Min Of Shaking Research Articles

Green and simple approach for flotation, preconcentration and enhanced spectrophotometric assessment of Ni(II) in aqueous solution by complexation with 1-(3,5-dihydroxybenzylidene)thiosemicarbazone

In the current work, 1-(3,5-dihydroxybenzylidene)thiosemicarbazone (H3L) was produced under mechanochemical ball milling conditions using para-toluenesulfonic acid (p-TSA) as a catalyst in a solvent-free reaction. The generated material was characterized using a number of physical and spectroscopic methods. The synthetic material was also tested as an effective organic chelating agent in the flotation, preconcentration, and spectrophotometric measurement of Ni(II) in aqueous solutions, where H3L reacted with Ni(II) to produce a coffee colored complex. Oleic acid (HOL) was used as a foaming agent to help the complex that was generated float to the scum layer. The concentration of Ni(II) was assessed using a spectrophotometer at 370 nm. The several factors that impact the flotation-separation process were evaluated and adjusted, including pH, the concentration of (Ni(II), H3L, and HOL), surfactant type, sample volume, temperature, shaking duration, and ionic strength. Nearly 100% of Ni(II)-H3L were successfully separated at 25 °C and pH 5 after 5 min of shaking. Utilizing the molar ratio approach, the stoichiometric ratio of the produced complex was determined to be (1:2) of M:L. The formation constant (Kf) was determined as 2.25 × 104. The analytical characteristics of the procedure (limit of detection, limit of quantification, and range of linearity) were evaluated and found to be (0.22 ng/mL, 0.74 ng/mL, and 5–400 ng/mL), respectively. The suggested method was employed to separate Ni(II) that had been spiked into some real water samples. Ni(II) was successfully preconcentrated from different aqueous volumes with a preconcentration factor of 200. Finally, the mechanism for the flotation-separation process was suggested.

Error on the Estimation of Sand Size Parameters When Using Small Diameter Sieves and a Solution

Analyses were carried out to determine the main sand size parameters (median grain size D50 and sorting σ) for beach nourishment purposes using the sieving method aboard a dredger. Due to a lack of space and the need to carry and use the material with ease, the sieves are commonly small (10 cm diameter), and the shaking procedure is usually performed by hand. However, the influence of shaking, either mechanically or manually, has not yet been studied with 10 cm diameter sieves. Therefore, 20 samples were taken from inside the hopper of a trailing suction dredger and sieved both manually and mechanically for 10 min. The results showed that manual sieving yielded higher D50 values than the mechanical procedure. The average error arising from using the manual method was 14%, but it can reach 36.5%. The granulometric analysis carried out for different shaking times has shown that this error is < 5% when at least 20 min of shaking is performed. The mechanical procedure gave always finer sand results. In addition, the overfill ratio calculated for both mechanical and manual results reached differences of up to 48%.

Selective Release of Doxorubicin from Cucurbit[8]uril Stabilized Gold Supra-Pyramid Host at pH of Small Intestine.

Gold supra-pyramid structures were obtained by the addition of acidic solution of cucurbit[8]uril (CB[8]) to an aqueous solution of citrate stabilized gold nanoparticles (AuNP). The reaction resulted in the precipitation of supra-pyramid from the solution after just 1 min of shaking. Microscopic images confirmed formation of the supra-pyramid. The stepwise structural transformation towards the supra-pyramid was examined with variable concentrations of CB[8] to AuNP solution. Anionic counter parts of these acids (Br- , NO3 - , SO4 2- and Cl- ) controlled the size of the synthesized supra-pyramids. These supra-pyramid hosts showed uptake of three anticancer drugs: oral drugs etoposide, prednisolone and intravenous drug doxorubicin. Releases of drugs from these hosts were emulated at acidic stomach pH, basic small intestinal pH and in the presence of human serum albumin (HSA). The specific release of doxorubicin was confirmed at small intestinal pH 7.4. Poor release of drugs in presence of CB[8] specific guest 1-adamantanamine confirmed the role of the supra-pyramid as the exclusive host. The release of doxorubicin from the supra-pyramid at pH 7.4 was confirmed by fluorescence microscopic imaging with prostate cancer DU-145 cell line.

Confining SnS2 Ultrathin Nanosheets in Hollow Carbon Nanostructures for Efficient Capacitive Sodium Storage

Summary Tin disulfide (SnS 2 ) is a promising anode material for sodium-ion batteries because of its high specific capacity. However, the low conductivity and large volume change during reaction with Na + ions greatly limit its practical application. Herein, a multistep templating method has been exploited for the rational design and synthesis of SnS 2 nanosheets confined in carbon nanotubes (SnS 2 @CNTs). To demonstrate the universality of this method, SnS 2 nanosheets confined in carbon nanoboxes (SnS 2 @CNBs) and hollow carbon nanospheres (SnS 2 @CNSs) have also been synthesized by simply changing the template in the reaction system. Due to their unique structural merits, the SnS 2 @CNTs, SnS 2 @CNBs, and SnS 2 @CNSs show improved sodium storage performance in terms of high specific capacity, good cycling stability, and superior rate capability.

Oil recovery from wet Euglena gracilis by shaking with liquefied dimethyl ether

An efficient, safe, and low-cost method for recovering oil from microalgae is needed for the production of algae biofuels. Here, we report a one-step method for the recovery of oil from algae. Wet Euglena gracilis cells were placed in a vessel, mixed with liquefied dimethyl ether, and shaken at room temperature (20°C). After 5min of shaking, approximately 96.7% of the total oil was recovered when the ratio of solvent to sample (wet basis) was 8:1. The molecular weight distribution of oil recovered using this method was comparable to that of oil recovered using the conventional n-hexane Soxhlet extraction method. These results showed that it is possible to produce oil from wet microalgae by using a simple, economical, and environmentally friendly method.

The effects of seed traits and fabric type on the retention of seed on different types of clothing

People can intentionally or unintentionally transport seed of a diversity of species over long distances, facilitating plant invasions. To better understand factors affecting unintentional human-mediated seed dispersal, we quantified the effects of seed traits and fabric type on the retention potential of weed seed on clothing. First, we compared seed retention among 33 species of weeds that differ in seed morphology using three fabrics. We then compared seed retention for 10 different fabrics using seed from five species of weeds. Retention potential, calculated as the percentage seed retained on fabric after shaking for fixed periods of time, was compared using Linear Mixed Models. Across the 33 species, seed of most species fell off fabric soon after shaking commenced: 17 species had low retention potentials (<20% of the seed remain attached after 5min of shaking), 10 species had moderate seed retention (20–50% seed retained), and only five species had high retention potentials (>50% seed retained). Retention potentials varied among fabrics, with seed more tightly attaching to fabrics with “woolly” or “fleecy” characteristics such as fleece, knitted wool, double weave wool nylon blend (hiking socks) and ribbed cotton/nylon (sports socks), than to smoother fabrics such as canvas, fine nylon weave, denim and drill cotton. The weight, length and presence of attachment structures affected how long seed remain attached. The effect of these traits varied among fabrics. Seed with structures such as hairs, awns and pappus remained attached for longer on fabrics like fleece and wool, but not on smoother fabrics. These results support the observation that people wearing clothing made of different fabrics are likely to disperse different combinations of weed seed, depending, at least in part, on seed traits. Unintentional human mediated seed dispersal via clothing is therefore a very selective example of epizoochory favouring some weeds more than others.

Seismic performance of reinforced soil wall with untreated and cement-treated soils as backfill using a 1-g shaking table

Reinforced soil walls were only slightly damaged in the recent earthquake disasters in Japan. However, because sandy soils are generally used as backfill in steel-strip reinforced soil walls, these walls may deform during or immediately after an earthquake. Therefore, it is important to clarify the resistance of this type of wall to seismic shocks and to improve the wall׳s seismic performance for stabilisation through such methods as cement treatment. For this purpose, we developed a reinforced soil wall model to simulate the stress and deformation around an embedded reinforcement. The reinforcement used here was a steel strip with ribs. First, a series of conventional pullout tests was performed to examine the pullout resistance of the strip with its ribs embedded in the soil layer. Next, shaking table tests were performed using a reinforced soil wall model with different initial pullout loads applied to the strip. The conditions of the horizontal shaking table tests briefly consisted of a maximum acceleration of 1000Gal and a frequency of 3Hz. The initial pullout load before the shaking tests was set at 75% of the maximum load obtained from the pullout tests. Sand, clay, and cement-treated sand and clay were used for the soil samples. The clay had a fine fraction content of over 25%. This paper discusses the seismic behaviour of a reinforced soil wall composed of sand, clay, and cement-treated clay based on the results of pullout and shaking table tests. The primary conclusions can be summarised as follows: 1) When no overburden pressure was applied, shaking caused the strip in the untreated sand layer to slip within a couple of seconds. Conversely, when the overburden pressure was above 50kPa, the strip did not slip at all during 3min of shaking. When the initial pullout load was decreased by 5%, the facing wall moved forward by only 0.2% of its height. Therefore, no large deformations affecting the instability of the wall were recognised during the shaking tests. 2) Furthermore, in the case of untreated clay with or without overburden pressure, the resistance between the strip and the soil was negligible, and the strip was simultaneously made to slip from the shaking table tests to the same extent as the untreated sand without overburden pressure. 3) After the cement treatment was applied to the clay, the strip did not slip during 3min of shaking, the initial pullout load did not decrease, and the facing wall did not move during the shaking period. 4) When the strip was connected to the facing wall, the strip slipped more slowly than when it was not connected. 5) The stability and seismic performance of the reinforced soil wall were not affected by the ratio of the initial pullout load to the maximum pullout load within the tested range. 6) Conversely, when the acceleration was set to 1500Gal, the initial pullout load decreased by only a maximum of 5%. Therefore, the use of cement-treated soil can crucially improve the stability of a reinforced soil wall, even if a large acceleration occurs during an earthquake.

Influence of the shaking time on the forensic analysis of FTIR and Raman spectra of spray paints

In order to decide if replicated measurements of a trace fall within the intra-variability expected for reference paint samples, a forensic scientist has to understand and integrate all reasonable sources of variation. The origins of such variation in spectra can be various, but mainly include differences in components distribution (homogeneity of spraying) or differences originating from the manufacturing process (production batches). Instrumental variation can also be problematic for non-successive measurements.Infrared and Raman spectra were collected to study the homogeneity of the paint distribution after shaking a spray can for times of 0, 1, 2, 3, 4 and 5min. The results confirm that differences arise in both the spectroscopic techniques used in this study. Mainly, this survey shows that the problematic of shaking is particularly important when the pigment content can be detected from spray paint samples within the infrared domain. In these situations, the signal from the pigment might produce strong absorptions that vary with shaking time, leading to differences in relative intensities with respect to those attributed to the binder. For Raman spectroscopy, it has been shown that a gradient of pigment concentration is observable in some samples depending on the shaking time. The proportion of the signal due to the pigment increases with shaking times from 0 to 1min and diminishes afterwards, to finally reach stabilization around 3min of shaking. Not all samples are affected by these differences and it should always be evaluated on a case-by-case basis. From a statistical point-of-view, principal component analyses of the replicates show that the spectra are reproducible after 3min of shaking.

Colloid Release From Differently Managed Loess Soil

The content of water-dispersible colloids (WDC) in a soil can have a major impact on soil functions, such as permeability to water and air, and on soil strength, which can impair soil fertility and workability. In addition, the content of WDC in the soil may increase the risk of nutrient loss and of colloid-facilitated transport of strongly sorbing compounds. In the present study, soils from the Bad Lauchstädt long-term static fertilizer experiment with different management histories were investigated to relate basic soil properties to the content of WDC, the content of water-stable aggregates (WSA), and aggregate tensile strength. Our studies were carried out on soils on identical parent material under controlled management conditions, enabling us to study the long-term effects on soil physical properties with few explanatory variables in play. The content of WDC and the amount of WSA were measured at a series of time steps giving a colloid release and aggregate disaggregation rate and a quantification of the content of WDC and WSA at a given time for each of the six investigated experimental field plots. The content of WDC in the moist soil was linearly correlated (r = 0.82* [P < 0.05]) to the part of the total clay not associated with organic matter. No significant difference in release rate was found for air-dry aggregates. The low-carbon soils initially had a higher content of WSA but were more susceptible to disaggregation than the high-carbon soils. Furthermore, the application of NPK fertilizer had a destabilizing effect on the WSA and also caused a decrease in the cation exchange capacity of the soils. The mean tensile strength was positively correlated to the colloid release rate and the content of WDC after 2 min of shaking and therefore to the amount of clay not associated with organic carbon.

Synergistic liquid–liquid extractive spectrophotometric determination of gold(III) using 1-(2′,4′-dinitro aminophenyl)-4,4,6-trimethyl-1,4-dihydropyrimidine-2-thiol

Synergistic liquid-liquid extractive spectrophotometric determination of gold(III) using 1-(2',4'-dinitro aminophenyl)-4,4,6-trimethyl-1,4-dihydro pyrimidine-2-thiol [2',4'-dinitro APTPT] has been described. Equal volumes (5cm(3)) of the 2',4'-dinitro APTPT (0.02molL(-1)) in the presence of pyridine (0.5molL(-1)) form an orange-red coloured ternary complex with gold(III) of molar ratio 1:1:1 at pH 1.8-2.4 with 5min of shaking. The absorbance of coloured organic layer in 1,2-dichloroethane is measured spectrophotometrically at 445nm against reagent blank. A pronounced synergism has been observed by the binary mixture of 2',4'-dinitro APTPT and pyridine, which shows that the enhancement in the absorbance is observed in the presence of pyridine by the adduct formation in the organic phase. Beer's law was obeyed in the concentration range 2.5-20.0microgmL(-1), with molar absorptivity and Sandell's sensitivity values of 8.7x10(3)dm(3)mol(-1)cm(-1) and 0.023microgcm(-2) respectively. A repetition of the method was checked by finding relative standard deviation (R.S.D.) (n=10) which was 0.17%. The composition of the gold(III)-2',4'-dinitro APTPT-pyridine adduct was established by slope analysis, molar ratio and Job's method. The ternary complex was stable for more than 48h. The influence of various factors such as pH, 2',4'-dinitro APTPT concentration, solvent and pyridine on the degree of complexation has been established. A number of foreign ions tested for their interferences and use of suitable masking agents wherever necessary are tabulated, which show that selectivity of the method has been enhanced. The method is successfully employed for the determination of gold(III) in binary, synthetic mixtures and ayurvedic samples. The reliability of the method is assured by inter-comparison of experimental values, using an atomic absorption spectrometer.

Deflouridation of water using amended clay

Excessive presence of fluoride (F) in potable water continues to be a serious public health problem in many parts of the world. Hence, the need for a cost effective, simple and user-friendly method for water defluoridation is being felt in such areas. Clay vessels are commonly used in rural parts of India and other developing countries, not only for storing water, but also to get cold potable water during summers. The present study investigates the role of vessels made from locally derived sample of silty clay (C) in water defluoridation. Besides, F sorption by C and its chemically amended forms were also studied to investigate improvement opportunities of clay vessels with regard to their application in water defluoridation. The study revealed C to be a potent F binder and amending it with Al (activated Al 2O 3), Fe (FeCl 3) and/or Ca (CaCO 3) significantly improved its F sorption capacity. F sorption by C amended with Al, Fe or Ca, decreased in the same order. C amended simultaneously with 50 mg/g each of Al, Fe and Ca proved to be the most effective F sorbent at pH≈6. F sorption by amended C followed a rapid kinetics with considerable F being removed within 5 min of shaking. The pilot study employing clay vessels to achieve defluoridation of water exhibited encouraging results suggesting the viability of using chemically amended clay vessels for water defluoridation.

Indirect determination of micrograms of sulfate by barium absorption spectroscopy

Abstract The indirect procedure for sulfate determination by Ba absorption spectroscopy was modified so that low concentrations of SO4 in small volumes of solutions could be determined rapidly and precisely. Major modifications consisted of seeding the sample with BaSO4, precipitating in ethanol solutions to lower BaSO4 solubility, and determining Ba in a N2O‐acetylene flame using the absorption mode. The results showed: complete SO4 precipitation as BaSO4 after 15 min of shaking, little or no effect from solution Al on SO4 determination, quantitative recovery of SO4 from 0.01 M Ca(H2PO4)2 soil extracts, and greater precision of SO4 measurement with indirect method than with turbidimetric method.