Range Of Recovery Rates Research Articles

Headspace-Gas Chromatography Method for Determination of Formaldehyde Content in Wastewater

Through the use of headspace-gas chromatography, the sensitivity and detection limit of formaldehyde content in wastewater obtained by the standard curve method and the standard addition method are compared in order to obtain the best detection method. The results show that the calibration curve correlation of the standard insertion method for testing the formaldehyde content in wastewater is 0.9991, the detection limit of the method is 0.18 mg/L, and the lower limit of determination is 0.69 mg/L. Excellent standard curve method; this method is used for samples with low, medium and high concentrations. The range of standard recovery rate calculated is 85.1%~112.9%, the relative standard deviation in the laboratory is 2.7%~ 6.3%, which is also better than the standard curve method and meets the test requirements. This method is easy to operate, high sensitivity, and low detection limit for the determination of formaldehyde in wastewater, which meets the requirements of analysis and testing.

Determination of sulfur compounds in biological desulfurization system by high performance liquid chromatography

Biological desulfurization is a process in which sulfur compounds are removed from gas and oil using microorganisms. It is a simple process that has mild operating conditions, high desulfurization efficiency, low energy consumption and less environmental pollution. However, there is still a lack of simple and efficient analytical methods for quantitatively analyzing the sulfur compounds in the biological desulfurization process. In order to solve this problem, the analytical method for the simultaneous determination of sulfite, thiosulfate and sulfide in biological desulfurization solutions by pre-column fluorescence derivation using high performance liquid chromatography (HPLC) was developed. The standard curves of sulfur species in this analytical method had good linear relationships with correlation coefficients of 0.999 5, 0.999 7, and 0.999 7 for sulfite, thiosulfate and sulfide, respectively. The detection limits of these sulfur compounds were 0.000 6, 0.000 7 and 0.001 1 μmol/L; the range of recovery rates were 98.17 to 101.9%, 100.9 to 102.6%, and 101.1 to 104.2%; which had good repeatability and stability. The analytical method was simple, efficient and accurate, and could be used to simultaneously determine the sulfur compounds in different biological desulfurization systems.

LC-MS/MS method for the differential diagnosis of treatable early onset inherited metabolic epilepsies.

Rapid diagnosis and early specific treatment of metabolic epilepsies due to inborn errors of metabolism (IEMs) is crucial to avoid irreversible sequalae. Nowadays, besides the profile analysis of amino- and organic acids, a range of additional targeted assays is used for the selective screening of those diseases. This strategy can lead to long turn-around times, repeated sampling and diagnostic delays. To replace those individual targeted assays, we developed a new liquid chromatography mass spectrometry method (LC-MS/MS) for the differential diagnosis of inherited metabolic epilepsies that are potentially treatable. The method was developed to simultaneously quantify 12 metabolites (sulfocysteine, guanidinoacetate, creatine, pipecolic acid, Δ1 -piperideine-6-carboxylate (P6C), proline, Δ1 -pyrroline-5-carboxylate (P5C), and the B6 -vitamers) enabling the diagnosis of nine different treatable IEMs presenting primarily with early-onset epilepsy. Plasma and urine samples were mixed with internal standards, precipitated and the supernatants were analyzed by LC-MS/MS. In comparison with previous assays, no derivatization of the metabolites is necessary for analysis. This LC-MS method was validated for quantitative results for all metabolites except P6C and P5C for which semiquantitative results were obtained due to the absence of commercially available standards. Coefficients of variation for all analytes were below 15% and recovery rates range between 80% and 120%. Analysis of patient samples with known IEMs demonstrated the diagnostic value of the method. The presented assay covers a selected panel of biochemical markers, improves the efficiency in the laboratory, and potentially leads to faster diagnoses and earlier treatment avoiding irreversible damage in patients affected with IEMs.

Assessing recovery rate methods: A review and application for human skeletal assemblages.

Recovery rates reflect the amount of recovered skeletal materials based on expectations about the total number of elements or individuals that should be present in an assemblage. It is an underlying concept that reflects analytical potential, wherein high recovery rates typically indicate high analytical capabilities. However, numerous methods are available to calculate different types of recovery rates, and each method addresses various types of research questions and utilizes different variables. Therefore, recovery rates cannot be applied and compared directly, and the appropriate recovery rate for any given research question must be considered thoughtfully. Several methods of determining individual and element recovery rates are applied to the USS Oklahoma commingled human remains assemblage and discussed with regard to their utility. Depending on which method is used, recovery rates range from 91 to 102% for the recovery of individuals and 0.02 to 91% for the recovery of elements within this assemblage. These results emphasize the need to carefully consider which recovery rate is most appropriate based on associated research questions and project contexts. We introduce the idea of the analytical recovery rate, a flexible concept to determine the potential assessment of biological profile parameters once individuation of commingled remains has occurred, wherein elements are selected based on the needs of the project as well as element preservation.

A new SERS substrate of self-assembled monolayer film of gold nanoparticles on silicon wafer for the rapid detection of polycyclic aromatic hydrocarbons

A facile and rapid method for the SERS detection of polycyclic aromatic hydrocarbons (PAHs) was reported. The Au colloids assemble to form gold nanoparticles (Au NPs) monolayer film at the air/water interface through the modification of n-dodecanethiol (DT), and then the film was directly transferred by tilt-lifting onto the silicon wafer to fabricate uniformed SERS substrate. PAHs could be preconcentrated into DT layer on the surface of the SERS substrate through the hydrophobic interaction, and detected by SERS. The linear range of detection for Benzo[a]-pyrene (B[a]P) is from 10−8 to 10−5 mol/L with a linearity (R2) of 0.92–0.99. The recovery rates range from 89.5% to 103.7%. The detection limit can reach the ng/L level. Pyrene (Pyr) and Chrysene (Chr) were also detected by SERS. The substrate had good stability, uniformity, reproducibility and reusability, which demonstrated that the DT-functionalized Au NPs film prepared by the self-assembly method at the air/water interface could be used as a reliable SERS candidate for the rapid analysis of PAHs.

A Comparative Study on Polyphenolic Composition of Berries from the Tibetan Plateau by UPLC-Q-Orbitrap MS System.

Five traditional medicinal food from the Tibetan plateau including Nitraria tangutorum Bobrov (NT), Hippophae rhamnoides L. (HR), Lycium ruthenicum Murray (LR), Lycium barbarum L. (LB) and Rubus corchorifolius L.f. (RC) are rich in phenolic compounds. However, the detailed studies about the phenolic compounds remain scarce. Therefore, we established a rapid method for the simultaneous identification and quantification of the phenolic compounds from berries via Ultra Performance Liquid Chromatography-Quadruple-Orbitrap MS system (UPLC-Q-Orbitrap MS). This method was verified from many aspects including detection limit, quantification limit, precision, repeatability, stability, average recovery rate and recovery range, and then was used to analyze the phenolic compounds in these five species of berries. Finally, a total of 21 phenolic compounds were directly identified by comparing the retention time and exact mass, of which 14 compounds were identified by us for the first time in berries from the Tibetan plateau, including one flavonoid aglycone (myricetin), 11 phenolic acids (gallic acid, protocatechuate, chlorogenic acid, vanillic acid, caffeic acid, syringic acid, p-coumaric acid, ferulic acid, 2-hydroxybenzeneacetic acid and ellagic acid), one flavanol (catechin) and one dihydrochalcone flavonoid (phloretin). Quantitative results showed that rutin, myricetin, quercetin and kaempferol were the main flavonoids. Moreover, a variety of phenolic acid compounds were also detected in most of the berries from the Tibetan plateau. Among these compounds, the contents of protocatechuate and chlorogenic acid were high, and high levels of catechin and phloretin were also detected in these plateau berries.

A signal on-off ratiometric electrochemical sensor coupled with a molecular imprinted polymer for selective and stable determination of imidacloprid

This work presents a signal on-off ratiometric electrochemical sensor coupled with a molecular imprinted polymer (MIP) for imidacloprid (IMI) determination. The ratiometric strategy corrects the detection results by setting 6-(Ferrocenyl)hexanethiol (FcHT) as an internal reference. The MIP membrane, as a molecular recognition receptor, has a three-dimensional structure and is complementary in the shape and chemical functionality to the template. The combination of a ratiometric strategy and MIP improves the sensitivity and selectivity of the sensors. The experimental parameters, such as monomer/template ratio, electropolymerization cycle and adsorption time, are optimized to improve the IMI sensing performance of the as-fabricated electrode. Under optimal electrochemical conditions, the proposed sensor is used to detect IMI in laboratory and real samples. In a range as wide as 5 × 10−7−1 × 10−4 mol L−1, a linear relationship is well established, and the value of the correlation coefficient is 0.9984. The limit of detection (LOD, S/N = 3) is well defined as 4.7 × 10−8 mol L−1. The recovery rates range from 97.4% to 103.5% while testing real samples. The fabricated electrode shows superior anti-interference ability for IMI determination in the presence of analogs at a higher level.

Facile synthesis of Fe3O4@Au core–shell nanocomposite as a recyclable magnetic surface enhanced Raman scattering substrate for thiram detection

The Fe3O4@Au core–shell nanocomposites, as the multifunctional magnetic surface enhanced Raman scattering (SERS) substrates, were fabricated successfully by the seeds growth method based on the Fe3O4–Au core-satellite nanocomposites. The SERS properties of the Fe3O4–Au core-satellite nanocomposites and the Fe3O4@Au core–shell nanocomposites were compared using 4-aminothiophenol (4-ATP) as the probe molecule. It was found that Fe3O4@Au core–shell nanocomposites showed better SERS performance than Fe3O4–Au core-satellite nanocomposites. The Au shell provided an effectively large surface area for forming sufficient plasmonic hot spots and capturing target molecules. The integration of magnetic core and plasmonic Au nanocrystals endowed the Fe3O4@Au core–shell nanocomposites with highly efficient magnetic separation and enrichment ability and abundant interparticle hot spots. The Fe3O4@Au core–shell nanocomposites could be easily recycled because of the intrinsic magnetism of the Fe3O4 cores and had good reproducibility of the SERS signals. For practical application, the Fe3O4@Au core–shell nanocomposites were also used to detect thiram. There was a good linear relationship between the SERS signal intensity and the concentration of thiram from 1 × 10−3 to 1 × 10−8 M and the limit of detection was 7.69 × 10−9 M. Moreover, residual thiram on apple peel was extracted and detected with a recovery rate range of 99.3%. The resulting substrate with high SERS activity, stability and strong magnetic responsivity makes the Fe3O4@Au core–shell nanocomposites a perfect choice for practical SERS detection applications.

Rapid detection of malachite green residues in fish using a surface-enhanced Raman scattering-active glass fiber paper prepared by in situ reduction method

Food safety issues, especially those related to drug residues, have caused concern in recent years. Malachite green (MG), which is frequently used as ectoparasiticide, fungicide, and antiseptic in fish farming, is poisonous and carcinogenic. Several technologies and methods have been developed to accurately detect MG, but they can be time-consuming and expensive. Herein, we prepared a glass fiber paper as a surface-enhanced Raman scattering substrate for rapid and convenient detection of MG residues in fish. Uniform silver nanoparticles were deposited on the glass fiber paper by two in situ reduction steps of silver nitrate. The Raman signal of MG was detected and recorded using a portable Raman spectrometer in 10 s. There was a good linear relationship between the surface-enhanced Raman scattering signal intensity and the concentration of MG between 1 × 10−7 and 1 × 10−5 mol/L and the limit of detection was 5 × 10−10 mol/L. Residual MG in fish samples was extracted and detected with a recovery rate range of 98.9–119.4%. This method provides a novel way to detect MG in fish.

A New Spectrophometric Method For The Analysis Of Fructose, Glucose And Sucrose, Using 2-Thiobarbituric Acid And Zero-Valent Iron Powder (ZVIP)

A new spectrophotometric method has been developed for the determination of fructose, glucose and sucrose in fruit juices. The method is based on the oxidation of sugars with zero valent iron powder in acidic pH aqueous solution and bubbled with air. Oxidized by-products were complexed with 2-thiobarbituric and monitored by UV-Vis spectroscopy. The recorded spectra are specifically characteristic for fructose, glucose and sucrose respectively. Calibration curves were studied for each compound and the quantitative determination of carbohydrate concentrations was carried out using an internal standard addition method. The average relative standard deviation is 4% and recovery rate range from 98% to 103% for spiked concentrations of 0.05 – 4 mM carbohydrates. The detection limit are 13, 15 and 12 µM for fructose, glucose and sucrose respectively. The oxidation of carbohydrates gives rise to certain by-products, presents a new method of indirect measurement of carbohydrates. This method is applied in the determination of carbohydrates in juices and other foods in a precise, easy and inexpensive way.

Study of effective utilization of iron ore sinter through arc plasma

Generation of fines is common in mining, sizing, and beneficiation and also in high-temperature metallurgical processes as the disintegration of agglomerate/compact occurs. Extraction of metallic iron from ore fines is one of the challenging aspects of iron making industries as the liberation of fines blocks, the charge burden porosity and hence hinders the reduction rate. Along with size factor, mineral composition plays a vital role in the extraction process; particularly silica. As silica has the very high tendency towards iron oxide, at comparatively low temperature, the activity of silica should be suppressed to prevent silicate phases. Adjustment of such conditions is controlled by addition of lime, but sometimes excessive slag generation increases the cost of production. In the present work, carbothermic reduction of partially reduced iron bearing pellets has been melted through 20 KW DC arc plasma furnace, and a comparative study has been made for considering different slag chemistry approaches. Pellets as aforementioned are made available from Patnaik Steel and Alloys Ltd, Odisha, having high silica content ore fines (of about 8.6%) as obtained from the chemical analysis. X-Ray analysis and optical image analyzer result of sinter thus obtained reveal that fayalite phase has major fractional value. Smelting works were done for sinter with/without adjustment of slag chemistry, where argon and nitrogen were used as plasma forming gases. A range of recovery rates (between 87-94%) is achieved by charge composition, ionizing gases, and smelting duration. It is observed that use of nitrogen as plasma forming gas increases the recovery rate than that of using only argon plasma; due to high energy flux of nitrogen which increases the enthalpy due to its diatomicity. A maximum recovery rate of about 94% is achieved for process duration of 13minutes utilizing nitrogen plasma. Smelting of charge with the addition of hydrated lime targeting melilite as final slag resulted in the formation of metallic iron as confirmed from XRD and XRF analyses. In the other hand, ferrosilicon is liberated in the metallic parts where smelting of charge was done without adjustment of slag chemistry. Both metal and slag thus obtained are characterized by XRD, XRF, microhardness and wet chemical analysis suitably.

Promoting information diffusion through interlayer recovery processes in multiplex networks.

For information diffusion in multiplex networks, the effect of interlayer contagion on spreading dynamics has been explored in different settings. Nevertheless, the impact of interlayer recovery processes, i.e., the transition of nodes to stiflers in all layers after they become stiflers in any layer, still remains unclear. In this paper, we propose a modified ignorant-spreader-stifler model of rumor spreading equipped with an interlayer recovery mechanism. We find that the information diffusion can be effectively promoted for a range of interlayer recovery rates. By combining the mean-field approximation and the Markov chain approach, we derive the evolution equations of the diffusion process in two-layer homogeneous multiplex networks. The optimal interlayer recovery rate that achieves the maximal enhancement can be calculated by solving the equations numerically. In addition, we find that the promoting effect on a certain layer can be strengthened if information spreads more extensively within the counterpart layer. When applying the model to two-layer scale-free multiplex networks, with or without degree correlation, similar promoting effect is also observed in simulations. Our work indicates that the interlayer recovery process is beneficial to information diffusion in multiplex networks, which may have implications for designing efficient spreading strategies.

Determination of Tributyltin in Seafood Based on Magnetic Molecularly Imprinted Polymers Coupled with High-Performance Liquid Chromatography-Inductively Coupled Plasma Mass Spectrometry

In this study, Fe3O4 was adopted as a carrier for surface molecular imprinting with two-stage polymerization. First, the functional monomer (methacrylic acid, MAA) was modified on the surface of Fe3O4, which was then polymerized with the template molecule (tributyltin, TBT), cross linking agent (ethylene glycol dimethacrylate, EGDMA), and porogen (acetonitrile), hereby successfully preparing Fe3O4@MIPs prone to specifically identify TBT. The physical properties of Fe3O4@MIPs were then characterized, and adsorption and selection capacities were also assessed. Compared with conventional imprinting polymers, this magnetic molecular imprinting polymer (MIP) displayed significantly increased and more specific adsorption. Meanwhile, its pretreatment was simpler and faster due to magnetic separation characteristics. Using magnetic MIPs as adsorbents for enrichment and separation, detection limit, recovery rate, and linear range were 1.0 ng g−1, 79.74–95.72%, and 5 ng g−1~1000 ng g−1, respectively, for a number of seafood samples. High-performance liquid chromatography-inductively coupled plasma mass spectrometry (HPLC-ICP-MS) was used to analyze Tegillarca granosa, mussels, large yellow croaker, and other specimens, with recovery rates of 79.74–95.72% and RSD of 1.3%–4.7%. Overall, this method has a shorter total analysis time, lower detection limit, and wider linear range and can be more effectively applied to determine MAA in seawater and seafood.

Simultaneous determination of 8 main compounds in Eclipta Herba by UPLC

To establish an UPLC method for the simultaneous determination of 8 compounds in Eclipta Herba, such as isoquercitrin, luteoloside, demethylwedelolactone, isochlorogenic acid A, isochlorogenic acid C, luteolin, wedelolactone and apigenin. The experiment was performed with a Waters Acquity UPLC BEH C₁₈ (2.1 mm×100 mm, 1.7 μm) column by gradient elution of 0.1% formic acid in water and acetonitrile: 0-4 min,10%-13% A; 4-10 min, 13%-16% A; 10-13 min, 16%-25% A; 13-17 min, 25%-28% A; 17-20 min,28%-40% A;20-25 min,40%-95% A. The flow rate was 0.3 mL•min⁻¹.. The condition of was the colum temperature was maintained at 35 ℃ and the detected wavelength was set at 350 mm. 8 components were separated clearly by this method. Also a good linearity was obtained between the chosen concentration(r≥0.999 0). The measured data showed that the recovery rate range from 96.60%-103.4% (n=6) and their RSD values were 0.86%-2.4%. The method has high recovery rate, good reproducibility and stability. It provides a scientific basis for the identification and quality evaluation of Eclipta Herba.

Electrochemical Molecular Imprinted Sensors Based on Electrospun Nanofiber and Determination of Ascorbic Acid.

In this study, electrochemical molecularly imprinted sensors were fabricated and used for the determination of ascorbic acid (AA). Nanofiber membranes of cellulose acetate (CA)/multi-walled carbon nanotubes (MWCNTs)/polyvinylpyrrolidone (PVP) (CA/MWCNTs/PVP) were prepared by electrospinning technique. After being transferred to a glass carbon electrode (GC), the nanofiber interface was further polymerized with pyrrole through electrochemical cyclic voltammetry (CV) technique. Meanwhile, target molecules (such as AA) were embedded into the polypyrrole through the hydrogen bond. The effects of monomer concentration (pyrrole), the number of scan cycles and scan rates of polymerization were optimized. Differential pulse voltammetry (DPV) tests indicated that the oxidation current of AA (the selected target) were higher than that of the structural analogues, which illustrated the selective recognition of AA by molecularly imprinted sensors. Simultaneously, the molecularly imprinted sensors had larger oxidation current of AA than non-imprinted sensors in the processes of rebinding. The electrochemical measurements showed that the molecularly imprinted sensors demonstrated good identification behavior for the detection of AA with a linear range of 10.0 - 1000 μM, a low detection limit down to 3 μM (S/N = 3), and a recovery rate range from 94.0 to 108.8%. Therefore, the electrochemical molecularly imprinted sensors can be used for the recognition and detection of AA without any time-consuming elution. The method presented here demonstrates the great potential for electrospun nanofibers and MWCNTs to construct electrochemical sensors.

Influence of four-end HTM (high temperature membrane) parameters on the thermodynamic and economic characteristics of a supercritical power plant

An oxy-type power plant was analyzed in this paper, equipped with a hard-coal-fired pulverized fuel boiler, a steam turbine, a CO2 capture unit and an ASU (air separation unit) with a four-end-type high-temperature membrane. The gross electrical power of the plant is 600 MW; the live and reheated steam parameters are 650 °C/30 MPa and 670 °C/6 MPa, respectively. In this paper, computations were performed for three air compressor pressure ratios (β = 15; 20; 30) and a range of oxygen recovery rate (50% ≤ R ≤ ∼99%). The net efficiency of the oxy-type plant reached 38.7% compared to 46.5% for the reference plant. The equation to calculate a membrane area was derived in this paper. The defining dependence relationship between the R and β was also derived. The total investment costs for the ASU and the entire plant was determined as a function of R and β. Similarly, the break-even price of electricity and its individual components were determined. The break-even price for R ≈ 98% and β = 15 is 1.73 EUR/MWh higher than for the reference plant (63.14 EUR/MWh). In the conducted risk analysis, a Monte Carlo method was used. With a probability of 50%, the break-even price for the oxy-type and reference plants are ≤67.05 EUR/MWh and ≤69.98 EUR/MWh, respectively.

Comparison and Development of CLIA and ELISA for Detection of Sudan I in Food Sample

Two immunological methods, ELISA and CLIA were optimized and compared. The sensitivity of CLIA was higher. The optimized CL-ELISA allowed the Sudan I detection in a linear range of 0.156-5 ng mL-1, the IC50 was 0.642ng mL-1 and the limit of detection (LOD) was 0.05ng mL-1. The method showed good recoveries with spiked chili powder. The recovery rate range from 97.28-112.39%. The proposed method proved to be efficient for the detection of Sudan I in food samples.

Study on the Highly Sensitive AChE Electrode Based on Multiwalled Carbon Nanotubes

Using chitosan (CS) as carrier, the method named layer‐by‐layer (LBL) self‐assembly modification to modify the glassy carbon electrode (GCE) with multiwalled carbon nanotubes (MWNTs) and acetylcholine esterase (AChE) was proposed to prepare the acetylcholine esterase electrode with high sensitivity and stability. The modified electrode was used to detect pesticide of aldicarb, and the enzyme inhibition rate of the electrode showed good linearity with pesticide concentrations in the range of 10−10 g·L−1 to 10−3 g·L−1. The detection limit was 10−11 g·L−1. The modified electrode was also used to detect the actual sample, and the recovery rate range was from 97.72% to 107.15%, which could meet the rapid testing need of the aldicarb residue. After being stored in the phosphate buffer solution (PBS) in 4°C for 30 days, the modified electrode showed good stability with the response current that was 80% of the original current.

A validated high performance liquid chromatograph-photodiode array method for simultaneous determination of 10 bioactive components in compound hongdoushan capsule.

Background:The compound Hongdoushan capsule (CHC) is widely known as compound herbal preparation and is often used to treat ovarian cancer and breast cancer, and to enhance the body immunity, etc., in clinical practice.Objective:To determine simultaneously 10 bioactive components from CHC, namely glycyrrhetinic acid, liquiritin, glycyrrhizin, baccatin III, 10-deacetylbaccatin III, cephalomannine, taxol, ginsenoside Rg1, ginsenoside Re, and ginsenoside Rb1.Materials and Methods:A high performance liquid chromatograph method coupled with photodiode array detector was developed and validated for the 1st time. Chromatographic analysis was performed on a SHIMADZU C18 by utilizing a gradient elution program. The mobile phase was acetonitrile (A)-water (B) at a flow rate of 0.8 mL/min.Results:The calibration curve was linear over the investigated concentration ranges with the values of r2 higher than 0.9993 for all the 10 bioactive components. The average recovery rates range from 98.4% to 100.5% with relative standard deviations ≤2.9%. The developed method was successfully applied to analyze 10 compounds in six CHC samples from different batches. In addition, the herbal sources of 32 chromatographic peaks were identified through comparative studying on chromatograms of standard, the respective extracts of Hongdoushan, RenShen, GanCao, and CHC.Conclusion:All the results imply that the accurate and reproducible method developed has high separation rate and enables the determination of 10 bioactive components in a single run for the quality control of CHC.

Investigating the Translocation and Seeding of WildHaliotis mariaeWood, 1828, in the Sultanate of Oman

Restocking and potential stock enhancement of natural abalone stocks by seeding hatchery-reared juvenile abalone into suitable habitat is currently being investigated or implemented in a number of countries, including Japan, Australia, New Zealand, Mexico, and South Africa. A series of experiments has been conducted to investigate the feasibility and development of the technology required to do this in the Sultanate of Oman. Wild seed were collected between Mirbat and Ras Atian on the Dhofar coast and kept in a hatchery for 7 wk. Qualitative and observational data were used to develop seeding site selection criteria and a seeding density of 10 juveniles/m2. The juveniles were relocated and seeded in 18 different sites spread over a distance of 72 km. Sites selected with an abundance of boulders with a diameter of less than 50 cm yielded the highest recovery rates. Different categories of habitat availability and selection by seeded juveniles for specific habitat categories varied significantly among sites, which was reflected in the range of recovery rates. Boulder habitats less than 50 cm in diameter supported the most recovered juveniles (P = 0.002 and P = 0.005). Survival rates over a period of 30, 60, and 90 days ranged from 0%–80% and proved highly site specific (P = 0.04). A positive correlation was found between average seed size and increased recovery rates (P = 0.015, R2 = 0.25). Dispersal was limited in sites with high recovery rates. Site selection was shown to be vital. A simple seeding mechanism comprising a PVC tube proves successful as an alternative to seeding by hand.