the binodals and tie-lines, similar measurements were also made at T=298.15K on this two-phase system consisting of the PEGDME with molar masses of 500 and 250g⋅mol−1. The effective excluded volume model was used for representation of the phase-forming ability in PEGDME systems. An empirical and the Merchuck equations with the temperature dependency were used to correlate the binodal curves. The Othmer–Tobias and Bancraft and Setschenow equations, the osmotic virial and the extended NRTL models were used to fit the tie-line data.

Investigations of the interactions in aqueous poly (vinyl pyrrolidone) + di-sodium hydrogen citrate solutions using vapor–liquid equilibria studies at different temperatures

Vapor–liquid equilibrium data of binary aqueous di-sodium hydrogen citrate (Na2HCit) aqueous poly (vinyl pyrrolidone), and ternary aqueous (Na2HCit)+poly (vinyl pyrrolidone) solutions were measured using the isopiestic method at T=(298.15, 308.15, 318.15) K. The obtained vapor–liquid equilibria data for binary aqueous di-sodium citrate system were successfully fitted with the Pitzer equation. From these data, the corresponding activity coefficients have been calculated. Using the general Pitzer formalism an equation was employed to correlate the obtained osmotic coefficient values for the ternary system. The thermodynamic behavior of aqueous (Na2HCit)+poly (vinyl pyrrolidone) solutions was discussed on basis of water, polymer and salt interactions.

Rapid Chemical Bath Depositions and Properties of SnS Films

Tin sulfide films were deposited from an aqueous solution of tin dichloride, thiacetamide, and disodium citrate. X-ray diffraction, atomic force microscopy, ultraviolet–visible spectrophotometry, and electrical measurement were used to characterize the films. The films directly deposited at 70 and 80 °C for 1 and 2 h showed thicknesses of 70–400 and 120–650 nm, respectively. But the deposition at 40 °C for 1 h (nucleation step) made the films subsequently deposited at 60–80 °C denser and thicker (∼1600–7500 nm) than directly deposited films. Average transmittances of the films in UV–visible range decrease with increase in the thickness and are only in range of 0.33–2.3% for the films deposited with the nucleation step. The band gap energies of the films estimated from the transmittance spectra are in the range of ∼1.37–1.55 eV. Moreover, the films are p-type conductive. The electrical resistance and carrier mobility are in the ranges of 0.3–1.4 × 105 Ω cm and 0.77–1.56 cm2 (V s)−1, respectively. The films deposited with the nucleation step show lower resistance and higher carrier mobility than those deposited without nucleation because of their denser film microstructure and larger film thickness.