Substrate Solution Research Articles

Development of scallion (Allium fistulosum L.) in substrate and homeopathic solutions of water hyacinth

Scallion (Allium fistulosum) is a widely appreciated condiment in the Brazilian population, with significant economic and nutritional importance. Organic cultivation alternatives for this crop have been sought. From this perspective, this study aimed to evaluate the development of scallion in a substrate produced from the floating aquatic plant known as Water Hyacinth (Eichhornia crassipes), combined with soil or without it, with the application of homeopathic solutions. A completely randomized experimental design was used, with five replicates and six treatments, namely: Pure Water Hyacinth Substrate (SAP); Water Hyacinth Substrate with Homeopathic solution (SA+HA); Soil and Water Hyacinth Substrate (S+SA); Soil and Water Hyacinth Substrate with Homeopathic solution (S+SA+HA); Pure Soil (SP), and Soil with Homeopathic solution (S+HA). The following parameters were evaluated 60 days after planting: plant height in centimeters (AP), shoot diameter in millimeters (DP), and the number of shoots (NP). Analysis of variance revealed that plant height (AP) did not exhibit significant differences between substrates with or without the homeopathic solution. In contrast, substrates containing Water Hyacinth exhibited greater shoot diameter and number of shoots. This study showed that the Water Hyacinth substrate and homeopathic solution had promising results in the production of scallion seedlings when combined with soil.

Investigation on mechanism of mechanical activation and chemical reactions in CMP of diamond assisted by hydroxyl free radicals

Chemical mechanical polishing (CMP) is a crucial manufacturing process for diamond substrate applications. However, due to the extremely high hardness and chemical stability of diamond, its CMP efficiency is extremely low. This study aims to achieve microscopic simulation of atomic oxidation removal at the three-phase interface between diamond abrasive particle, diamond substrate, and hydroxyl free radicals (∙OH) aqueous solution. The mechanical activation behavior, microscopic mechanism, and feasibility of elementary reactions in the ∙OH aqueous solution environment was studied using various perspectives of radial distribution function, central atomic coordination state, atomic bonding and removal forms, energy, electron orbitals, and density functional theory (DFT). The simulation results indicate that during the process of diamond atomic oxidation removal, the atomic density at the first adjacent position centered on one atom decreases, and the stable covalent bond structure is disrupted, resulting in an amorphous phase transition. The chemical adsorption reaction generates C-O and C–H bonds. The C atoms mainly separate from the diamond substrate by the forming products such as carbon monoxide (CO), carbon dioxide (CO2), and carbon chains. The mechanical activation behavior indirectly reduces the activation energy of chemical reactions, while increasing the absolute value of adsorption energy and improving the ability of chemical adsorption solution atoms H and O, as well as ∙OH groups. Based on DFT, it has been verified that the intrusion process of ∙OH groups in the elementary reactions involving the typical product C*O2 is an exothermic reaction that can occur spontaneously, and the energy barrier needs to be overcome by the mechanical action of abrasive particles. At the same time, the energetics of the oxidation of diamond C atoms to generate C*O2 have successfully confirmed that the combined action of ∙OH and diamond abrasive particles is expected to achieve efficient oxidation removal and finishing polishing of diamond atoms.

A Mem-dELISA platform for dual color and ultrasensitive digital detection of colocalized proteins on extracellular vesicles

Accurate, multiplex, and ultrasensitive measurement of different colocalized protein markers on individual tumor-derived extracellular vesicles (EVs) and dimerized proteins with multiple epitopes could provide insights into cancer heterogeneity, therapy management and early diagnostics that cannot be extracted from bulk methods. However, current digital protein assays lack certain features to enable robust colocalization, including multi-color detection capability, large dynamic range, and selectivity against background proteins. Here, we report a lithography-free, inexpensive (< $0.1) and ultrasensitive dual-color Membrane Digital ELISA (Mem-dELISA) platform by using track-etched polycarbonate (PCTE) membranes to overcome these shortcomings. Their through-pores remove air bubbles through wicking before they are sealed on one side by adhesion to form microwells. Immunomagnetic bead-analyte complexes and substrate solution are then loaded into the microwells from the opposite side, with >80% loading efficiency, before sealing with oil. This enables duplex digital protein colorimetric assay with beta galactosidase and alkaline phosphatase enzymes. The platform achieves 5 logs of dynamic range with a limit of detection of 10 aM for both Biotinylated β-galactosidase (B-βG) and Biotin Alkaline Phosphatase Conjugated (B-ALP) proteins. We demonstrate its potential by showing that a higher dosage of paclitaxel suppresses EpCAM-positive EVs but not GPC-1 positive EVs from breast cancer cells, a decline in chemo-resistance that cannot be detected with Western blot analysis of cell lysate. The Mem-dELISA is poised to empower researchers to conduct ultrasensitive, high throughput protein colocalization studies for disease diagnostics, treatment monitoring and biomarker discovery.

Facile fabrication method of nanocomposite pore filling ion exchange membrane: Impregnation method using dispersion solution of inorganic particles

Research on composite ion exchange membranes (IEMs) focuses on compensating the limitations of homogenous IEMs. The fabrication of nanocomposite IEMs is relatively complex, as the dispersion of inorganic substances within a polymer matrix must be considered. In this study, we propose a simple method for preparing nanocomposite IEMs by combining a porous substrate and dispersion solution with inorganic nanoparticles. The nanocomposite porous substrate with nanoparticles is prepared by impregnating a solution into a porous substrate, where the nanoparticles penetrate the nanosized pores of the substrates by capillary forces. Subsequently, nanocomposite pore-filling IEMs (PIEMs) are fabricated by impregnating an electrolyte solution into the substrate and photopolymerization. Impregnation applies to the manufacture of nanocomposite PIEMs, regardless of the type, surface conditions, and size of inorganic particles in dispersion. Through the sequential impregnation of dispersion solutions, single- and multi-component PIEMs containing more than one type of nanoparticle are manufactured. The increased interconnectivity of ion conduction channels in PIEMs by nanoparticles causes permselectivity improvement in nanocomposite PIEMs. However, compared to PIEMs without inorganic particles, the addition of inorganic particles results in a lower electrolyte polymer content in the PIEMs, leading to deterioration of the ion exchange capacity and resistance of nanocomposite PIEMs.

Novel Electrocatalytic Hydrogenation Using a Solid Polymer Electrolyte (SPE) Reactor

Organic electrosynthetic reactions, which are driven by electricity, can generally be carried out under mild conditions (room temperature and ambient pressure). In addition, they do not require any hazardous reagents and produce less waste than other conventional chemical syntheses. Therefore, electrosynthesis is known to be a mild and clean method for organic synthesis and there has recently been renewed interest in its development. However, electrosynthesis also has some disadvantages. Ordinary chemical reactions are homogeneous, while the reaction field of electrolysis is a heterogeneous interface, therefore electrosynthesis has a productive drawback. In addition, a large amount of supporting electrolyte is usually required. Therefore, the availability of solvents is limited by the necessity for dissolution of a supporting electrolyte. The presence of the supporting electrolyte might also cause separation problems in the reaction workup. Moreover, in an ordinary electrolysis system, solution resistance is generated between the working and counter electrodes, resulting in a decrease in energy efficiency. To overcome these problems, we focused on a solid polymer electrolyte (SPE) reactor which was originally developed for fuel cell technologies and demonstrated various electrocatalytic hydrogenations in a SPE reactor (Figure 1) [1-5].As shown in Figure 1, a SPE membrane such as a proton exchange membrane (PEM) is integrated into the central part of the reactor, and is sandwiched between a pair of catalyst layers on the anode and cathode sides. For this reason, the substrate solution does not require a supporting electrolyte and the cell resistance can be minimized. The anode and cathode have highly porous 3D structures in order to conduct an efficient electrochemical reaction. Moreover, the reaction can be carried out in a flow operation. Thus, the SPE reactor system possesses many characteristics designed to overcome the disadvantages of conventional electrosynthetic processes.In a series of studies we have conducted, in this presentation, we will discuss two topics such as diastereoselective reduction of cyclic ketones and electrocatalytic hydrogenation of pyridines.The authors gratefully acknowledged support by JST CREST Grant No. 18070940, Japan.[1] A. Fukazawa, M. Atobe, et al. ACS Susutain. Chem. Eng. 2019, 7, 11050.[2] S. Nogami, M. Atobe, et al. J. Electrochem. Soc. 2020, 167, 155506.[3] A. Fukazawa, M. Atobe, et al. Org. Biomol. Chem. 2021, 19,7363.[4] S. Nogami, M. Atobe, et al. ACS Catalysis, 2022, 12, 5430.[5] Y. Shimizu, M. Atobe, et al. ACS Energy Lett., 2023, 8, 1010. Figure 1

Colorimetric aptasensor based on Fe3O4@MOF@Pt nanozymes for ultrasensitive detection of histamine in fish

The accurate determination of histamine in fish is imperative for food safety, given the toxic nature of this biogenic amine. This study presents an innovative colorimetric aptasensor for the ultrasensitive detection of histamine in fish, utilizing nanozymes based on magnetic metal-organic frameworks coated with Pt nanoparticles (Fe3O4@MOF@Pt), which exhibit high peroxidase-like catalytic activity, magnetism, and superior optical properties. The surface of Fe3O4@MOF@Pt nanozymes were modified with DNA strands complementary to the histamine aptamer, creating effective colorimetric probes. In the presence of histamine, these colorimetric probes compete with histamine molecules for aptamer binding on the enzyme plate. Color development is triggered by adding a TMB and H2O2 substrate solution to the enzyme plate. This competitive binding-based aptasensor allows for rapid and accurate histamine quantification within a linear range of 10 pM to 10 μM, and a notable detection limit of 6.23 pM. Furthermore, the sensor demonstrated excellent specificity, distinguishing histamine from l-histidine and other biogenic amines. Tested on mackerel samples, the aptasensor showed spiked recoveries of 91.4%–109.6%, validating its practical applicability. This sensor offers an ultrasensitive, specific, and reusable tool for histamine detection, representing a significant advancement in ensuring the safety of fish products.

IMPROVEMENT OF ELEMENTARY COMPONENT OF DAMAGED SUBSTRATES BY SAPONITE CLAY INCLUSION

In this proposed article, the impact on the elemental composition of sand substrates is determined using the example of the Andriykovetskyi quarry-dump complex and the Barsukivskyi sand pit, which are located in the Central Podillya region in the conditions of the Right-Bank Forest-Steppe. It was determined, that saponite clay contains a significant amount of macro- and micro- elements, and the directions of this use depend on the composition and origin of saponite: in agriculture, in industry, in construction, an application as a sorbent or as meliorant, etc. It is noted that the use of saponite as an ameliorant is an economical and cost-effective method of reclamation, which allows to reduce the burden on the environment caused by the extraction of minerals, pollution of the territory by heavy metals, the conduct of hostilities, etc. General scientific (analysis), statistical (statistical analysis) and laboratory methods (Fourier-transform spectroscopy) were used to assess the qualitative composition of inorganic and organic components of sand-saponite mixtures and to determine saponite clay as a potentially fertile material. To conduct the research, an averaged sample of sand was taken from the Andriykovetskyi quarry and dump complex and from the Barsukivskyi sand pit. For comparison with reference values, a zonal soil sample was taken from undisturbed areas. Saponite from the Tashkiv deposit with a fraction of 0.1 mm was used for sand-saponite mixtures, the ratio of sand substrate to saponite is 70% to 30%. According to the results of the study of the qualitative composition of the inorganic component, it was determined, that saponite has a positive effect on the composition of the sand-saponite mixture in terms of providing plants with nutrients, such as macro- and micro- elements (Mg, K, Na, Cu, Zn, Ca). This confirms the positive effect of saponite on plant growth, which was obtained by us in previous biotesting experiments, and is explained by the fact that the elements of the sand-saponite substrate are available to plants as a result of their transition into the substrate solution. Adding saponite to the substrate of sand pits also increases the content of organic substances, which accelerates the processes of humification and the formation of soil aggregates: humic acid contributes to the bonding of soil particles; carbohydrates sucrose, fructose, glucose and lactose create a nutrient environment for plants; stearates and stearic acid are the main soap components, lauric acid is a foaming catalyst, their presence in sand-saponite mixtures indicates their transition from saponite. When comparing the samples of sand-saponite mixtures of the Andriykovetskyi quarry-dump complex and the Barsukivskyi sand pit, it was concluded that the processes of soil formation began in the substrate of the Andriykovetskyi quarry-dump complex, since the composition of organic matter is greater here.

Recovery of Proteases and Protease Inhibitors from Ganoderma spp. Cultivated in Amazonian Lignocellulose Wastes.

Ganoderma spp. are a great source of bioactive molecules. The production and recovery of bioactive molecules vary according to strain, growth substrate, and extraction solution. Variations in protease and their inhibitors in basidiomata from a commercial strain (G. lingzhi) and an Amazonian isolate (Ganoderma sp.) cultivated in Amazonian lignocellulosic wastes and extracted with different solutions are plausible and were investigated in our study. Basidiomata from cultivation in substrates based on açaí seed, guaruba-cedro sawdust and three lots of marupá sawdust were submitted to extraction in water, Tris-HCl, and sodium phosphate. Protein content, proteases, and protease inhibitors were estimated through different assays. The samples were characterized by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and Fourier transform infrared spectroscopy with attenuated total reflectance (FTIR-ATR). Tris-HCl provided higher protein extraction from Ganoderma sp. and higher caseinolytic, gelatinolytic, and fibrinolytic activity for G. lingzhi cultivated in açaí. Water extracts of Ganoderma sp., in general, exhibited higher trypsin and papain inhibitor activities compared to G. lingzhi. Extracts in Tris-HCl and sodium phosphate showed more intense protein bands in SDS-- PAGE, highlighting bands of molecular weights around 100, 50, and 30 kDa. FTIR spectra showed patterns for proteins in all extracts, with variation in transmittance according to substrate and extractor. Water extract from Amazonian Ganoderma sp. cultivated in marupá wastes are promising as a source of protease inhibitors, while the Tris-HCL extract of G. lingzhi from açaí cultivation stands out as a source of proteases with fibrinolytic, caseinolytic, and gelatinolytic activities.

Emergent Synchronous Volumetric Oscillation in Hierarchically Structured Self-Oscillating Gel Clusters.

Emergent properties accompanying synchronization among oscillators are vital characteristics in biological systems. Belousov-Zhabotinsky (BZ) oscillators are an artificial model to study the emergence and synchronization in life. This research represents a self-oscillating gel system with clusterable properties to experimentally examine synchronous and emergent properties at a fundamental hierarchical level. Incorporating acrylic acid (AAc) moieties within the gel network facilitates cluster formation through hydrogen bonding in an acidic BZ substrate solution. Upon clustering, both homogeneous and heterogeneous gel assemblies─ranging from double to quadruple clusters─exhibit increased and synchronized periods and amplitudes during the BZ reaction. Notably, in heterogeneous clusters, gel units with initially short periods and small volumetric amplitudes display a significant increase, aligning with the lonfger periods and larger amplitudes of other elements within the cluster, an emergent property. This research can pave the way for a better understanding of synchronous and emergent properties in biological oscillators such as cardiomyocytes.

Microgreen vegetables’ production can be optimized by combining the substrate and nutrient solution in a PFAL

Microgreen vegetables are nowadays a popular crop mainly produced hydroponically in controlled environments. In soilless culture, plants are produced using inert substrates with various properties. Besides, all the macronutrients and trace elements necessary for plant growth and development are provided in the form of a nutrient solution. It is possible to achieve similar yield and product quality of microgreens by using different substrates and reducing the input of nutrients. Our aim was to test the effect of three substrates (peat, coco coir, and cannabis mat) and three nutrient solution strengths (0, 50, and 100 %; NS0, NS50, and NS100) on the growth and quality of mustard, radish, and pea grown as microgreens in a plant factory with artificial lighting. As a general rule, cannabis mat and/or NS0 led to considerably decelerated growth of all microgreens. The antioxidant content including the amount of phenolics showed opposite trends compared to the yield of each microgreen. The hydroponic substrate showed species or variety dependency, especially in the phytochemical compounds. To conclude, treatments including NS100, as well as NS50 with peat showed promising results for high yield, relatively high nutritional value, while also saving the most from the use of fertilizers during microgreen vegetable production.

Deep Ultraviolet Light Emitting Diode Based on Aluminum Gallium Nitride

AlGaN-based deep ultraviolet LED has gradually attracted people's attention, because it can be used in sterilization, secret communication and other fields. According to the research report of nearly twenty years, there are still many shortcomings in the external quantum efficiency, internal quantum efficiency and light extraction efficiency of AlGaN-based deep ultraviolet LED. For this reason, researchers have made many efforts at the chip level, including epitaxial and doping technology. In recent years, more and more researchers have studied packaging technology with low light efficiency caused by Fresnel and total reflection. In epitaxial technology, this paper mainly introduces the material selection of substrate and the use of buffer layer. In this paper, the most commonly used substrate selection and the existing problems and solutions of substrates are summarized. The current process of buffer layer is also introduced. On the doping level, the present situation and development of N-type doping and P-type doping are introduced respectively. The use of the latest doping elements is introduced in this paper. Packaging technology explains the choice between organic materials and inorganic materials, and how the packaging structure can avoid the reflection loss of light to the maximum extent. Finally, the article predicts the future development direction.

Isomerization of maltose to maltulose by microwave heating, using arginine as a catalyst

AbstractMicrowave heating was applied to isomerize maltose to maltulose, using arginine as a catalyst. The initial molar ratio of arginine/maltose was kept constant at 0.05. Maltulose yields of 0.28–0.30 were achieved within 90–400 s, dependent on the microwave power and the volume of the substrate solution but not on the initial concentration of maltose, indicating that isomerization of maltose by microwave heating is highly productive. Independent of the power of the microwave oven and the volume of the substrate solution, the fraction of remaining maltose, the yield of maltulose, the pH of the reaction mixture, and its absorbance at 280 and 420 nm could be expressed as a function of energy density, which was defined as the amount of energy absorbed per unit volume of the reaction mixture. This indicates that the operating conditions for the isomerization of maltose to maltulose by microwave heating can be determined based on the energy density.Practical applicationsIsomerization of aldose saccharides to their rare keto‐isomers in the presence of arginine in a heated aqueous solution is a green and effective process. To further improve the process efficiency, microwave heating can be employed. This study also demonstrated that a so‐called “energy density” can be used to determine the operating condition for the isomerization of sugar by microwave heating.

The Pour-through Procedure Preferentially Extracts Substrate Solution from the Bottom of the Container in Conventional and Stratified Substrates

Due to the widespread use of the pour-through extraction procedure in horticultural production and research, the objective of this study was to determine if the method is biased by preferentially extracting substrate solution near the bottom of the container in both conventionally filled containers as well as intentionally stratified containers. Eight treatments were created using 2.5-L, 17.5-cm tall plastic nursery containers. The first four treatments were created by layering a conventional pine bark substrate (CONV) that was either amended (+A) or nonamended (−A) with fertilizer and lime with the following layers: amended substrate throughout the entire container profile (+A/+A); amended substrate in the top half (top 8.5 cm) over nonamended substrate in the bottom half of the container profile (+A/−A); nonamended substrate in the top half over amended substrate in the bottom half (−A/+A); and nonamended substrate throughout the profile (−A/−A). An additional four treatments were created by intentionally stratifying (STRAT) a fine pine bark substrate (FINE) over a coarse pine bark substrate (CRSE) with the same amendment combinations of +A or −A. On 0 and 42 d after potting, substrate pH and electrical conductivity (EC) were determined on samples collected by the pour-through procedure and 1:1 water extracts of the top and bottom layers in the container. At 42 d after potting, nutrient ions (NO3−, PO42−, K, Ca, Mg, and SO42−) were also measured in both pour-through and 1:1 water extracts of the top and bottom layers. At both dates and in both CONV and STRAT containers, pour-through substrate pH and EC more closely reflected those measurements in the bottom half of the container as determined by the 1:1 water extract. At 42 d after potting, nutrient ions determined by the pour-through procedure were more highly correlated to the 1:1 water extracts from the bottom half of the container compared with the top half of the container in both CONV and STRAT substrates. Evidence herein demonstrates that the pour-through procedure is more reflective of the lower half of the container than the upper half for both CONV and stratified substrates.

An electropneumatic cleaning device for piezo-actuator-driven picolitre-droplet dispensers.

Recently, we introduced the liquid application method for time-resolved analyses (LAMA). The time-consuming cleaning cycles required for the substrate solution exchange and storage of the sensitive droplet-dispenser nozzles present practical challenges. In this work, a dispenser cleaning system for the semi-automated cleaning of the piezo-actuator-driven picolitre-droplet dispensers required for LAMA is introduced to streamline typical workflows.

Electrochemical immunosensors for 2,4-dichlorophenoxyacetic acid based on 3-aminopropyltrimethoxysilane modified electrodes

A novel electrochemical immunosensor prepared by direct coating of small molecular hapten on glassy carbon electrode (GCE) is reported for the detection of 2,4-dichlorophenoxyacetic acid (2,4-D). The glassy carbon electrodes were activated by electrochemical method and then were further treated with 3-aminoprpyltriethoxysilane (APS) to functionalize the GCE surface with amino groups for covalent linkage to small molecular hapten of 2,4-D with carboxyl groups. The electrodes were characterized by X-ray photoelectron spectroscopy (XPS). The principle of this immunoassay is based on an indirect competitive immunoassay. Analytes of 2,4-D and hapten of 2,4-D immobilized on glassy carbon electrode (GCE) compete for 2,4-D antibodies labeled by horseradish peroxidase (HRP-anti-2,4-D). After complete immunoreaction, the GCE attached HRP-anti-2,4-D tracers was transferred to a substrate solution containing hydroquinone (QH2) and hydrogen peroxide for square wave voltammetry (SWV) detection. Determination conditions were optimized. The SWV anodic peak current decreased linearly with the increase of 2,4-D concentration over the range from 0.10 to 15.0 mg/L 2,4-D with a detection limit of 0.01mg/L. The performance of this electrochemical immunoassay was successfully evaluated with river water spiked with 2,4-D, indicating that this convenient, rapid, and sensitive technique offers great prospect for the monitoring of trace 2,4-D in environment.

Highly sensitive electrochemical immunosensor based on SiO2 nanospheres for detection of EGFR as colorectal cancer biomarker

Colorectal cancer is one of the most common cancers, and its incidence rate keeps increasing worldwide. Epidermal growth factor receptor (EGFR) is highly expressed in colorectal cancer cells, and its activation leads to the activation of downstream kinase pathways to promote cell growth, resulting in tumour growth and progression. EGFR is expressed in only small amounts in normal cells, however, it is overexpressed in tumour cells and is a potential tumour marker, thus the detection of which is of great importance. This work proposes a novel and highly sensitive electrochemical immunosensor based on nucleic acid aptamer recognition and silver deposition for EGFR detection. The key novelty of this work is the use of SiO2 nanospheres to enhance the sensitivity. First, SiO2 nanospheres were synthesized and modified on the surface of a gold electrode using a self-assembly process. This provided a large surface area to allow high loading of capture antibodies. The antibody was then immobilized on the SiO2 nanosphere modified electrode surface to form an immunosandwich complex with the antigen and biotin-labelled nucleic acid aptamer. Afterwards, the affinity-labelled alkaline phosphatase was immobilized onto the electrode with the specific reaction of biotin and affinity. The obtained product was subjected to silver deposition in the substrate solution. The large surface area provided by the SiO2 nanospheres allowed significantly improved sensitivity. Experiments were performed to optimize the concentration of immobilized antibodies and biotin-labelled nucleic acid aptamer. The experimental results show a good linearity of EGFR concentration in the range of 1 to 1000 ng/mL, with the lowest detection limit up to 0.06 ng/mL. This method has high sensitivity and stability, which allows it to have a broad application prospects in the clinical field.

Enzymatic Assay of Immobilized β-D-Galactosidase Enzyme on Magnetite Nanoparticle

According to the high operational costs, low stability, and reusability of enzymes, immobilization by nanoparticle gathering has increased in recent years. Iron oxide nanoparticles (magnetite nanoparticles, Fe₃O₄) have been prepared by mixing one volume of iron dioxide ions and two volumes of iron trioxide ions with HCl via the precipitation of iron salts by NH₄OH. The features of magnetic nanoparticles have been studied by Atomic Force Microscopy (AFM), X-Ray Diffraction (XRD), Fourier Transform Infrared Spectroscopy, and Scanning Electron Microscopy (SEM). The prepared Fe3O4 was used in the adsorption method to immobilize the galactosidase enzyme. The immobilized enzyme has been compared with the crude one by optimizing time, PH, temperature, substrate solution concentration, and enzyme solution concentration. As a result, the immobilized enzyme has exhibited higher activity over long storage times, and a wide PH and temperature range than crude enzyme. In addition, whatever the substrate and enzyme concentrations, the activity of the immobilized enzyme increased over the non-immobilized one. As a result, a lower Km value for immobilized D-galactosidase indicates a higher affinity for the substrate than crude D-galactosidase.

Physicochemical properties of clayey deposits slurry treated by lime-activated ISSA and GGBS considering seawater salinity effect

This study sheds light on the engineering and environmental performance of lime-activated incinerated sewage sludge ash (ISSA) and ground granulated blast furnace slag (GGBS) treated Hong Kong marine deposits (HKMD) slurry by stabilisation/solidification (S/S) technology, which is proposed using as fill materials in reclamation projects. The S/S performance of the treated HKMD with distilled water and seawater under different salinities was investigated. The results show that seawater could help S/S treated HKMD gain strength by using activated industrial wastes (ISSA and GGBS). The hydration and pozzolanic reactions between ISSA, GGBS, CaO and clayey compositions in HKMD make contributions to the strength development, porosity decrease and heavy metals stabilisation, which is supported by the characterization analysis including thermo-gravimetric (TG) analysis, mercury intrusion porosimetry (MIP) tests, nitrogen adsorption/desorption isotherms (NAI), scanning electron microscopy coupled with energy-dispersive spectrometry (SEM-EDS) and the leaching test of toxicity characteristic leaching procedure (TCLP). Seawater of 1.8% salinity (18 g/kg) is better than the distilled water and seawater of 3.6% salinity as a substrate solution in the S/S treated HKMD, because of the highest unconfined compressive strength and lowest porosity in the treated samples. The highest pH may account for its highest strength under the 1.8% salinity conditions. The S/S process could effectively stabilize the contaminants regardless of the curing time and the salinity of the mixing solution, and the leachates from the stabilized HKMD are environmentally safe and meet the requirement of standard in Hong Kong on the recycling treated soil. Therefore, recycling wastes—ISSA and GGBS with lime can be used as an appealing binder to stabilize/solidify marine deposits as environmental-friendly reusable materials in reclamation projects.

Start Up And Operation Of A UASB Rector With Molasses As A Preferred Substrate – A Case Study

Anaerobic digestion followed by aerobic treatment has gained wide acceptability for many of the wastewater treatment. Several novel bio-reactors have been developed. All these reactors pose a problem of shock loading, when the high COD organic industrial waste is fed in to the reactor. Further, the normal substrates like glucose, sewage, citric acid may result in addition of a large volume of the substrate solution for a given organic loading. Both these problems are solved by adopting molasses, a typical by-product from the sugar industry. Among the bio-reactors to treat high strength waste waters, the Up-flow Anaerobic Sludge Blanket Reactor (UASBR), has received wide popularity for the treatment of domestic waste waters as well as for a variety of industrial wastewaters. This paper is to present a cogent and a clear picture of the startup and steady state operation of an UASB Reactor with molasses as the initial startup substrate for the development of well settleable sludge granules, the major feature of an UASB Reactor. The UASB reactor was fabricated in transparent Plexiglas. The reactor had a working volume of 9.75 liters with provision of ports for input, output, collection of samples, and collection of gas. Inside the settler, a gas-liquid-solid separation system using a glass funnel and a gas pressurizing plexiglass tube was provided. The aim was to granulate the sludge and acclimatizing it completely to take high organic loading. The feed was supplemented with a fixed COD: N: P ratio by adding urea for nitrogen and KH2PO4 for phosphorous. The HRT was fixed to be 8 hours. The reactor temperature was maintained at 35 ± 20oC. In about 55 days, the buttery seed sludge got granulated at an OLR of 8 g COD/l.day. The SEM of the granules exhibited a mixed morphology on the surface of the granules while filamentous Methanothrix proliferation could be clearly seen in the interior of the granule. Methanoceata and Methanothrix are the two dominant species found in the granules.

Simple performance of the planar SOS-Umu-C–FLD genotoxicity bioassay shown for perfume and packaging material analysis

Planar bioassays are powerful, sustainable tools for nontargeted detection of hazardous compounds in complex samples. They provide more information on a sample than corresponding in vitro assays and are more sustainable in terms of plastic material and solvent consumption. However, instrument investment costs for high-performance thin-layer chromatography are high. Hence, the question arose of whether the sophisticated sensitive planar genotoxicity bioassay could be performed manually without instrumentation under simple conditions. Cheaper plate types were studied as well as manual application of the samples, cell suspension, and substrate solution. As a result, genotoxic compound zones were detected as rose-colored or orange fluorescent resorufin end-product formed upon contact of the genotoxins in tested perfume and packaging materials with a genetically modified Salmonella Typhimurium strain. The simple performance was found to be possible for low sample application volumes. Knowledge on neutral pH value and thickness of the adsorbent layer were further key aspects. Manual spraying was found to be superior to manual immersion if excess liquid was avoided. For high sample volumes and a higher level of standardization, the open-source 2LabsToGo system was proposed as excellent option for low investment costs. Its very low instrumental footprint and the straightforward prioritization strategy help analytical chemistry to balance between technology and nature/ecology to reduce the instrumental footprint and planetary overshoot.