•Cross-linking can increase stability of chitosan but may decrease adsorption capacity.•Complexation is the main mechanism via which chitosan functions as an adsorbent.•Combining with magnetic ...particles with adsorbent can simplify regeneration process.•Desorption of metal ions from chitosan based adsorbents can be achieved via acidic treatment.•Chitosan based adsorbents can be used efficiently in packed bed columns.
Chitosan, a low cost polymer, has been used in many studies for adsorption of heavy metal ions. This review covers the performance of all those adsorbents which were derived from chitosan for the adsorption of heavy metal ions in recent past. Further, the common chitosan modifications methods have been discussed in this paper among which crosslinking and grafting were found to be the most popular methods. Adsorption equilibrium and kinetics were also studied and Pseudo-second order kinetic model and Langmuir isotherm were found to be successful for modeling of most of the chitosan derivatives-metal adsorption experiments. Moreover, with focus on chitosan derivatives, effect of adsorbent structure on metal removal, adsorption mechanism, effect of co-existing ions on adsorption, adsorbent synthesis protocols and regeneration methods have been also discussed in great detail. Finally, fixed bed column design for industrial wastewater treatment was elaborated along with efficiency of chitosan based adsorbents in columns.
Gas separation processes are amongst the most important operations in the refineries and gas-related industries. Recently, many efforts are being dedicated towards modifying the gas separation ...properties of existing polymers to further expand their use for extensive industrial gas separation applications. Mixed matrix membranes (MMMs), which are organic–inorganic hybrid membranes, have been proposed as the alternative approach to intensify the comprehensive gas separation performance of the polymeric membranes. In this regard, we analyze and review the recent scientific and technological advances in the development of MMM's, including the emerging class of inorganic fillers like two-dimensional (2D)materials, that have been the focus of much recent work for gas separation. The review also discusses the current issues associated with the filler materials and further provides an outline to overcome the emerging challenges for the future development of high performance MMMs.
•Reviewed recent advances of inorganic materials used to develop MMMs for gas separation.•Highlighted 2D materials as emerging membranes platform for gas separation.•Modification in the polymer matrix and polymer-filler interaction in MMM.•Effect of filler loading on gas permeation.
•We conducted a quantitative and qualitative review on YOLO application in agriculture.•YOLO modification and integration were discussed to solve task-specific challenges.•YOLO-based tools and ...technologies show potential for agricultural task automation.•This detailed documentation will advance existing knowledge on YOLO in agriculture.•The study will benefit the multidisciplinary agricultural community.
Vision is a major component in several digital technologies and tools used in agriculture. Object detection plays a pivotal role in digital farming by automating the task of detecting, identifying, and localization of various objects in large-scale agrarian landscapes. The single-stage detection algorithm, You Only Look Once (YOLO), has gained popularity in agriculture in a relatively short span due to its state-of-the-art performance in terms of accuracy, speed, and network size. YOLO offers real-time detection performance with good accuracy and is implemented in various agricultural tasks, including monitoring, surveillance, sensing, automation, and robotics operations. The research and application of YOLO in agriculture are accelerating at a tremendous speed but are fragmented and multidisciplinary in nature. Moreover, the performance characteristics (i.e., accuracy, speed, computation) of the object detector influence the rate of technology implementation and adoption in agriculture. Therefore, this study aimed to collect extensive literature to document and critically evaluate the advances and application of YOLO for agricultural object recognition tasks. First, we conducted a bibliometric review of 257 selected articles to understand the scholarly landscape (i.e., research trends, evolution, global hotspots, and gaps) of YOLO in the broad agricultural domain. Secondly, we conducted a systematic literature review on 30 selected articles to identify current knowledge, critical gaps, and modifications in YOLO for specific agricultural tasks. The study critically assessed and summarized the information on YOLO’s end-to-end learning approach, including data acquisition, processing, network modification, integration, and deployment. We also discussed task-specific YOLO algorithm modification and integration to meet the agricultural object or environment-specific challenges. In general, YOLO-integrated digital tools and technologies showed the potential for real-time, automated monitoring, surveillance, and object handling to reduce labor, production cost, and environmental impact while maximizing resource efficiency. The study provides detailed documentation and significantly advances the existing knowledge on applying YOLO in agriculture, which can greatly benefit the scientific community. The results of this study open the door for implementing YOLO-based solutions in practical agricultural scenarios and add to the expanding corpus of information on computer vision applications in agriculture.
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•Coconut shell nanoparticles were prepared from wet stirred media milling.•Parameters including feed-size and surfactant concentration were optimized.•Particle size was decreased up ...to a certain milling time, after which it increased.•Particle Size Analyzer, XRD and TEM confirmed presence of nanoparticles.•FTIR confirmed retention of chemical composition in nanoparticles.
Coconut shell nanoparticles have been prepared via top-down approach from wet-stirred media mill. Milling parameters like milling time, feed concentration, effect of surfactants and surfactant concentration have been investigated for efficient production of nanoparticles. Particle size of nanoparticles was estimated from Particle Size Analyzer and chemical composition of raw and nanosized Coconut Shell Particles (CSPs) was analysed from Fourier Transform Infrared Spectroscopy. Particle size of nanoparticles was confirmed from Transmission Electron Microscopy (TEM), which also revealed the spherical morphology of the nanoparticles. X-Ray Diffraction patterns reflected presence of constituents of CSPs and crystallite size derived from it was comparable with the one obtained from TEM images. The work proposes an improvised and effective process of mechanical preparation over dry ball milling method to prepare nanoparticles.
The core objective of nanoparticles is to control and manipulate biomacromolecular constructs and supramolecular assemblies that are critical to living cells in order to improve the quality of human ...health. By definition, these constructs and assemblies are nanoscale and include entities such as drugs, proteins, DNA/RNA, viruses, cellular lipid bilayers, cellular receptor sites and antibody variable regions critical for immunology and are involved in events of nanoscale proportions. The emergence of such nanotherapeutics/diagnostics will allow a deeper understanding of human longevity and human ills that include cancer, cardiovascular disease and genetic disorders. A technology platform that provides a wide range of synthetic nanostructures that may be controlled as a function of size, shape and surface chemistry and scale to these nanotechnical dimensions will be a critical first step in developing appropriate tools and a scientific basis for understanding nanoparticles.
In the present work, the discrete element method (DEM) is used to investigate the behaviour of Rosin-Rammler (R-R) particle size distribution (PSD) during hopper discharge. The study attempts to ...identify mass flow rate (MFR) and segregation as a function of spread parameter (PSD width) and location parameter, which includes detailed analysis of bulk density, segregation and velocity profile of particles. The applicability of the widely used Beverloo correlation for prediction of MFR for studied R-R PSDs is also investigated. The results show that, (1) MFR increases as PSD width (at fixed location parameter) increases, whereas MFR decreases with increase in location parameter at fixed PSD width; (2) the studied R-R PSDs exhibit a monotonic trend of flow bulk density and MFR with respect to PSD width and location parameter; (3) the effect of PSD width on overall segregation is found to be more than the location parameter; (4) the velocity profiles for considered R-R PSDs vary along the height of hopper, but remain uniform in shape and follow a pure parabolic increase from the hopper wall; (5) DEM flow rate prediction shows a good agreement with the Beverloo correlation by applying the concept of flow bulk density.
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•Discharge behavior of Rosin-Rammler particle-size distributions was studied by DEM.•Flow rate increases as PSD width increases and decrease with location parameter.•The PSD width affects segregation more than location parameter for considered PSDs.•The velocity profile of Rosin-Rammler PSDs represents typical parabolic nature.•DEM mass flow rate prediction shows a good agreement with the Beverloo correlation.
Increasing concerns on global warming and climate change have led to numerous attempts on developing new membrane materials to reduce excessive CO2 emission into the atmosphere. In the present work, ...we focused on the separation of CO2 from gas mixtures through two-dimensional (2D) materials based mixed matrix membranes (MMMs). The ionic liquid (IL) 1-Ethyl-3methylimidazolium bis (trifluoromethylsulfonyl) imide together with different weight fractions (0.5–1.5 wt %) 2D materials, such as molybdenum disulfide (MoS2) and hexagonal boron nitride (h-BN), were homogenously blended to prepare polyether sulfone (PES) MMMs. The main aim was to investigate the effect of the addition of 2D materials on the gas separation/permeation properties of the PES membranes. Pure gas permeation for N2, CO2, and CH4 and binary gas mixtures separation for CO2/N2 and CO2/CH4 were investigated through pure PES and modified PES membranes. The prepared membranes were characterized by Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA) and water contact angle tests. The gas permeabilities were found to be improved by average 15–20 times higher compared to pure PES. The αCO2/CH4 and αCO2/N2 were improved up to 124% and 18% using PES/h-BN (1 wt %)/IL and PES/MoS2 (1.5 wt %)/IL combination, respectively. In overall, 2D materials and IL together as a filler into PES matrix revealed a significant improvement in the gas separation/permeation properties of PES and can be considered as a competent membrane for CO2/CH4 and CO2/N2 separation.
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•CO2/N2 and CO2/CH4 separation performance of polyethersulfone (PES) was improved by embedding 2D materials and ionic liquid (IL) in its matrix.•2D materials used are hexagonal boron nitride (h-BN) and molybdenum disulfide (MoS2).•Ionic liquid used is 1-Ethyl-3methylimidazolium bis (trifluoromethylsulfonyl) imide.•Prediction of gas transport properties in MMM using Aspen Plus.•2D materials and IL together as a fillers into PES matrix revealed a significant improvement in the gas separation/permeation properties of PES.
In the present study, we have synthesized novel dihydropyrimidines (
1a–
j), their dimethylated adducts (
2a–
j), and hydrazine derivatives (
3a–
j) of
2a–
j and subsequently their pyrazole ...derivatives (
4a–
j). Elemental analysis, IR,
1H NMR and mass spectral data elucidated structure of newly synthesized compounds. Some of these novel derivatives showed moderate to potent in vitro antioxidant, anti-inflammatory, antibacterial, antifungal and anthelmintic activity.
Synthesis of pyrimidine derivatives and its pyrazole derivatives. Few of the synthesized compounds shows potent antioxidant, anti-inflammatory, antibacterial, antifungal and anthelmintic activities.
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► Synthesis of novel dihydropyrimidines and its pyrazole derivatives. ► Structural elucidation with elemental analysis, IR,
1H NMR and mass spectral data. ► Some of the compounds proved good antioxidant, anti-inflammatory, antimicrobial and anthelmintic activity.
Herein we are reporting a base-catalysed carbanion formation of N-methyl-4-piperidone (NMPi) and thermoset anion exchange membrane thereof. N-methyl-4-piperidone (NMPi) was reacted with formaldehyde ...in presence of sodium hydroxide to obtain NMPi-formaldehyde based prepolymer. An anion exchange membrane (AEM) was obtained by grafting prepolymer on to polyvinyl alcohol (PVA) by thermal annealing followed by quaternization. By varying the NMPi/PVA ratio, four AEMs namely M1-M4 was synthesized. Detailed physicochemical, microscopic, thermal and dimensional stability studies were performed to assess their applicability. AEMs were explored for acid recovery from hydrochloric acid (HCl), sulphuric acid (H2SO4), acetic acid (CH3COOH), simulated feed (2 M HCl containing 6% FeSO4) and effluent from a local bentonite mine (acid concentration ∼8 M) by diffusion dialysis. Proton dialysis coefficient (UH+) of 22 × 10−3 m h−1, Fe2+ dialysis coefficient (UFe2+) of 1.94 × 10−5 m h−1 and separation factor (S) of 112 units for best performing membrane was obtained for simulated feed. Acid recovery of 80% was achieved in 50 h from effluent obtained from local bentonite mine by changing the permeate side thrice at diffusion equilibrium; encouraging its best applicability and stability in highly acidic environment.
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•Robust thermoset anion exchange membrane.•Excellent stability in ∼8 M acid concentration of local bentonite mine waste.•Dialysis coefficient of 22 × 10−3 m h−1 for simulated solution.•Acid recovery of 80% from acid effluent.
All living things, including plants, animals, and humans, need water in order to live. Even though the world has a lot of water, only about 1% of it is fresh and usable. As the population has grown ...and water has been used more, fresh water has become a more valuable and important resource. Agriculture uses more than 70% of the world’s fresh water. People who work in agriculture are not only the world’s biggest water users by volume, but also the least valuable, least efficient, and most subsidized water users. Technology like smart irrigation systems must be used to make agricultural irrigation more efficient so that more water is used. A system like this can be very precise, but it needs information about the soil and the weather in the area where it is going to be used. This paper analyzes a smart irrigation system that is based on the Internet of Things and a cloud-based architecture. This system is designed to measure soil moisture and humidity and then process this data in the cloud using a variety of machine learning techniques. Farmers are given the correct information about water content rules. Farming can use less water if they use smart irrigation.
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