| 1. |
|
|
| 2. |
- Ahuja, Vishal, et al.
(författare)
-
Microbial alchemy : upcycling of brewery spent grains into high-value products through fermentation
- 2023
-
Ingår i: Critical reviews in biotechnology. - : Taylor & Francis. - 0738-8551 .- 1549-7801.
-
Forskningsöversikt (refereegranskat)abstract
- Spent grains are one of the lignocellulosic biomasses available in abundance, discarded by breweries as waste. The brewing process generates around 25–30% of waste in different forms and spent grains alone account for 80–85% of that waste, resulting in a significant global waste volume. Despite containing essential nutrients, i.e., carbohydrates, fibers, proteins, fatty acids, lipids, minerals, and vitamins, efficient and economically viable valorization of these grains is lacking. Microbial fermentation enables the valorization of spent grain biomass into numerous commercially valuable products used in energy, food, healthcare, and biomaterials. However, the process still needs more investigation to overcome challenges, such as transportation, cost-effective pretreatment, and fermentation strategy. to lower the product cost and to achieve market feasibility and customer affordability. This review summarizes the potential of spent grains valorization via microbial fermentation and associated challenges.
|
|
| 3. |
- Bhatia, Shashi Kant, et al.
(författare)
-
Introduction to microbial exopolysaccharides
- 2024
-
Ingår i: Microbial exopolysaccharides. - : CRC Press. - 9781032379418 - 9781032379425 - 9781003342687 ; , s. 1-5
-
Bokkapitel (refereegranskat)
|
|
| 4. |
- Bui, Thai Q., et al.
(författare)
-
Switchable aqueous pentaethylenehexamine for CO2 capture and beyond
- 2018
-
Ingår i: 23rd International Congress of Chemical and Process Engineering, CHISA 2018 and 21st Conference on Process Integration, Modelling and Optimisation for Energy Saving and Pollution Reduction, PRES 2018. - : Czech Society of Chemical Engineering. - 9781510881198 ; , s. 143-144
-
Konferensbidrag (refereegranskat)
|
|
| 5. |
- Bui, Thai Q., et al.
(författare)
-
Switchable Aqueous Pentaethylenehexamine System for CO2 Capture : an Alternative Technology with Industrial Potential
- 2018
-
Ingår i: ACS Sustainable Chemistry and Engineering. - : American Chemical Society (ACS). - 2168-0485. ; 6:8, s. 10395-10407
-
Tidskriftsartikel (refereegranskat)abstract
- Herein we report the application of polyamine pentaethylenehexamine (PEHA, 3,6,9,12-tetraazatetradecane-1,14-diamine) in CO2 absorption with both neat PEHA and aqueous solutions thereof. The absorption of molecular CO2 in pure PEHA and in PEHA-water systems resulted in the formation of two chemical species, namely, PEHA carbamate and bicarbonate. It was observed that, upon formation of these species, both the CO2 absorption capacity and CO2 absorption rate were controlled by the amount of water in the system. During the CO2 absorption, the neat PEHA and 92 wt % PEHA were capable of forming carbamate species only while other aqueous analogues with higher dilution allowed for the formation of both carbamate and bicarbonate species upon exceeding 8 wt % water in the mixture. The CO2 uptake steadily increased with an increase in the water concentration in the solvent mixture and reached the maximum value of 0.25 g of CO2/(g of solvent) in the case of 56 wt % PEHA in water. However, in the case of more dilute systems (i.e., <56 wt % PEHA in water), the trend reversed and the CO2 loading decreased linearly to 0.05 g of CO2/(g of solvent) for 11 wt % PEHA in water. Meanwhile, it usually took shorter time to achieve the full CO2 absorption capacity (equilibrium) with increasing water content in all cases. The C-13 NMR analysis was used to quantify the relative amount of PEHA carbamate and bicarbonate, respectively, in reaction mixtures. The Kamle-Taft parameters (alpha, beta, and pi*) of aqueous solutions for different concentrations of PEHA were also studied taking advantage of various solvatochromic dyes and correlated with the CO2 absorption capacity. The thermally induced switchable nature of CO2-saturated neat and aqueous PEHA solutions for transformation of ionic PEHA carbamate and bicarbonate moieties to molecular PEHA is also represented. A comparison between aqueous PEHA and aqueous monoethanolamine (industrial solvent) for CO2 capture is reported. Hence, most importantly, a switchable PEHA system is demonstrated for reversible CO2 absorption processes.
|
|
| 6. |
- Gurav, Ranjit, et al.
(författare)
-
Production, characterization, and application of biochar for remediation of dyes from textile industry wastewater
- 2023
-
Ingår i: Current Developments in Bioengineering and Biotechnology. - : Elsevier BV. ; , s. 231-251
-
Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- Dyes are coloring agents widely used in the textile and leather industries. Synthetic dyes are the major contributor to global wastewater exhibiting toxic effects on humans, aquatic organisms, and the environment. The conventional decolorization treatments are less effective due to high dye concentration in wastewater, complex chemical structure, and poor biodegradability. Several strategies like physical, chemical, and biological were reported earlier for dye decolorization. However, the adsorption technique has been extensively considered from economic and ecological standpoints. Biochar, a carbonaceous material generated by pyrolyzing waste biomass has been discussed here to tackle the dye-containing wastewater. As an adsorbent, biochar has gained considerable attention owing to its underlying advantages like larger surface area, high porosity, low production cost, varied surface functional groups, easy surface modifications, exceptional hydrophobicity, and aromaticity. In this chapter, we have discussed approaches for the production, and characterization of the biochar. Furthermore, we have also considered the effect of different physicochemical properties, sorption kinetics, isotherm models, and other key factors affecting the sorption mechanism. In this perspective, an effort has been made in this chapter to explore the probability and practicability of biochar as a sorbent for removal of the textile dyes.
|
|
| 7. |
- Ji, Linan, et al.
(författare)
-
An overview of the progress of new working pairs in absorption heat pumps
- 2023
-
Ingår i: Energy Reports. - : Elsevier Ltd. - 2352-4847. ; 9, s. 703-729
-
Forskningsöversikt (refereegranskat)abstract
- Absorption heat pumps have emerged as a potential tool to address the energy crisis because of their ability to utilize low-grade heat. The performance of an absorption heat pump largely depends on the efficiency of the working pair to operate at the source temperature. The commercialized working pairs H2O/LiBr and NH3/H2O linger with operational and economic issues. Several binary/ternary combinations were tested among water, ammonia, salt, alcohols, hydrocarbons, and ionic liquids (ILs) in quest of the potential working pairs. The last decade has witnessed a stupendous surge in IL-based working pairs because of their several advantageous properties over the traditional solvents. The present review encompasses the research progress on various working pairs, in particular, their properties, modeling and correlation results, and coefficient of performance (COP) values.
|
|
| 8. |
- Kant Bhatia, Shashi, et al.
(författare)
-
An overview on microalgal-bacterial granular consortia for resource recovery and wastewater treatment
- 2022
-
Ingår i: Bioresource Technology. - : Elsevier. - 0960-8524 .- 1873-2976. ; 351
-
Forskningsöversikt (refereegranskat)abstract
- Excessive generation of wastewater is a matter of concern around the globe. Wastewater treatment utilizing a microalgae-mediated process is considered an eco-friendly and sustainable method of wastewater treatment. However, low biomass productivity, costly harvesting process, and energy extensive cultivation process are the major bottleneck. The use of the microalgal-bacteria granular consortia (MBGC) process is economic and requires less energy. For efficient utilization of MBGC, knowledge of its structure, composition and interaction are important. Various microscopic, molecular and metabolomics techniques play a significant role in understating consortia structure and interaction between partners. Microalgal-bacteria granular consortia structure is affected by various cultivation parameters like pH, temperature, light intensity, salinity, and the presence of other pollutants in wastewater. In this article, a critical evaluation of recent literature was carried out to develop an understanding related to interaction behavior that can help to engineer consortia having efficient nutrient removal capacity with reduced energy consumption.
|
|
| 9. |
- Kant, Shashi, et al.
(författare)
-
Efficient Optimization for Large-Scale MIMO-OFDM Spectral Precoding
- 2021
-
Ingår i: IEEE Transactions on Wireless Communications. - : Institute of Electrical and Electronics Engineers (IEEE). - 1536-1276 .- 1558-2248. ; 20:9, s. 5496-5513
-
Tidskriftsartikel (refereegranskat)abstract
- Although spectral precoding is a propitious technique to suppress out-of-band emissions, it has a detrimental impact on the system-wide throughput performance, notably, in high data-rate multiple-input multiple-output (MIMO) systems with orthogonal frequency division multiplexing (OFDM), because of (spatially-coloured) transmit error vector magnitude (TxEVM) emanating from spectral precoding. The first contribution of this paper is to propose two mask-compliant spectral precoding schemes, which mitigate the resulting TxEVM seen at the receiver by capitalizing on the immanent degrees-of-freedom in (massive) MIMO systems and consequently improve the system-wide throughput. Our second contribution is an introduction to a new and simple three-operator consensus alternating direction method of multipliers (ADMM) algorithm, referred to as TOP-ADMM, which decomposes a large-scale problem into easy-to-solve subproblems. We employ the proposed TOP-ADMM-based algorithm to solve the spectral precoding problems, which offer computational efficiency. Our third contribution presents substantial numerical results by using an NR release 15 compliant simulator. In case of perfect channel knowledge at the transmitter, the proposed methods render similar block error rate and throughput performance as without spectral precoding yet meeting out-of-band emission (OOBE) requirements at the transmitter. Further, no loss on the OOBE performance with a graceful degradation on the throughput is observed under channel uncertainty.
|
|
| 10. |
- Kant, Shashi, et al.
(författare)
-
EVM-Constrained and Mask-Compliant MIMO-OFDM Spectral Precoding
- 2021
-
Ingår i: IEEE Transactions on Wireless Communications. - : IEEE. - 1536-1276 .- 1558-2248. ; 20:1, s. 590-606
-
Tidskriftsartikel (refereegranskat)abstract
- Spectral precoding is a promising technique to suppress out-of-band emissions and comply with leakage constraints over adjacent frequency channels and with mask requirements on the unwanted emissions. However, spectral precoding may distort the original data vector, which is formally expressed as the error vector magnitude (EVM) between the precoded and original data vectors. Notably, EVM has a deleterious impact on the performance of multiple-input multiple-output orthogonal frequency division multiplexing-based systems. In this paper we propose a novel spectral precoding approach which constrains the EVM while complying with the mask requirements. We first formulate and solve the EVM-unconstrained mask-compliant spectral precoding problem, which serves as a springboard to the design of two EVM-constrained spectral precoding schemes. The first scheme takes into account a wideband EVM-constraint which limits the average in-band distortion. The second scheme takes into account frequency-selective EVM-constraints, and consequently, limits the signal distortion at the subcarrier level. Numerical examples illustrate that both proposed schemes outperform previously developed schemes in terms of important performance indicators such as block error rate and system-wide throughput while complying with spectral mask and EVM constraints.
|
|
