Reaction Volume Research Articles

Optimization of an amplicon sequencing-based microsatellite panel and protocol for stock identification and kinship inference of lake trout (Salvelinus namaycush).

Kinship-based methods of population assessment such as close-kin mark-recapture require accurate and efficient genotyping methods capable of resolving complex relationships among kin. Inference of such relationships can be difficult using biallelic loci due to the large number of markers required to obtain the necessary power. Sequencing-based microsatellite panels offer an efficient alternative, combining high polymorphism with efficient next-generation methods. Here we construct, optimize, and test one such panel for lake trout (Salvelinus namaycush) using a combination of previously-published loci adapted for sequencing and de novo loci mined from a genome assembly. We performed three rounds of primer optimization, yielding a final panel of 131 loci, followed by testing with two different levels of PCR multiplexing (all primers in one or two groups) and two different reaction volumes (5 and 10 μL). Our results showed that the use of the largest multiplex and smallest reaction volume did not substantially change results, allowing significant cost and time savings. To test panel accuracy, we used both a set of 153 known-origin samples from origins of management interest and a series of hatchery crosses representing nine families with parent-offspring, half-sibling, and largely-unrelated pairs. Our results indicate that sequencing-based microsatellite panels can efficiently and accurately provide the information required for a population genetics analyses including population assignment, calculation of between-population F ST, and kinship-based population estimation techniques. Such techniques are seeing increasing applications for a wide range of taxa; our findings should provide insight and guidance for the development of the necessary molecular resources.

Processing of Coal into Coke with the Pyrolysis Method

Utilization of coal as a direct fuel can cause environmental problems such as solid waste in the form of fly ash (flyash). This study aims to process coal into coke using the pyrolysis method in the hope of increasing the quality and efficiency of coal that is safe for the environment. This research was conducted in 3 stages. The first stage was carried out by crushing coal, sieving coal, testing proximate and ultimate coal, and analyzing the calorific value of coal. The second stage is carried out by preparing coal, pyrolysis of coal using a set of pyrolysis tools. Pyrolysis was operated at ± 400oC using a stainless reactor with a reactor volume capacity of 16 liters. Pyrolysis is carried out until no more liquid smoke is produced. The third stage was carried out by crushing the coke product, testing the proximate and ultimate coke (moisture content, ash content, volatile matter, fixed carbon, total sulfur), and analyzing the calorific value of the coke. The results showed that the quality of coal could be improved by processing it into coke using the pyrolysis method as evidenced by a decrease in water content, a decrease in volatile matter, an increase in fixed carbon, and an increase in calorific value

Influence of Filler Concentration on the Mechanical Properties of a Polymer Composite

The results of a study of carbon fiber-filled samples with an epoxy amine-cured matrix are presented. Independent quasi-periodic oscillations of the density and Young's modulus were recorded for the first time, against the backdrop of a monotonic increase in the strength of the samples. The probable causes of the appearance of the vibrational kinetics of the physico-mechanical parameters of the composite are determined depending on the content of the filler in the reaction volume of constant magnitude.

Shaping of Porous CeO2 Powders into Highly Active Catalyst Carriers.

CeO2 is attracting more and more attention because of its outstanding performance in heterogeneous catalysis, as an active support and a reaction promoter in reactions of industrial interest. We herein describe a novel and scalable manufacturing process of mm-sized CeO2 spheres by a combination of extrusion and spheronization of CeO2 porous powders. In this study, wet paste formulation and fabrication procedures were optimized, and as a result methylcellulose was identified as the best plasticizer for paste extrusion to provide well-defined spherical shapes and smooth surfaces, as well as reproducible batches. After nickel impregnation (10 wt %), the catalytic performance of CeO2 supports was evaluated in the CO2 methanation reaction (T = 250-350 °C, P = 5 bar·g) and compared with that of commercial Al2O3 spheres doped or not with CeO2. These novel CeO2-based catalysts are easily reduced at a moderate temperature and more active than the Al2O3 analogues, particularly at low reaction temperatures and small reactor volumes, properties that make their implementation in emerging reactor configurations very promising.

KINETIC REGULARITIES OF THE CATALYTIC OXIDATION OF ISOBUTYLENE TO METHYLACROLEIN ON AN ANTIMONY-TIN CATALYST

The parameters that determine the choice of the reactor are the reactor power, catalyst activity (intensity per unit volume), the total required amount of catalyst, the value of the adiabatic change in the temperature of the reaction mixture at complete conversion, the nature of the change in the reaction rate and selectivity with the depth of conversion, etc. the results of the theoretical optimization showed the need for the implementation of the process of partial oxidation of isobutylene to methylacrolein on an antimony-tin oxide catalyst in an isothermal reactor. To determine the optimal conditions for conducting the process on an antimony-tin catalyst, the choice of the type and main structural dimensions of the reactor for the partial catalytic oxidation of isobutylene to methylacrolein, we used the method of mathematical modeling, which is based on data on the rates of chemical transformation. To obtain quantitative characteristics, a series of experiments was carried out by influence of the composition of the reaction mixture and the rate of the oxidation of isobutylene to methylacrolein. The kinetic regularities of the process of catalytic oxidation of isobutylene to methylacrolein on an antimony-tin catalyst were recorded on a flow-type unit with a small volume reactor without a gradient. Reaching the stationary regime in this reactor occurs in 15–25 minutes

Isobutanol to isobutene: Processes and catalysts

The present review aims at summarizing the scientific literature data and patents concerning the isobutanol, preferably from a fermentation process, selective dehydration reaction to produce isobutene (isobutylene). The benefits and drawbacks of the conditions used on the process design and catalyst performances are illustrated, analyzed and discussed with much objectivity. Thermodynamic equilibria of the various reactants and products are provided together with the limiting step rate. Isobutanol selective dehydration to isobutene can be done under low or high pressure conditions. This choice impacts not only the downstream recovery and purification of isobutene, but also the stability of the catalyst and the reactor volume. Due to the strong inhibition of the alumina catalysts by steam, the reaction under pressure requires longer contact times and catalyst volume. The alumina catalysts need to have a good hydrothermal stability to avoid a rapid deactivation. Isobutene purification is also addressed. The impact of the water partial pressure on the catalytic dehydration is described and shown to affect the side reactions. Mass transfer limitations and kinetics of the reaction are well documented. Relevant advices are provided to perform the reaction without undesired products.

Fuzzy Automatic Control of the Pyrolysis Process for the Municipal Solid Waste of Variable Composition

control of the pyrolysis process of municipal solid waste (MSW) of variable composition and moisture content. The fuzzy control method is developed and studied that makes it possible to carry out the proper automatic control of the pyrolysis plant with the determination of the optimal ratio of air/MSW for various types of waste and with different moisture content values to ensure high efficiency of the MSW disposal process. The effectiveness study of the proposed fuzzy control method is performed in this paper on a specific example, in particular, when automating the pyrolysis plant for the MSW disposal with the reactor volume of 250 liters. The obtained simulation results confirm the high efficiency of the developed method, as well as the feasibility of its use for designing automatic control systems of various pyrolysis plants that operate under conditions of changes in the composition and moisture content of input waste.

An SPRI beads-based DNA purification strategy for flexibility and cost-effectiveness

BackgroundCurrent solid-phase reversible immobilization (SPRI) beads technology is widely used in molecular biology due to its convenience for DNA manipulation. However, the high performance commercial SPRI beads have no price advantage over our method. Furthermore, the use of commercially available SPRI beads standards does not provide the flexibility required for a number of specific nucleic acid handling scenarios.ResultsWe report an efficient DNA purification strategy by combining home-made beads-suspension buffer with SPRI beads. The method tests the critical concentrations of polyethylene glycol (PEG) 8000 and beads to maximise recovery. And the composition of the SPRI beads DNA purification system (SDPS) was determined at 20% PEG 8000, 2 M NaCl and 16.3 mM MgCl2, and 1.25 mg/ml beads (1/8th original concentration). Then, we tested the DNA recovery of the SDPS, and the result showed that it was comparable to the control (AMPure XP beads). In the study, we have also developed an adjustment SPRI beads DNA purification system (ASDPS), the volume of ASDPS per reaction is 0.6× reaction volume (beads/samples). The performance of ASDPS is similar to SDPS and the control. But the cost of our methods is only about 1/24th of the control. To further assess its performance, we prepare the DNA-seq libraries to evaluate the yield, library quality, capture efficiency and consistency. We have compared all these results with the performance of the control and confirmed its efficiency.ConclusionWe have proposed an alternative DNA purification approach with great flexibility, allowing researchers to manipulate DNA in different conditions. And ultimately, its application will benefit molecular biology research in the future.

Biogas upgrading in a pilot-scale trickle bed reactor – Long-term biological methanation under real application conditions

The biological methanation of H2 and CO2 in trickle bed reactors is one promising energy conversion technology for energy storage, but experiences at pilot-scale under real application conditions are still rare. Therefore, a trickle bed reactor with a reaction volume of 0.8 m3 was constructed and installed in a wastewater treatment plant to upgrade raw biogas from the local digester. The biogas H2S concentration of about200 ppm was reduced by half, but an artificial sulfur source was required to completely satisfy the sulfur demand of the methanogens. Increasing the ammonium concentration to > 400 mg/L was the most successful pH control strategy, enabling stable long-term biogas upgrading at a CH4 production of 6.1 m3/(m3RV·d) with synthetic natural gas quality (CH4 > 98%). The results of this study with a reactor operation period of nearly 450 days, including two shutdowns, represents an important step towards the necessary full-scale integration.

Biomass-sulfur-based mixotrophic denitrification (BSMD) process for synthetic and real wastewater treatment: Engineering application, applicable scope, and operational strategy

Elemental-sulfur-driven autotrophic denitrification (ESDAD) process is widely used in sewage treatment, while its low denitrification capacity has become the bottleneck of this technology. The biomass-sulfur-based mixotrophic denitrification (BSMD) process is a promising denitrification pathway to improve nitrate removal of sewage. Based on previous research, a comparative analysis of the ESDAD and BSMD processes was adopted in this study. Then, three lab-scale reactors were constructed with various BSMD filters to investigate the characteristics of the BSMD process, and the optimal BSMD filter (F3) with the nitrate removal rate (NRR) of 556 ± 13.6 mg NO3–-N·L−1·d−1 was 3:1:1 by weight ratio of sulfur powder to rice straw powder to shell powder. Additionally, a pilot-scale reactor (volume: 1000 L) filled with filter F3 was designed and operated to treat the effluent of a municipal secondary tank. The feasibility of the BSMD process in engineering application was demonstrated, accompanied by a desirable treatment capacity (hydraulic retention time (HRT) ≤ 1 h) under varying conditions. Moreover, autotrophs and heterotrophs co-existed along the pilot-scale reactor, and the autotrophs remained dominant at seasonal temperatures. In general, the prospect of the BSMD is attractive, and the outcomes of this study could provide guidance for the operation of the BSMD process.

Continuous Flow Inter- and Intramolecular Macrolactonization under High Dilution Conditions.

An efficient continuous flow process for the macrolactonization of seco acids and diacids using diols in the presence of Mukaiyama reagent (N-methyl-2-chloropyridinium iodide) has been developed for medium to large sized macrocyclic lactones. In comparison with other methods, the continuous flow process provided good to high yield in a short reaction time. By using this methodology, a wide range of macrocyclic lactones (11 compounds), dilactones (15 compounds), and tetralactone derivatives (2 compounds) with various ring sizes (12-26 atoms in the core) were synthesized in just 35 min of residence time. Advantageously, macrolactonization under the flow process is very elegant to handle the high dilution of reactants with a defined perfluoroalkoxy alkanes (PFA) tube reactor volume (7 mL).

Alternative Strategies for Effective Utilization of Carbon Dioxide in Dimethyl Ether Synthesis

AbstractConverting CO2 into chemicals, e.g., methanol and dimethyl ether (DME), has been an attractive way to protect the global environment. In this process, the total catalyst volume of the methanol reactor was split into two sections to load the reactors. The catalyst volume of each reactor was optimized by the differential evolution technique. It was concluded that the indirect route yields a higher DME production rate than the direct one, as it produces higher amounts of methanol. CO2 conversions increased by 79 % in the indirect two‐stage process, which resulted in the highest DME production rate of 343 t per day. The results demonstrate how the concept of a two‐stage process in the indirect conversion of CO2 is feasible and beneficial for fuel production.

A re-useable microreactor for dynamic and sensitive photocatalytic measurements: Exemplified by the photoconversion of ethanol on Pt-loaded titania P25.

Despite numerous advancements in synthesizing photoactive materials, the evaluation of their catalytic performance remains challenging since their fabrication often involves tedious strategies, yielding only low quantities in the μ-gram scale. In addition, these model catalysts exhibit different forms, such as powders or film(-like) structures grown on various supporting materials. Herein, we present a versatile gas phase μ-photoreactor, compatible with different catalyst morphologies, which is, in contrast to existing systems, re-openable and -useable, allowing not only post-characterization of the photocatalytic material but also enabling catalyst screening studies in short experimental time intervals. Sensitive and time-resolved reaction monitoring at ambient pressure is realized by a lid-integrated capillary, transmitting the entire gas flow from the reactor chamber to a quadrupole mass spectrometer. Due to the microfabrication of the lid from borosilicate as base material, 88% of the geometrical area can be illuminated by a light source, further enhancing sensitivity. Gas dependent flow rates through the capillary were experimentally determined to be 1015-1016 molecules s-1, and in combination with a reactor volume of 10.5 μl, this results in residence times below 40s. Furthermore, the reactor volume can easily be altered by adjusting the height of the polymeric sealing material. The successful operation of the reactor is demonstrated by selective ethanol oxidation over Pt-loaded TiO2 (P25), which serves to exemplify product analysis from dark-illumination difference spectra.

Comparison of MBR and MBBR followed by UV or electrochemical disinfection for decentralized greywater treatment

Greywater is an attractive source for water reuse at the household or building level, particularly for non-potable applications. Two greywater treatment approaches are membrane bioreactors (MBR) and moving bed biofilm reactors (MBBR), yet, their performance has not been compared so far within their respective treatment flowsheets, including post-disinfection. Two lab-scale treatment trains were operated on synthetic greywater: a) MBR with either polymeric (chlorinated polyethylene, C-PE, 165 days) or ceramic (silicon carbide, SiC, 199 days) membranes coupled with UV disinfection; and b) single-stage (66 days) or two-stage (124 days) MBBR coupled with an electrochemical cell (EC) for in-situ disinfectant generation. Water quality was constantly monitored, and Escherichia coli log removals were assessed through spike tests. Under low-flux operation of the MBR (<8 L·m − 2·h − 1), the SiC membranes delayed the onset of membrane fouling and needed less frequent cleaning compared to C-PE membranes. Both treatment systems met most water quality requirements for unrestricted greywater reuse, at a 10-fold lower reactor volume for the MBR than the MBBR. However, neither the MBR nor the two-staged MBBR allowed adequate nitrogen removal, and the MBBR did not consistently meet effluent chemical oxygen demand and turbidity requirements. Both EC and UV provided non-detectable E. coli concentrations in the effluent. Although the EC provided residual disinfection, scaling and fouling decreased its energetic and disinfection performance over time, making it less efficient than UV disinfection. Several outlines to improve the performance of both treatment trains and disinfection processes are proposed, thus, allowing a fit-for-use approach that leverages the advantages of the respective treatment trains. Results from this investigation will assist in elucidating the most efficient, robust, and low-maintenance technology and configurations for small-scale greywater treatment for reuse.

Optimization of the content of isobutane in the feed stream of the plant for sulfuric acid alkylation of isobutane with olefins

The raw materials for the industrial production of moto- and air-alkylates are isobutane and butane-butylene fractions containing in their composition a component, n-butane, which is inert for the reaction of sulfuric acid alkylation of isobutane with olefins. In accordance with the Specifications TU 0272-024-00151638-99, the content of n-butane in the isobutane fraction, depending on the grade of the fraction, is 0.7÷20% wt. Its presence reduces the useful reaction volume of the alkylation reactor, and when separating the components of the alkylation reaction mass, it is necessary to use a distillation column (debutanizer). The possibility of including an additional column in the technological scheme for removing n-butane from the composition of the fraction (respectively, isobutane concentration) before it is fed into the alkylation reactor is being considered. This is of particular importance for factions with a brand below "High Brand". The study is conducted using the Honeywell UniSim Design software system. The Peng-Robinson method was used to calculate the properties of process stream components. The theoretically optimal design of the apparatus was calculated: when using a distillation column with a pressure in the apparatus of about 400 kPa to reduce the content of n-propane in the distillate (obtained isobutane fraction) to 0.001 mol. the share will require 48 theoretical plates, the accepted reflux ratio R = 8.9, the temperatures in the condenser and reboiler are 26.88 and 47.27 °C, respectively. A computational experiment has shown that in order to achieve the practical absence of n-butane in the obtained isobutane fraction (concentration of about 0.1% wt.), it is possible to use a distillation column with the following technological modes: the number of plates is 60, the feed plate is 15, the efficiency of contact devices is 0.8; the pressure in the column is about 400 kPa, the temperature in the condenser and reboiler is Тk=28.91÷29.05 ℃ and Тр=46.72÷47.25 ℃, respectively, reflux ratio R=20.41. This fraction also does not contain pentanes.

Efficient organic carbon utilization for combined nutrient removal and biogas production in hybrid biofilm activated sludge system

Moving bed biofilm technology is a successful and promising biological treatment process considered for cost-effective management of wastewaters. In this study, a hybrid moving bed biofilm pilot plant was operated and obtained results were compared with simulation results of two biological processes: a conventional Biological Nutrient Removal (BNR) system and a novel hybrid activated sludge configuration implemented with Moving Bed Biofilm Reactor (MBBR) and a reactive primary clarifier (RPC). An efficient organic carbon entrapment (87%) was obtained in reactive primary clarifier where the major component (95%) of the total Chemical Oxygen Demand (COD) was determined as slowly hydrolysable (XS1), according to respirometric tests. Pilot plant and simulation studies exhibited that an improved nitrogen and phosphorus removal performance, as well as higher biogas production (47%) were obtained by organic carbon redirection in proposed hybrid configurations, securing a 40% less reactor volume. Investigation of the economic aspects indicated that hybrid system has a lower operating cost (i.e., 23% less air requirement, 40% less mixing energy requirement), does not require internal recirculation pumps, and produces more energy through anaerobic digestion compared to conventional BNR. Therefore, proposed novel hybrid configuration is more efficient for the treatment of municipal wastewater in terms of Capital Expenditures (CAPEX) and Operational Expenditures (OPEX) within the energy self-sufficient treatment plant approach and sustainable treatment plant operation.

Design of reactor for the production of zinc oxide nanoparticles

This study aims to design a continuous stirred tank reactor (CSTR) type reactor to produce zinc oxide (ZnO) nanoparticles. Mass balance calculations were carried out in this study as a benchmark to determine whether the reactor was working properly by knowing the flow of incoming raw materials and the products produced by the reactor. Furthermore, the reactor's design and the stirrer used in the reactor are calculated manually using Microsoft Excel. Based on the calculation results of the reactor design, the reactor volume is 8224.359 liters, with a vessel diameter of 73.298 in, a cylinder height of 166.090 in, and a cylinder thickness of 73.444 in. The top cover of the reactor measures 12.387 inches with a thickness of 0.072 inches, while the bottom cover measures 21.185 inches with a thickness of 0.083 inches, so the overall height of the reactor is 37.552 in. The reactor is equipped with one stirrer with an impeller diameter of 36.722 in, impeller height from the bottom of the tank is 24.433 in, impeller width is 7.344 in, and impeller length is 9.180 in. Turbulent stirring flow conditions with a standard motor power for the stirrer is 6.849 HP. This design will be a reference for building more economical, efficient, and highly demanding reactors.

Rapid Screening of Barley Stripe Mosaic Virus Via Microfluidic Chip Method

<i>Barley stripe mosaic virus</i>, the type member of <i>Hordeivirus</i>, constitutes an important seed-transmitted pathogen distributed in almost every barley growing area worldwide. Researches on efficient detection of BSMV suitable in wild application are in urgent need. New platforms like microfluidic technology keep progressing rapidly in past decades and gains increasing influence on life sciences. Thus in this study, one rapid screening method for BSMV via microfluidic chip was established. Through method validity, we succeeded in demonstrating the amplification of BSMV within 30 min at one constant temperature using a microfluidic chip assay. Sensitivity analysis conformed that this method obtained a detection limit at 1.00×102 copies/μL, which was even more sensitive than real-time RT-PCR. <i>Maize chlorotic mottle virus</i>, <i>Maize dwarf mosaic virus</i>, <i>Oat mosaic virus</i>, and <i>Wheat streak mosaic virus</i> were chosen in specificity test along with BSMV, but only BSMV expressed typical amplification curves and Ct. Microfluidic analytic systems realize miniaturization by reducing the reaction volume to just 5 μL, which has several superiorities such as saving expensive reagents and reducing inspection costs. Moreover this microfluidic chip assay can simultaneously detect a variety of viruses, and the whole process takes just 1 hour, which greatly speeds up the detection and improves efficiency. All in all, this microfluidic chip method has the potential to be further implemented by phytosanitary services for routine diagnose as well as rapid screening in places like ports.

In-situ release and sequestration of CO2 in cement composites using LTA zeolites

This paper investigates the impact of in-situ release and sequestration of CO2 on the compressive strength, volume of permeable voids, phase change, hydration reaction, and micro-morphology of cement mortars. Two Linde Type A (LTA) zeolites with micro-pore dimensions of 5 Å and 4 Å (i.e., LTA 5A and 4A zeolites) were employed as CO2 carriers herein. The incorporation of 312 wt% plain LTA 5A and 4A zeolites increases the 1-day compressive strength of the mortars. However, the use of plain LTA 5A zeolite shows marginal contributions to the 7 and 28-day compressive strengths of the mortars, whilst using plain LTA 4A zeolite even deteriorates their 7 and 28-day compressive strengths. The micro-structural analyses reveal that the addition of LTA zeolites promotes the cement hydration and improves the mean chain length (MCL) of calcium aluminosilicate hydrates (C-A-S-H). Nevertheless, this introduces numerous weak points or even a porous structure to the cement matrix. In contrast, in-situ release of CO2 via LTA zeolites significantly enhances the compressive strengths of the mortars at various ages, as this can further facilitate the hydration evolution and improve the MCL of C-A-S-H. Moreover, in-situ release of CO2 brings an incremental content of calcium carbonates. The calcium carbonate contents in the specimens containing 12 wt% LTA 5A and 4A zeolites are increased by 5.3 wt% and 4.8 wt%, respectively. This leads to homogenous distributions of calcite with a grain size of 150600 nm. Thus, LTA 5A zeolite outperforms LTA 4A zeolite with regard to CO2 uptake and the corresponding mechanical properties. This work presents in initial exploration into the application of porous pozzolanic materials in conjunction of CO2 in cement-based materials.

Fluorescence immunoassay based on magnetic separation and ZnCdSe/ZnS quantum dots as a signal marker for intelligent detection of sesame allergen in foods

To detect sesame allergens, a novel fluorescent immunoassay incorporating a magnetic separation step has been developed via two measurement devices: a fluorescence spectrophotometer and a smartphone equipped with a color reader. Sesame allergen monoclonal antibody (Ab) was covalently bonded with quantum dots (QDs) to act as a signal probe. The capture probes were synthesized as sesame allergen (SA) modified carboxyl-functional magnetic polystyrene microspheres (MPMs). Analytical variables such as the amount of modified SA, the reaction volume of the QDs-Ab, the ionic strength, the pH, and the incubation time of the reaction were optimized. The analytical range and the limit of detection (LOD) of the spectrophotometer-based assay were 80–640 μg/L and 12.75 μg/L, respectively. The analytical range and the LOD with smartphone read-out were 80–640 μg/L and 10.15 μg/L, respectively. Furthermore, the developed assay using the fluorescence spectrophotometer and the smartphone read-out was successfully applied to field testing of SA in solution extracts of biscuits, bread, almond beverage, and energy bars with acceptable results. The recovery rates were in the range 89–108%. It was concluded that the new assay may be used for rapid sesame allergen testing in the laboratory and in the field.