Browsing by Author "Satish Kumar Verma"

Now showing 1 - 20 of 24

Carbon nanotubes for CO2 capture and conversion
(Elsevier, 2022) Satish Kumar Verma; Prashant Tripathi; Ashish Bhatnagar
It is now generally accepted that carbon emissions from the burning of fossil fuels and changes in land use are causing atmospheric CO2 levels to rise rapidly, resulting in an increase in the impact of greenhouse gases (GHGs) due to climate change. Carbon Capture and Storage and later on conversion to a valuable fuel by adsorption in carbon nanomaterials is an attractive approach to mitigate future global climate change and is generally accepted as a viable road to sustainable fossil fuel usage. Out of the various carbon nanomaterials, carbon nanotubes (CNT) are the front-running candidates owing to their classical performance as adsorbents. CNTs are pure carbon cylinders with a radius of a few nm and variable lengths (100nm to mm). CNTs are extraordinarily light and highly porous and very suitable for gas storage applications due to their high surface area. CNTs also have elevated conductivity (thermal and electrical) and are rich in chemistry. The properties mentioned above make them a competent candidate for CO2 adsorption and desorption, efficiently and selectively. This chapter will discuss the state-of-the-art CNTs used for carbon capture and prospects of the same. © 2023 Elsevier Inc. All rights reserved.
Catalytic characteristics of titanium-(IV)-isopropoxide (TTIP) on de/re-hydrogenation of wet ball-milled MgH2/Mg
(John Wiley and Sons Ltd, 2022) Sunita Kumari Pandey; Satish Kumar Verma; Ashish Bhatnagar; Thakur Prasad Yadav
Magnesium hydride (MgH2) has received much attention as a solid-state hydrogen storage material worldwide due to its high hydrogen storage capacity, good reversibility, and low cost. However, its practical application has been limited due to its high thermodynamic stability and slow kinetics. In the present work, we have employed a new type of catalyst, Titanium-tetra-isopropoxide (TTIP) (Ti(OC3H7)4), to catalyze MgH2. To disperse the catalyst evenly over the MgH2, the milling operation was conducted using tetrahydrofuran (THF) as a process control agent. Here, using THF as the process control agent during the wet ball milling along with TTIP of MgH2 itself used to improve the de/re-hydrogenation behavior of MgH2. A de/re-hydrogenation investigation demonstrates that MgH2 catalyzed by TTIP has better hydrogen storage properties (onset dehydrogenation temperature 210°C) than as-cast MgH2 (onset dehydrogenation temperature ~400°C). Furthermore, a remarkable catalytic behavior of TTIP on MgH2 was observed during de-/re-hydrogenation kinetics (absorb the hydrogen ~4.6 wt% within the 1.5 minutes at a temperature of 300°C under a hydrogen pressure of 20 atm and release the hydrogen of ∼4.98 wt% within 5 minutes at ∼300°C) due to formation of intermediate compound Mg1−xTixO, and it retains nearly constant hydrogen storage capacity (from 5.25 to 5.20 wt% in rehydrogenation and from 4.95 wt % to 4.95 wt% in dehydrogenation) up to 60 cycles of de/re-hydrogenation. The estimated desorption activation energy for MgH2-TTIP using Arrhenius equation is 77.67 kJ/mol. The reason for de/re-hydrogenation kinetics improvement of MgH2-TTIP can be seen in the mechanism. © 2022 John Wiley & Sons Ltd.
Editorial: Seed Microbiome Research
(Frontiers Media S.A., 2022) Wilfried Jonkers; Pedro E. Gundel; Satish Kumar Verma; James Francis White
[No abstract available]
Enhanced hydrogen absorption and desorption properties of MgH2 with graphene and vanadium disulfide
(Elsevier Ltd, 2023) Satish Kumar Verma; Mohammad Abu Shaz; Thakur Prasad Yadav
Magnesium hydride (MgH2) is the most prominent carrier for storing hydrogen in solid-state mode. However, their slow kinetics and high thermodynamics become an obstacle in hydrogen storage. The present study elaborates on the catalytic effect of graphene (Gr) and vanadium disulfide (VS2) on MgH2 to enhance its hydrogen sorption kinetic. The temperature-programmed desorption study shows that the onset desorption temperature of MgH2 catalyzed by VS2 and MgH2 catalyzed by Gr is 289 °C and 300 °C, respectively. These desorption temperatures are 87 °C and 76 °C lower than the desorption temperature of pristine MgH2. The rapid rehydrogenation kinetics for the MgH2 catalyzed by VS2 have been found at a temperature of 300 °C under 15 atm H2 pressure by absorbing ∼4.04 wt% of hydrogen within 1 min, whereas the MgH2 catalyzed by Gr takes ∼3 min for absorbing the same amount of hydrogen under the similar temperature and pressure conditions. The faster release of hydrogen was also observed in MgH2 catalyzed by VS2 than MgH2 catalyzed by Gr and pristine MgH2. MgH2 catalyzed by VS2 releases ∼2.54 wt% of hydrogen within 10 min, while MgH2 catalyzed by Gr takes ∼30 min to release the same amount of hydrogen. Furthermore, MgH2 catalyzed by VS2 also persists in the excellent cyclic stability and reversibility up to 25 cycles. © 2022 Hydrogen Energy Publications LLC
Facile synthesis of M2(m-dobdc) (M = Fe and Mn) metal-organic frameworks for remarkable hydrogen storage
(John Wiley and Sons Inc, 2022) Satish Kumar Verma; Mohammad Abu Shaz; Thakur Prasad Yadav
Metal-organic frameworks (MOFs) are emerging as promising candidates for hydrogen storage material because of their porosity and adjustable hydrocarbon structures coordinated with the metal element. Present work explore the synthesis of M2(m-dobdc) (M = Fe and Mn; m-dobdc4− = 4,6-dioxido-1,3-benzenedicarboxylate) metal-organic frameworks via solvothermal method for the purpose of hydrogen storage application. The X-ray diffraction, transmission electron microscope, scanning electron microscope, energy dispersive X-ray analysis, and nuclear magnetic resonance spectroscopic studies have been done to ensure the synthesized material is M2(m-dobdc) (M = Fe and Mn) MOFs. The Brunauer-Emmett-Teller (BET) analysis reveals the average pore size of 36.271 nm for Mn2(m-dobdc) MOF whereas the average pore size for fe2(m-dobdc) MOF was found to be 2.1992 nm. The as-prepared MOF samples are in the mesoporous range based on pore size distribution (internal pore diameter greater than 2 nm) with spherical pore geometry. Hydrogen storage studies shows that Fe2(m-dobdc) has a hydrogen storage capacity of 0.18 wt% at ambient temperature (30°C) under 100 atm H2 pressure, whereas the hydrogen storage capacity for Mn2(m-dobdc) is 1.38 wt% under identical conditions of temperature and pressure. The hydrogen storage capacity at liquid nitrogen temperature (−196°C) under 100 atm H2 pressure for Fe2(m-dobdc) and Mn2(m-dobdc) is 4.31 and 8.21 wt%, respectively. © 2022 John Wiley & Sons Ltd.
In-situ copper and nickel incorporation in carbon aerogels for efficient hydrogen storage
(Elsevier Ltd, 2025) Pargai Neema; Ashish Bhatnagar; Satish Kumar Verma; Mohammad Abu Shaz
Transition metal-doped carbon aerogels are emerging as promising materials for hydrogen storage due to their adjustable porosity, enhanced chemical functionality, and high specific surface area. In this study, we have synthesized copper and nickel-doped carbon aerogels by in-situ doping, utilizing copper nitrate and nickel nitrate as dopants during the polymerization of resorcinol and formaldehyde using triethylamine to aid the polymerization. The synthesized pristine and chemically activated doped carbon aerogels exhibited specific surface areas of 452 m2/g and 1200 m2/g, respectively. They demonstrated hydrogen storage up to 4.93 wt% and 5.94 wt% under 22 atm pressure at liquid nitrogen temperature, respectively. The study also reveals that increasing specific surface area does not necessarily guarantee proportional increases in hydrogen uptake. Based on electron microscopy and XPS studies, it can be concluded that the balance between specific surface area, pore size distribution, and chemical functionality is critical for optimizing hydrogen storage. © 2025 Hydrogen Energy Publications LLC
Indole-based polymer and its silver nanocomposite as advanced antibacterial agents: Synthetic path, kinetics of polymerization and applications
(2013) Ambika Srivastava; Pooja Singh; Rajesh Kumar; Satish Kumar Verma; Ravindra Nath Kharwar
Atom transfer radical polymerization of 1-allylindole-3-carbaldehyde (AIC) was studied by employing 2-bromoisobutyryl bromide as initiator in toluene. It led to controlled radical polymerization of AIC, with an increase of molecular weight along with the conversion of the monomer, and a relatively narrow molar mass distribution was obtained, as determined by gel permeation chromatography. The living nature of poly(1-allylindole-3-carbaldehyde) (PAIC) was confirmed by the chain extension polymerization whereas 1H NMR analysis showed that the major population of PAIC retained the chain-end functional group. PAIC and its silver nanocomposite were found to be biologically active against some tested bacterial pathogens. Minimum inhibitory concentration tests revealed that PAIC exhibited antibacterial activity against Staphylococcus aureus, Proteus mirabilis and Klebsiella pneumonae whereas PAIC/Ag nanocomposite showed antibacterial activity against Enterococcus faecalis and K. pneumonae. © 2012 Society of Chemical Industry.
Introducing 2D layered WS2 and MoS2 as an active catalyst to enhance the hydrogen storage properties of MgH2
(Elsevier Ltd, 2024) Satish Kumar Verma; Mohammad Abu Shaz; Thakur Prasad Yadav
The current work describes how 2D layered materials, such as MoS2 and WS2, might improve the de/re-hydrogenation kinetics of MgH2. In the presence of WS2 catalyst, desorption of MgH2 begins at 277 °C, with a hydrogen storage capacity of 5.95 wt%, while the onset desorption temperature of MgH2 catalyzed by MoS2 is 330 °C. In just 1.3 min at 300 °C under 13 atm hydrogen pressure, the MgH2-WS2 absorbed approximately 3.72 wt% of hydrogen, and in 20 min at 300 °C under 1 atm hydrogen pressure, it desorbed around ∼5.57 wt% of hydrogen. To ensure the cyclic stability up to 25 cycles of de/re-hydrogenation of the catalyzed MgH2, a continuously 25 cycles of dehydrogenation (under 1 atm hydrogen pressure at 300 °C) and rehydrogenation (under 13 atm hydrogen pressure at 300 °C) were carried out. As a result, MgH2-WS2 exhibits superior cyclic stability than MgH2–MoS2. In addition, with the de/re-hydrogenation kinetics, MgH2-WS2 has a lower reaction activation energy (∼117 kJ/mol) than to other catalyzed and pristine samples. Conversely, the thermodynamical parameters, specifically the change in enthalpy of MgH2, are unaffected by addition of these layered WS2 and MoS2 catalysts. © 2024 Hydrogen Energy Publications LLC
Isolation and functional characterization of a fungal plant symbiont Nigrospora sphaerica, associated to Euphorbia hirta L.
(Springer, 2022) Veer Singh Gautam; Jay Hind Nishad; Puja Kumari; Arti Singh; Satish Kumar Verma; Vijay Kumar Sharma; Jitendra Kumar; Ravindra Nath Kharwar
The endophytic fungi are the endosymbiont which play important role in improving host plant fitness and source of plethora of bioactive molecules. Present study includes the assessment of antimicrobial activity, phytochemical analysis and enzymes activity of fungal endophyte EHL2, isolated from leaf tissues of an Indian medicinal plant Euphorbia hirta L. The fungus exhibited the antibacterial and antifungal activities against a broad range of bacterial and fungal pathogens. To the best of our knowledge, this is the first report about the isolation and characterization of endophytic fungus Nigrospora sphaerica (EHL2) recovered from E. hirta L. The minimum inhibitory concentration (MIC) of the crude extract against pathogenic bacteria ranged from 0.45 to 3.14 mg/ml. For antifungal ativity of fungus, the highest percentage of inhibition was observed against Colletotrichum sp. (33.78%) while, minimum activity was noticed against Alternaria solani (16.60%). Preliminary mycochemical analysis revealed the positive tests for alkaloids, phenolics, flavonoids and terpenoids. The results showed that the total phenolic content (TPC) and total flavonoid content (TFC) of crude extracts were 78.11 ± 0.04 mg GAE/g and 235.94 ± 3.06 mg RE/g, respectively. Furthermore, the fungus also produced amylase, cellulase, protease and laccase enzymes. In conclusion, these positive results of mycochemicals and enzymes activity displayed by N. sphaerica of E. hirta provide an opportunity which could be exploited for host protection against pathogens and enzyme production. © 2022, Indian Phytopathological Society.
Mechanistic understanding of the superior catalytic effect of Al65Cu20Fe15 quasicrystal on de/re-hydrogenation of NaAlH4
(Elsevier Ltd, 2023) Satish Kumar Verma; Ashish Bhatnagar; Mohammad Abu Shaz; Thakur Prasad Yadav
The complex hydride NaAlH4 remains the archetype hydrogen storage system. In this paper, we have explored the catalytic action of Al65Cu20Fe15 quasicrystal (QC) on the de/re-hydrogenation study of NaAlH4. The leached ball-milled Al65Cu20Fe15 (LBMACF) catalyzed NaAlH4 sample has shown a lower hydrogen desorption temperature (140 °C) than other catalyzed and uncatalyzed NaAlH4 samples. NaAlH4-LBMACF rapidly absorbed ∼3.20 wt% of hydrogen within 1 min and absorbed maximum capacity (∼4.68 wt%) in 15 min, while NaAlH4-LACF, NaAlH4-BMACF, NaAlH4-ACF, and pristine NaAlH4 absorbed only 0.50 wt%, 1.38 wt%, 1.10 wt%, and 0.70 wt% in 1 min at 130 °C under 100 atm hydrogen pressure. NaAlH4-LBMACF has desorbed ∼4.22 wt% of hydrogen within 15 min, while the same amount of hydrogen desorbed by NaAlH4-LACF takes 45 min at 130 °C under 1 atm hydrogen pressure. NaAlH4-LBMACF shows reversibility up to 25 cycles with minimum degradation of hydrogen storage capacity of ∼0.06 wt% during de/re-hydrogenation. The catalytic mechanism and catalytic effect of Al–Cu–Fe on the NaAlH4 have been discussed using structural, microstructural analysis, in-situ nuclear magnetic resonance (NMR) spectroscopy, in-situ Raman spectroscopy, and X-ray photoelectron spectroscopy (XPS). © 2022 Hydrogen Energy Publications LLC
Microbial biofilm in remediation of environmental contaminants from wastewater: Mechanisms, opportunities, challenges, and future perspectives
(CRC Press, 2022) Pallavi Singh; Akshita Maheshwari; Varsha Dharmesh; Vandana Anand; Jasvinder Kaur; Sonal Srivastava; Satish Kumar Verma; Suchi Srivastava
[No abstract available]
Multiple improvements of hydrogen sorption and their mechanism for MgH2 catalyzed through TiH2@Gr
(Elsevier Ltd, 2020) Satish Kumar Verma; Ashish Bhatnagar; Vivek Shukla; Pawan Kumar Soni; Anant Prakash Pandey; Thakur Prasad Yadav; Onkar Nath Srivastava
The present investigation reports the effect of TiH2 templated over graphene (TiH2@Gr) on the hydrogen sorption characteristics of MgH2/Mg. The as synthesized TiH2@Gr leads to significant effect on sorption in MgH2 by the following effects: the first is dehydrogenation of MgH2–TiH2@Gr, which leads to the conversion of some part of TiH2 into TiH1.924. TiH2 together with TiH1.924 works as a better catalyst than TiH2 alone. The second is ball-milling of TiH2@Gr, which produces defective graphene, which also works as co-catalyst. The third is anchoring of TiH2 on graphene, which does not allow the catalyst to agglomerate. The catalytic effect of TiH2@Gr on MgH2 is found to be better than Ti@Gr and TiO2@Gr. The onset desorption temperature for MgH2–TiH2@Gr is ~204 °C, which is 31 °C and 36 °C lower than MgH2–Ti@Gr, MgH2–TiO2@Gr respectively. The better catalytic behavior of TiH2@Gr also persists during de/re-hydrogenation kinetics and cycling study of MgH2. The feasible mechanism for superior catalytic for TiH2@Gr on MgH2 has been put forward. © 2020 Hydrogen Energy Publications LLC
Mycosynthesis of bactericidal silver and polymorphic gold nanoparticles: Physicochemical variation effects and mechanism
(Future Medicine Ltd., 2018) Dheeraj Kumar Singh; Jitendra Kumar; Vijay Kumar Sharma; Satish Kumar Verma; Arti Singh; Puja Kumari; Ravindra Nath Kharwar
Aim: Extracellular synthesis of silver and gold nanoparticles using aqueous cell-free filtrate (CFF) of endophytic Chaetomium globosum and characterization of its bioactive proteins. Methods: Temperature and pH gradients were used to assess their effects on dimensions of NPs. NPs were tested in vivo for antibacterial activity. MALDI-TOF-MS/MS was used for characterization of CFF proteins. Results: Fungal CFF fabricated nanoparticles of various shape under varied physicochemical conditions. Silver nanoparticles showed significantly (p ≤ 0.5) enhanced antibacterial activity against Staphylococcus aureus and Klebsiella pneumoniae compared with AgNO3. Two prominent CFF proteins showed homology with benzoate 4-monooxygenase cytochrome P450 and ubiquinol-cytochrome c reductase. Conclusion: The study achieved controlled mycosynthesis of NPs and explains the hitherto poorly known mechanism of reduction, stabilization and antibacterial activity of nanoparticles. © 2018 Future Medicine Ltd.
Physically activated resorcinol-formaldehyde derived carbon aerogels for enhanced hydrogen storage
(Elsevier Ltd, 2025) Pargai Neema; Satish Kumar Verma; Mohammad Abu Shaz
Carbon aerogels have great potential as hydrogen storage materials owing to their exceptional specific surface area, low weight, and high porosity. These characteristics improve the ability to increase hydrogen adsorption capacity, making them promising candidates for hydrogen storage materials. Nevertheless, the implementation encounters obstacles such as limited storage capacity under ambient temperature and pressure. The present study reports the improved hydrogen storage capacity of carbon aerogels synthesized by Pekala's sol-gel method and optimized by physical activation. This study aims to optimize specific surface area and micropore volumes by physical activation to enhance hydrogen adsorption via the physisorption mechanism. The as-synthesized carbon aerogel has a specific surface area of 579.53 m2/g with a pore volume of 0.34 cm3/g whereas this surface area and pore volume have been tuned using its physical activation. The physically activated carbon aerogel shows a significantly higher specific surface area of 799.68 m2/g with a pore volume of 0.47 cm3/g as compared to the pristine carbon aerogel. This optimization in the specific surface area has enhanced the hydrogen storage capacity of carbon aerogel. The activated carbon aerogel exhibits a promising hydrogen storage capacity of 5.28 wt% at liquid nitrogen temperature under a hydrogen pressure of 22 atm whereas 3.39 wt% of hydrogen storage capacity has been seen in the unactivated carbon aerogel under the same conditions. In addition, activated carbon aerogel showed good hydrogen adsorption and desorption kinetics up to 30 cycles at room temperature (27 °C) under 22 atm hydrogen pressure. The reason behind enhanced hydrogen adsorption capacity in activated carbon aerogel has been put forward using various characterization techniques like XRD, TEM, SEM, and BET and discussed in the mechanism section. © 2024 Hydrogen Energy Publications LLC
Physically activated resorcinol-formaldehyde derived carbon aerogels for enhanced hydrogen storage
(Elsevier Ltd, 2024) Pargai Neema; Satish Kumar Verma; Mohammad Abu Shaz
Carbon aerogels have great potential as hydrogen storage materials owing to their exceptional specific surface area, low weight, and high porosity. These characteristics improve the ability to increase hydrogen adsorption capacity, making them promising candidates for hydrogen storage materials. Nevertheless, the implementation encounters obstacles such as limited storage capacity under ambient temperature and pressure. The present study reports the improved hydrogen storage capacity of carbon aerogels synthesized by Pekala's sol-gel method and optimized by physical activation. This study aims to optimize specific surface area and micropore volumes by physical activation to enhance hydrogen adsorption via the physisorption mechanism. The as-synthesized carbon aerogel has a specific surface area of 579.53 m2/g with a pore volume of 0.34 cm3/g whereas this surface area and pore volume have been tuned using its physical activation. The physically activated carbon aerogel shows a significantly higher specific surface area of 799.68 m2/g with a pore volume of 0.47 cm3/g as compared to the pristine carbon aerogel. This optimization in the specific surface area has enhanced the hydrogen storage capacity of carbon aerogel. The activated carbon aerogel exhibits a promising hydrogen storage capacity of 5.28 wt% at liquid nitrogen temperature under a hydrogen pressure of 22 atm whereas 3.39 wt% of hydrogen storage capacity has been seen in the unactivated carbon aerogel under the same conditions. In addition, activated carbon aerogel showed good hydrogen adsorption and desorption kinetics up to 30 cycles at room temperature (27 °C) under 22 atm hydrogen pressure. The reason behind enhanced hydrogen adsorption capacity in activated carbon aerogel has been put forward using various characterization techniques like XRD, TEM, SEM, and BET and discussed in the mechanism section. © 2024 Hydrogen Energy Publications LLC
Seed endophytes: Biology and biotechnology
(Springer International Publishing, 2019) Satish Kumar Verma; James Francis White
This book focuses on the importance and roles of seed microbiomes in sustainable agriculture by exploring the diversity of microbes vectored on and within seeds of both cultivated and non-cultivated plants. It provides essential insights into how seeds can be adapted to enhance microbiome vectoring, how damaged seed microbiomes can be assembled again and how seed microbiomes can be conserved. Plant seeds carry not only embryos and nutrients to fuel early seedling growth, but also microbes that modulate development, soil nutrient acquisition, and defense against pathogens and other stressors. Many of these microbes (bacteria and fungi) become endophytic, entering into the tissues of plants, and typically exist within plants without inducing negative effects. Although they have been reported in all plants examined to date, the extent to which plants rely on seed vectored microbiomes to enhance seedling competitiveness and survival is largely unappreciated. How microbes function to increase the fitness of seedlings is also little understood. The book is a unique and important resource for researchers and students in microbial ecology and biotechnology. Further, it appeals to applied academic and industrial agriculturists interested in increasing crop health and yield. © Springer Nature Switzerland AG 2019. All rights reserved.
Seed inhabiting bacterial endophytes of finger millet (Eleusine coracana L.) promote seedling growth and development, and protect from fungal disease
(Elsevier B.V., 2020) Kanchan Kumar; Gaurav Pal; Anand Verma; Satish Kumar Verma
The goal of this study was to evaluate the role of seed inhabiting bacterial endophytes on finger millet seedling development and protection from fungal infection. This study has shown that removal of endophytic bacteria from millet seeds compromised seedling health, however, re-inoculation of the same bacterial isolates restored its growth. A total of six endophytic bacteria were isolated from surface-sterilized seeds of finger millet and molecularly identified by 16S rDNA sequencing as Paenibacillus dendritiformis (EC1), Enterobacter hormaechei (EC2), Enterobacter cloacae (EC3), Bacillus safensis (EC4), Enterobacter hormaechei (EC5), and Enterobacter hormaechei (EC6). These isolated endophytes were tested for their plant growth-promoting activities. Enterobacter strains (EC2, EC3, EC5 and EC6) were found positive for IAA (Indole acetic acid) test and showed phosphate as well as potassium solubilization activities while siderophore production was shown by EC1 and EC4. Antifungal activity was also evaluated with isolate EC1 showing inhibition against all the tested phytopathogens. In seedling protection assay, bacterial endophytes significantly reduced the infection from Fusarium oxysporum. Re-inoculation experiment was carried out and it was found that bacterial strains EC1, EC4, and EC5 were most active in seedling development of finger millet, showing considerable improvement in root-shoot lengths, fresh weights and content of chlorophyll pigments. Endophytic bacterial colonization in the seedling roots was observed using fluorescent microscopy. This study reports the presence of endophytic bacteria inside seeds of finger millet having stimulatory effects on its growth and development. © 2020 SAAB
Seed inhabiting bacterial endophytes of maize promote seedling establishment and provide protection against fungal disease
(Elsevier GmbH, 2022) Gaurav Pal; Kanchan Kumar; Anand Verma; Satish Kumar Verma
Bacteria from different crops and plant varieties have been shown to possess enormous growth promotional attributes. The study aimed to investigate the role of the endophytic microbiome of seeds of corn in improving the growth of seedlings of two different varieties of maize crops (K-25 and baby corn). Furthermore, the study also assessed the role of these bacteria in the protection of seedlings from fungal pathogens. Total twenty-three endophytic bacterial strains were isolated from maize seeds and identified using 16S rDNA sequencing. Most of the isolates had the ability to synthesize auxin (70 %) and solubilize phosphate (74 %), while all the isolates showed nitrogen fixation ability. Some isolates also showed antagonistic activity against phytopathogenic fungi including Rhizoctonia solani and Fusarium sp. suggesting their biocontrol potential. The presence of different lipopeptide genes including bacillomycin D, fengycin, iturin A and surfactin was confirmed in some of the isolates. We observed that treating seeds with an antibiotic compromised the seedlings’ growth; however, re-inoculation with endophytic isolates (ZM1/Lysinibacillus sp. and ZM2/Paenibacillus dendritiformis) restored the growth of the seedlings in terms of improved root and shoot development in comparison to non-inoculated controls. The colonization of inoculated bacteria on the root surface was visualized using fluorescent microscopy. Seedling protection assay showed that treated seeds (with ZMW8/ Bacillus velezensis) were protected from fungal infestation (Fusarium verticillioides) even after 12 days of inoculation in comparison to the uninoculated control. The study concludes that indigenous seed-associated bacteria of maize play a major role during seed germination, seedling formation and protect them from phytopathogens. © 2021 Elsevier GmbH
Seed-vectored microbes: Their roles in improving seedling fitness and competitor plant suppression
(Springer International Publishing, 2019) James Francis White; Kathryn L. Kingsley; Susan Butterworth; Lara Brindisi; Judy W. Gatei; Matthew T. Elmore; Satish Kumar Verma; Xiang Yao; Kurt P. Kowalski
This chapter discusses the roles of seed-vectored microbes in modulating seedling development and increasing fitness of plants in terms of increased biotic and abiotic stress tolerance. Particular emphasis is placed on microbes that function in the rhizophagy cycle. These microbes have been shown to enter into root cells and stimulate root growth. In some cases microbe entry into root cells results in root growth repression. The term 'endobiome interference' has been applied to the phenomenon of plant growth repression due to intracellular microbes. The potential application of endobiome interference to produce bioherbicides that selectively enhance growth of target crops but inhibit competitor weeds is discussed. © Springer Nature Switzerland AG 2019.
STUDIES ON HYDROGEN STORAGE PERFORMANCE OF CATALYZED MgH2
(International Association for Hydrogen Energy, IAHE, 2022) Satish Kumar Verma; Mohammad Abu Shaz; Thakur Prasad Yadav
MgH2 is the widely investigated and one of the most prominent solid state hydrogen storage materials because of its high hydrogen storage capacity, low cost, and enormous elemental reserves in the earth crust and seawater. However, the high desorption temperature, sluggish kinetics and high thermal stability hinder its further onboard application. In present investigation, we have reported the enhanced kinetics and thermodynamics for MgH2 catalyzed through different prominent catalysts/additives like graphene (Gr), VS2, TiH2@Gr, Ti@Gr, TiO2@Gr, and high entropy alloy (HEA). Amongst these catalysts TiH2@Gr is most suitable catalyst for empowering the kinetics and thermodynamics of MgH2. The temperature programmed study reflects that MgH2-TiH2@Gr has lowest onset desorption temperature i.e., ~231 oC with a storage capacity ~6.55 wt% which is ~190 oC lower than the desorption temperature of pristine MgH2. The better catalytic behavior of MgH2-HEA on TiH2@Gr also persists during de/rehydrogenation kinetics of MgH2. Thus, MgH2 catalyzed by HEA absorbs ~5.9 wt% of hydrogen at 300 oC under 15 atm pressures in 1.5 min. A remarkable result coming out of the present investigation is concerning cyclability (reversibility) of MgH2-HEA, up to 25 cycles. © 2022 Proceedings of WHEC 2022 - 23rd World Hydrogen Energy Conference: Bridging Continents by H2. All rights reserved.