Precipitation of Sugammadex With Nicardipine And Labetalol

BackgroundThere is a paucity of clinical data about whether sugammadex forms precipitates with other medications. This laboratory experimental study was performed to determine the drugs that produce precipitate with sugammadex. MethodsSamples of 1 mL of sugammadex were prepared in transparent cylinders, to which 1 mL of test drugs (rocuronium, neostigmine, glycopyrrolate, atropine, nitroglycerin, dobutamine, dopamine, epinephrine, vasopressin, norepinephrine, phenylephrine, ephedrine, esmolol, nicardipine, labetalol) was then added. The precipitation reaction was observed by eyes and light microscope. The pH of each drugs before and after mixing with sugammadex was measured. ResultsWhite crystals were formed when sugammadex mixed with nicardipine or labetalol. ConclusionsSugammadex formed precipitate when mixed with nicardipine or labetalol. Sufficient fluid flushing is required between injections of each drug to prevent these reactions.

An Experimental Study of the Influence of the Preflush Salinity on Enhanced Oil Recovery Using Silica-Based Nanofluids

The underlying effect of preflush salinity and silica nanofluid (Si-NF) on oil production is examined. The influence of salinity on the stability of Si-NFs is studied. A series of sand-pack floodings evaluating oil production was conducted at different concentrations of preflush salinity (0 to 4 wt.%), followed by the injection of a Si-NF (0.5 wt.%) at the trail of which postflush water was injected. The effluent water and solids were collected and analyzed using X-ray fluorescence (XRF). Interfacial tension (IFT) and contact angle measurements were conducted on the Si-NF in the presence of salinity to confirm the effect. The Si-NF became unstable and formed precipitate in the presence of salinity. The sand-pack flooding showed that when the preflush salinity was increased, the displacement efficiency (ED) using the Si-NF and postflush injection was increased (ED = 44%). The XRF of the precipitated effluent revealed that the preflush salinity and Si-NF caused mineral leaching, which triggered pore clogging. The IFT value reduced from 13.3 to 8.2 mN/m, and the wettability was altered to be more strongly water-wet when the salinity increased. The primary mechanisms of oil recovery using the Si-NF after preflush salinity is attributed mainly to the clogging mechanism. This clogging helps block the high-perm area, shift the fluid flow to the oil-trapped zone, and free the oil out. Other contribution mechanisms are IFT reduction and wettability alteration.

Synthesis and Characterization of Mesoporous β-Tricalcium Phosphate

Reconstruction of bone defect due to a disease or a trauma can use autograft, allograft, xenograft or synthetic bonegraft as the bone substitute material. However, in particular cases, it is required a material that has a specific resorption characteristic, beside owning excellent bioactive properties, such as β-tricalcium phosphate (β-TCP). In this study, we report the synthesis of β-TCP particles with mesopores structure by using chitosan and aloe vera as templates. A solution of (NH4)2HPO4 was added dropwise into solution of Ca(NO3)2·4H2O and the template at 85°C for 2 hours, and subsequently aged for 3 hours. Then, the formed precipitate was washed and centrifuged repeatedly prior to drying at 80°C for 24 hours. Finally, the dried precipitate was calcined at 900°C for 1 hour to obtain β-TCP powder. Phase identification and mesopores structure were analyzed using X-ray diffraction (XRD), while the existence of functional groups was identified by Fourier-transform infrared (FTIR) spectroscopy. Microstructure and particle size distribution were characterized by scanning electron microscopy (SEM) and particle size analyzer (PSA), respectively. XRD analysis shows that β-TCP is dominant with the presence of small amount of impurities. Furthermore, low angle peak in XRD analysis indicates the formation of mesopores structure. From the SEM and PSA analysis, the morphology of both TCP-K and TCP-KA particles showed more large agglomerates and more heterogeneous particle size distribution due to the addition of the biopolymers in the synthesis of β-TCP.

The phase formation processes into a short-circuited galvanic couple iron (St3)-carbon (coke) system in water medium

The monograph presents the results of an experimental study of the galvanic coagulation phase formation process in the system of short-circuited galvanic contacts iron - carbon (coke) that was carried out on the current model of industrial galvanocoagulator, water permeability and model solutions of inorganic salts hydroxide structures in situ. The influence of the galvanocoagulation parameters on the phase composition and mass of the formed precipitate, the value of the hydrogen index and the chemical composition of the dispersion medium are established. The conditions of the galvanic contact system transition to the steady state are discovered and the influence of the operating time of the iron component on the chemical and phase composition of the formed pulp is determined. Physicochemical and colloid-chemical mechanisms of phase formation in the system of short-circuited galvanic pair steel-3 - coke are revealed. The separation possibility of dispersed products of galvanic coagulation process by adaptation of traditional methods of natural raw materials separation is shown. Examples of electrolysis, galvanocoagulation and cementation in technological schemes of liquid waste disposal of galvanic productions are given it the monograph.

Corrective Maintenance and Hardening of Agricultural Machinery Parts

The article presents information on the technological characteristics and industrial use of chroming electrolytes. The modern electrochemical technologies of repairing worn-out parts of agricultural machinery are considered. Particular attention is paid to the use of chrome plating methods making possible to increase the durability and reliability of the parts recovered in electrolytes of different composition, allowing to obtain coatings with high physical-mechanical properties that determine their suitability for the operation in the process of use for their intended purpose. The use of self-regulating dilute chroming electrolytes makes possible to increase the productivity of the deposition process of chromium coatings significantly, to obtain high-quality coatings of chromium and iron, and high adhesion to the base material - carbon, alloyed steels, and cast iron. The deposition of metals using reverse, pulsed currents with adjustable anodic-cathodic ratio of amplitude values and its duration allows to influence electro crystallization, control the structure, texture and roughness of the formed precipitate, which makes possible to get with predetermined functional physical and mechanical properties for specific repair conditions and subsequent operation in agricultural machinery. The following modes are recommended for brilliant coatings: when reverse current τ (cat) / τ (an) = 50-70, τ (cat) = 4-7 min, D(cat) = 40-100 А / dm2, D(cat) / D(an) = 3-4, Т = 60-65 ° С; when impulse current D(cat) = 40-100 А / dm2, Т = 60-65 ° С, τ (imp) = 1.5-2.5 min, τ (pauses) = 5-10 sec., impulse ratio 1.07-1.15.

Magnetic and Microwave Absorbing of Mn(1-x)NdxFe2O4 Synthesized with Co-Precipitation Method

Characterization of magnetic and microwave absorbing properties of Mn(1-x)NdxFe2O4 synthesized with co-precipitation method have been carried out. Mn(1-x)NdxFe2O4 (with x = 0.0; 0.4; and 0.8) powders was synthesized from mixture of NiCl2, NdCl3 and FeCl3 in mole ratio. Mixing of this powders were soluted with NH4OH 4M up to pH = 9.0. The formed precipitate were washed with demineralized water up to pH = 7.0 and then dryed at 120 oC for 5 h, sintered at 1200 for 3 h. Phase identification with X-ray diffractometer (XRD) have formed composite multiphases, which indicated by the appearance of MnFe2O4, NdFeO3 and Fe2O3 phase. The magnetic measurement using VSM (vibrating sample magnetometer) showed that the sample exhibited a ferromagnetic behavior, the Ms value is lower (in the range of 30 – 11 emu/g) while the Hc value is greater (in the range of 111 – 132 Oe) with increased concentration of Nd3+ ion (x values). Measurement by VNA (Vector Network Analyzer) showed the ability of absorption of microwaves increased with increasing content of Nd3+ ion, the composition of x = 0.0 at about 70% and addition of Nd3+ ion up to composition x = 0.8 at about 91%. Keywords: MnNd ferrite, co-precipitation methode, magnetic properties, microwave absorption

Study on Radioactive Wastewater Treatment by Precipitation and Membrane Separation

The chemical precipitation method was combined with the membrane separation to treat the simulated radioactive wastewater containing strontium in the paper. The calcium carbonate powder was used to prepare the seed and the sodium carbonate was selected as the precipitant. Sr2+ and CO32- constantly crystallized on the seed surface in the granulation reactor. FeCl3 was dosed in the subsequent membrane separator. The average concentrations of strontium in the raw water and in the effluent were 5.046 mg/L and 0.028 mg/L, respectively. The DF increased gradually with the operation time, with an average value of 279. After the test, the formed precipitate was easy to separate from the liquid and was directly discharge after sedimentation for 24 h. The CF was 3170. The membrane specific flux decreased rapidly in the early stage and then declined slowly with the operation time.

Development and Validation of Spectrophotometric, Atomic Absorption and Kinetic Methods for Determination of Moxifloxacin Hydrochloride

Three simple spectrophotometric and atomic absorption spectrometric methods are developed and validated for the determination of moxifloxacin HCl in pure form and in pharmaceutical formulations. Method (A) is a kinetic method based on the oxidation of moxifloxacin HCl by Fe3+ ion in the presence of 1,10 o-phenanthroline (o-phen). Method (B) describes spectrophotometric procedures for determination of moxifloxacin HCl based on its ability to reduce Fe (III) to Fe (II), which was rapidly converted to the corresponding stable coloured complex after reacting with 2,2’ bipyridyl (bipy). The formation of the tris-complex formed in both methods (A) and (B) were carefully studied and their absorbance were measured at 510 and 520 nm respectively. Method (C) is based on the formation of ion- pair associated between the drug and bismuth (III) tetraiodide in acidic medium to form orange—red ion- pair associates. This associate can be quantitatively determined by three different procedures. The formed precipitate is either filtered off, dissolved in acetone and quantified spectrophotometrically at 462 nm (Procedure 1), or decomposed by hydrochloric acid, and the bismuth content is determined by direct atomic absorption spectrometric (Procedure 2). Also the residual unreacted metal complex in the filtrate is determined through its metal content using indirect atomic absorption spectrometric technique (Procedure 3). All the proposed methods were validated according to the International Conference on Harmonization (ICH) guidelines, the three proposed methods permit the determination of moxifloxacin HCl in the range of (0.8-6, 0.8-4) for methods A and B, (16-96, 16-96 and 16-72) for procedures 1-3 in method C. The limits of detection and quantitation were calculated, the precision of the methods were satisfactory; the values of relative standard deviations did not exceed 2%. The proposed methods were successfully applied to determine the drug in its pharmaceutical formulations without interference from the common excipients. The results obtained by the proposed methods were comparable with those obtained by the reference method.

Calcium sulphate scaling in membrane distillation process

Formation of precipitates containing CaSO4 during membrane distillation, applied to the concentration of aqueous salt solutions, is discussed in this paper. It was found that the concentration of SO42− ions in such solutions should not exceed 600 mg L−1 when they are subjected to concentration. However, concentration of sulphates at the level of 800 mg L−1 in the feed is permissible provided that the excess of CaSO4 is removed in a crystallizer. Crystallisation of salts, mainly CaSO4 · 2H2O, on the surface and inside the membrane was observed at higher feed concentrations, causing damage of the module. Precipitation of calcium sulphate was also observed during the production of demineralised water when high values of the water recovery coefficient (above 90 %) were used. In this case, the formed precipitate also contained CaCO3, the co-precipitation of which significantly changed the properties of the scaling layer. The precipitate containing both CaSO4 and CaCO3 was formed mainly on the membrane surface and it could easily be removed by rinsing the module with a HCl solution.

TEM Studies on the Effect of Nature of Precipitates in Al-Li Alloy on Microstructural Evolution during Severe Plastic Deformation

Equal channel angular extrusion (ECAE), involving intense plastic straining under high applied pressure is generally recognized and extensively studied top down approach for producing bulk ultra-fine grained (UFG) metallic materials, and even going down in size to the nanometer range. In this research efforts are made to identify conditional under which grains with size less than 100 nm form after ECAE. Evolution of microstructure of Al-Li based alloy processed by ECAE is analyzed using transmission electron microscopy (TEM). Observations on the effect of precipitates/second phase particles in the sample on the deformation characteristics and their role on the increased degree of grain fragmentation process is highlighted. Samples of Al-Li based alloy are solutionized, quenched and aged at different temperatures to obtain well formed precipitate laths/plates before subjecting to ECAE. During the deformation process these precipitates disintegrate into fragments and get dispersed into the Al matrix. The fragments of a few nanometers size bring about drastic changes in the flow as well as the recovery characteristics of processed samples. Evidence for dynamic recrystallisation taking place during the ECAE processing is presented. It was observed that optimal thermal treatment leads to more effective grain refinement and consequently an ultra-fine grained microstructure could be achieved even after single pass in Al-Li based alloy containing precipitates and second phase particles.