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In the present investigation, diverse functionalized states of multi-walled carbon nanotubes (MWCNT) were employed in fabricating glass/epoxy composites, with the MWCNT consistently incorporated at a 0.5 wt.% concentration. These functionalization states included pristine, hydroxyl, amine, and carboxylic conditions, systematically compared against neat glass/epoxy composites. The findings elucidated that all three functionalizations positively influenced the enhancement of interlaminar shear strength, mode-I interlaminar fracture toughness, and mode-II interlaminar fracture toughness properties. Notably, the amine-functionalized MWCNT exhibited superior performance relative to other formulations. The composite reinforced with amine MWCNT demonstrated significant improvements in ILSS, mode-I ILFT, and mode-II ILFT by 41.82%, 37.75%, and 40.93%, respectively. These enhancements are attributed to factors such as the presence of a more functional group, the quantity of individual MWCNT, and the introduction of additional damage mechanisms, including MWCNT pullout and bridging. Highlights: Improvement in ILSS of glass/epoxy composite by functionalized MWCNT by 20.11-41.82% range. Improvement in mode-I ILFT of glass/epoxy composite by functionalized MWCNT by 5.54-30.81%. Improvement in mode-II ILFT of glass/epoxy composite by functionalized MWCNT by 8.46-40.93%. Microscopic characterization using field-emission scanning electron microscopy revealed existence of MWCNT pullout and bridging. [ABSTRACT FROM AUTHOR]

Solvent extraction using a microfluidic platform is one of the process intensification tools. It may involve different two-phase flow regimes that have different physical and mass transfer characteristics. Therefore, this study focuses on the selection of a better flow regime, flow conditions and cascade configuration (cross or counter-current) using mathematical modeling for a typical high-throughput application (1000 L/day). The mathematical model is based on a plug flow model. The liquid–liquid system considered is a water–acetone–toluene system. The different flow regimes such as slug flow (SF), slug-droplet flow (SDF) and core-annular flow (CAF) in different cascade configurations are compared on the basis of parameters like specific extraction rate (SER), solvent extraction process effectiveness (SEPE) and modified merit index (MMI). Among the different flow regimes and cases studied, CAF is found to offer lesser parallel paths, total extraction length, total pressure drop and residence time. The best case of CAF has higher SER (3.6 times), SEPE (3.6 times) and MMI (21.8 times) than the best case of SF in both cascades. SDF shows the results between SF and CAF. For a specific flow regime, higher values of parameters are obtained at higher flow rates. Counter-current cascade is found to be better than cross-current cascade. [ABSTRACT FROM AUTHOR]

In this work, a capillary microfluidic platform based on microbore tubes is demonstrated to continuously synthesize chromium hydroxide microspheres with a narrow particle size distribution using sol-gel process. Chromium hydroxide microspheres are later calcined to obtain chromium oxide microspheres. An in-situ mixing technique is utilized to mix the chromium precursor with the gelling agent. The effects of different design (microfluidic junction configuration, size of the microbore tube) and operating variables (continuous to dispersed phase flow rate ratio, flow velocity, residence time) on the average diameter and polydispersity index of microspheres are studied systematically. Microspheres of an average size of 574 μm with polydispersity index of 6.6% could be prepared using a double T-junction at an organic to aqueous (O/A) flow rate ratio of 60 in an 800 µm diameter microbore tube. The detailed analysis of the flow conditions reveals that the regime of drop (of aqueous phase) formation varies between transition and dripping. Finally, a correlation is proposed to predict average diameter of the microspheres based on values of capillary number (Ca) and organic to aqueous (O/A) flow rate ratio. [ABSTRACT FROM AUTHOR]

The purpose of the present paper is to study a sequence of linear and positive operators which was introduced by A. Lupas. First, we obtain estimate of moments of the operators and then prove a basic convergence theorem for simultaneous approximation. Further, we find error in approximation in terms of modulus of continuity of function. Finally, we establish a Voronovskaja asymptotic formula for linear combination of the above operators. [ABSTRACT FROM AUTHOR]

Rice (Oryza sativa) is a staple food of more than half of the population of the world and provides food security and livelihoods for millions of population. Direct seeding of rice (DSR) refers to the process of direct sowing the seeds in the field rather than by transplanting seedlings from the nursery. Direct seeded rice is an age old practice and before the introduction of green revolution in India. Rainfed rice was often broadcasted into moist soil and crops were highly prone to weed competition resulted into low yield. Rice ecosystems and establishment methods determined the weed spectrum and degree of infestation in rice field (DSR). Weeds are considered as a major biological constraint in direct seeded rice. In direct seeded rice, weed management depend on weed flora, critical period of weed control, availability of water and method to be adopted. Integrated weed management (IWM) is essential to achieve the long term, sustainable and economic management of weeds in direct seeded rice. The literature regarding the direct seeded rice, critical period of crop weed competition, different types of weed flora and different methods for the effective and sustainable management of weeds in direct seeded rice are reviewed in this paper. [ABSTRACT FROM AUTHOR]

Uttar Pradesh, with a population of 237 million, is the largest agrarian state in India, located in the Indo‐Gangetic plains. Rice cultivation is widespread across all districts of Uttar Pradesh, which have varying climate regimes, irrigation infrastructures, crop management practices, and farm sizes. The state is characterized by different agroecological zones (AEZs) with semi‐arid to sub‐humid climates with significant variability in monsoon rainfall. In this study, the impact of climate change on Kharif‐season rice is estimated using crop‐climate scenarios in Uttar Pradesh. A process‐based Crop Simulation Model, Crop Estimation through Resource and Environment Synthesis‐Rice, was simulated with bias‐corrected and downscaled climate data for historical (1995–2014) and three future periods (the 2030s, 2050s, and 2090s) for two mitigation pathways (SSP2‐4.5 and SSP5‐8.5) from the Coupled Model Intercomparison Project 6. Phenology, irrigation amount, crop evapotranspiration, yield, and water use efficiency were evaluated and assessed for all AEZs. Based on the ensemble of 16 climate models, rainfed rice yield increased in the AEZs of western Uttar Pradesh due to increased rainfall, while in eastern Uttar Pradesh yield decreased, under both shared socioeconomic pathways (SSPs). Irrigated rice yield decreased in all AEZs under both SSPs due to an increase in temperature and a decrease in the length of the growing period, with reductions of up to 20% by the 2090s. Irrigation requirements decreased from the 2030s to the 2090s due to increased rainfall and decreased crop evapotranspiration. Despite the projected increase in rainfed yield, the overall rice yield is expected to decrease in the future under both SSPs. Plain Language Summary: Uttar Pradesh is the most populated state in India, with most of the population working in the agriculture sector and having a low income. The state's vulnerability to climate change is high due to inadequate infrastructure and heavy dependence on agriculture. Rice is a crucial crop for the state, but this study shows that climate change will decrease rice yields in the future, especially for irrigated rice, due to higher temperatures and shorter growing seasons. While rainfed rice yields may increase in some regions due to increased rainfall, rice production is expected to decline overall. Key Points: Rice yield (combining irrigated and rainfed) in Uttar Pradesh, India, is projected to decrease in the future for SSP2‐4.5 and SSP5‐8.5With a projected increase in rainfall, rainfed rice yield increases in rainfall deficit zones, and irrigation decreases under both shared socioeconomic pathwaysPlanting in the early season could reduce the amount of yield loss for irrigated rice [ABSTRACT FROM AUTHOR]

A microfluidic platform to synthesize monodispersed and spherical hydrogel beads (microspheres) of poly(acrylamide-co-acrylic acid) (p(AM-co-AA)) is reported. An aqueous phase consisting of monomer, cross-linker, functional moiety and initiator, all dissolved in water, is dispersed as uniform drops of desired size into a carrier phase (dodecane) at an opposed T-junction. The chemical and physical properties of the microspheres are systematically studied. Effects of operating parameters like velocity and O/A (oil to aqueous phase flow ratio) ratio on the average size, polydispersity and shape of microspheres are investigated. Microspheres within a size range of 960 to 502 microns can be synthesized. A comparison of two different mixing techniques namely in-situ and ex-situ mixing is also presented. A two dimensional computational fluid dynamic (2 D CFD) model is also developed to quantify and validate drop formation phenomena at the T junction at extreme O/A ratios. Detailed numerical insights on the velocity and pressure field at the junction have been provided. [ABSTRACT FROM AUTHOR]

Accurate and timely information on evapotranspiration (ET0) is essential for multiple agricultural applications, including irrigation scheduling, studying crop-specific water loss at different growth stages, predicting crop yields, and forecasting drought conditions. This study aims to examine the spatiotemporal patterns of ET0 and facilitate the monitoring of crop water demand, optimize irrigation water usage, and enhance agricultural advisory services. This paper estimates regional-level daily ET0 gridded data with a spatial resolution of 12.5 km by integrating observed weather data, IMD GFS-T1534 reanalysis data, and INSAT-3D satellite-based insolation product using the standard FAO56 Penman–Monteith empirical equation. The estimated monthly mean of ET0 across India ranged from 10 to 400 mm. ET0 exhibited an increasing trend from January to May, reaching its maximum values in May. In June, ET0 significantly decreased as the monsoon arrived, coinciding with the movement of rainfall patterns. The month of December exhibited the lowest ET0 values. The estimated daily gridded ET0 was compared with station-based ET0, resulting in daily correlation coefficient R2 and daily maximum absolute percentage errors ranging from 0.34 to 0.90 and 10% to 27% respectively. However, these errors decreased to a large extent when considering multiday accumulated values. A comparison was conducted between the GLDAS model ET0 and the station-estimated values, revealing an overestimation of ET0 by the GLDAS model. Additionally, significant variations were observed among the meteorological subdivisions. This highlights the necessity for proper calibration of the GLDAS model ET0 or its effective agricultural application. [ABSTRACT FROM AUTHOR]

A novel air pulsed column plate internal featuring plates having concentric circular slots of fixed width (3 mm) is conceptualized, tested, and compared against standard sieve plate internal for counter-current two-phase flow. This new plate design (slotted plates) offers significant intensification in terms of specific interfacial area by as much as ~ 50% vis-à-vis standard sieve plates. The studies are carried out in a 3 inch diameter air pulsed column with tap water as the continuous phase and 30% (v/v) tributyl phosphate in dodecane as the dispersed phase. A high-speed imaging system is used to quantify the state of dispersion and obtain drop size distribution along with Sauter mean drop diameter. The effects of pulsing velocity, dispersed phase velocity and continuous phase velocity on dispersed phase holdup, drop size and consequentially specific interfacial area have been systematically studied for both internals. In all cases, slotted plates are characterized by generation of smaller drops and a higher holdup leading to significant improvement in specific interfacial area. Previously reported correlations for estimating dispersed phase holdup and Sauter mean diameter in pulsed sieve plate columns are found to be inadequate for slotted plate internals. Therefore, new correlations for prediction of holdup and drop diameter have been proposed for the new plate design. [ABSTRACT FROM AUTHOR]

This paper presents a study conducted in the Sultanpur district of Uttar Pradesh, focusing on the marketing of bitter gourd in the selected area. The research employed a multistage stratified purposive cum random sampling technique to select the district, block, villages, and respondents. From the population, 100 growers were randomly chosen, comprising 66 marginal, 23 small, and 11 medium farmers during the period of 2021-2022, using the proportionate allocation technique. Primary data were collected through face-toface interviews using a survey schedule. Three distinct marketing channels for bitter gourd were identified: Channel-I (producer to consumer), Channel-II (producer to retailer to consumer) and Channel-III (producer to wholesaler to retailer to consumer). The study revealed that Channel-I exhibited the highest marketing efficiency (29.15), followed by Channel-II (5.47) and Channel-III showed the lowest efficiency (2.96). Notably, different groups of farms predominantly sold bitter gourd through Channel-III. The research also shed light on the challenges faced by bitter gourd growers, including issues related to perishability, price fluctuations, and inadequate storage facilities. The paper emphasizes the significance of policymakers and stakeholders addressing these challenges and developing effective strategies and interventions to support the bitter gourd farming community. [ABSTRACT FROM AUTHOR]

Radioactive scandium-46 microspheres have applications in mapping flow in a chemical reactor through a technique known as radioactive particle tracking (RPT). In the present study a novel microfluidic method has been developed for synthesis of controlled size scandium oxide microspheres. An inline/in-situ mixing of the scandium precursor and gelling agents was implemented which makes the microfluidic platform amenable for truly continuous operation. Microspheres of size varying from 937 to 666 μm were produced by varying O/A ratio from 10 to 30. Perfectly spherical and monodispersed (PDI <10 %) microspheres were obtained at O/A 15 and beyond. The morphology, elemental composition, and structure of the microspheres were analysed by SEM, EDS and XRD, respectively. Subsequently the microspheres were irradiated with thermal neutrons in a nuclear reactor to obtain radioactive Sc-46 oxide microspheres. The activity produced on each Sc-46 microspheres with different sizes was in the range 19.5-34.0 MBq., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Ltd. All rights reserved.)