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Solar energy as prime energy source draws attention of world due to its availability and eco-friendliness. Low performance of solar air heater create curiosity for researchers to increase its performance. To enhance performance of solar air heater active and passive techniques used by researcher. Surface modification is one of the most prominent passive techniques to improve the performance. Present experimental and numerical investigation explore thermal characteristics of two-sided curvilinear rib roughened solar air heater. An indoor experiment was performed on two side curvilinear rib roughened absorber plate having constant heat flux of 1000 W/m2. Parallelly 2-dimensional numerical simulation was also performed to explore flow behavior and to complete investigation within optimum cost. ANSYS Fluent 2021.R was used for performing this simulation with K-ε RNG model with enhanced wall treatment. Velocity inlet and pressure outlet was selected as boundary condition. Main roughness and flow parameters were relative roughness height (e / D h = 0.21–0.042), relative roughness pitch (p / e = 7.14–35.71), and Reynolds number (Re = 3800–18,000). Maximum value of Nusselt number improvement ratio and friction factor improvement ratio was 3.17 and 3.26 at roughness and flow parameter of (e / D h = 0.042, p / e = 15, Re = 15,000) and (e / D h = 0.042, p / e = 7.14, Re = 3800) respectively. Thermohydraulic performance parameter achieved its maximum value of 2.77 at e / D h = 0.042, p / e = 17.85, and Re = 18,000. [ABSTRACT FROM AUTHOR]

The main objective of this work is to synthesize multifunctional nanodendritic structural molecules that can effectively encapsulate hydrophilic as well as hydrophobic therapeutic agents. Four different types of fourth-generation lysine-citric acid based dendrimer have been synthesized in this work: PE-MC-Lys-CA-PEG, TMP-MC-Lys-CA-PEG, PE-MS-Lys-CA-PEG, and TMP-MS-Lys-CA-PEG. The antibacterial drug cefotaxime (CFTX) was further conjugated to these dendrimers. The dendrimer and drug-dendrimer conjugate structures were characterized with the help of FTIR,1H-NMR, and 13C-NMR spectroscopy. Zeta sizer, AFM, and HR-TEM techniques were used to investigate the particle size, surface topography, and structural characteristics of drug-dendrimer conjugates. In vitro drug release was then investigated using dialysis method. Various kinetic drug release models were examined to evaluate the type of kinetic drug release mechanism of the formulations. Cytotoxicity study revealed that the dendrimers encapsulated with CFTX exhibited 2-3% toxicity against healthy epithelial cells, indicating their safe use. Plain dendrimers show 10-15% hemolytic toxicity against red blood cells (RBC), and the toxicity was reduced to 2-3% when CFTX was conjugated to the same dendrimers. The 3rd and 4th generation synthesized drug-dendrimer conjugates exhibit a significantly effective zone of inhibition (ZOI) against both Gram-positive and Gram-negative bacteria. For Gram-positive bacteria, the lower concentration of 0.1 mg/mL showed more than 98% inhibition of drug-dendrimer conjugate samples against B. subtilis and more than 50% inhibition against S. aureus using 0.2 mg/mL, respectively. Moreover, samples with concentrations of 0.5 and 1.0 mg/mL exhibited more than 50% inhibition against S. typhimurium and E. coli, respectively. [ABSTRACT FROM AUTHOR]

An outdoor experimental investigation was conducted to explore the thermohydraulic characteristic (Nusselt no. and friction factor) of artificial roughened solar air heater (ARSAH) having frustrum shaped roughened element on absorber plate. Data were recorded and further processed to generate Nusselt number and friction factor correlation to predict the effect of flow and roughness parameter on performance of ARSAH. The investigation was conducted by varying Reynolds number in range of 2500–12,500. Dimensionless parameter for Frustrum shaped roughness was relative frustum height (e/Dh) from 0.013 to 0.054, relative frustum pitch (p/e) from 8 to 14, Relative frustum height to base diameter (e/d1) from 0.37 to 0.75, relative frustum diametral ratio (d1/d2) from 1 to 3. Maximum performance for ARSAH was obtained corresponding to the optimum value of flow and geometric parameter. The geometric orientation of the proposed roughness geometry produced tremendous rise in Nu with an acceptable rise in friction (f). Maximum enhancement in Nu for varying p/e, e/Dh, e/d1, and d1/d2 was, 4.58, 5.21, 6.62 and 6.09 times and that of friction was 5.59, 4.69, 4.92 and 4.66 times respectively over conventional SAH. Maximum Thermohydraulic performance was 3.7, 3.6, 3.9 and 3.8 at p/e = 12, e/Dh = 0.054, e/d1 = 0.75 and d1/d2 = 3. [ABSTRACT FROM AUTHOR]

Canal irrigation system, besides providing irrigation, generate many ecosystem services for command areas, viz. lesser groundwater extraction and carbon emissions, energy savings, groundwater recharge, recreational services for inhabitants, etc. However, existing studies primarily emphasize irrigation services provided by canals while overlooking other ecosystem services. Therefore, this study monetizes key ecosystem services rendered by the Eastern Yamuna Canal (EYC) and collates government expenditures incurred. The result shows that the ecosystem services delivered by EYC are worth Rs 1122.86 million, nearly 48.27% more than working expenses. Further, the result highlights that anchoring only on revenue generated to exchequer with water rates, to compare the performance of any canal will not be sufficient. The present study suggests that if the government facilitates the timely availability of canal water to the farms and collects water charges equal to working expenses from the water users, it could be a much better trade-off for the stakeholders. [ABSTRACT FROM AUTHOR]

The study analysed the investment and returns of installing solar-powered pumps, besides their economic feasibility and efficiency in arid and sub-humid regions of Rajasthan based on primary data collected for the year 2018-19. The feasibility analysis while accounting for different climatic regions of Rajasthan is imperative to examine since it influences the depth of water table and required power to extract groundwater which would, affect economic feasibility of pumps. Only subsidised investment in solarpowered tubewells was found to be economically feasible in both regions. The efficiencies of solar-irrigated farms and savings in cost after installing solar-powered pumps were found to be higher for sub-humid region, which may be attributed to better utilisation of solar pumps, cultivation of high-value vegetables and adoption of improved technologies. The major constraint faced by farmers in adoption of solar-powered pumps in arid region was found to be their non-functioning in higher water table situations, while in sub-humid region, it was a high initial investment. Hence, there is need to have custom-made policies according to climatic regions of the country and to increase awareness regarding benefits of adoption of advanced technologies and high-value crops which can complement the benefits of adoption of solar-powered pumps. [ABSTRACT FROM AUTHOR]

The study was undertaken to assess the effect of in-situ paddy straw management by the adoption of Happy Seeder and PUSA decomposer on the profitability in wheat cultivation and constraints to the adoption of these technologies using primary data collected from randomly selected 121 farmers in the Karnal district of Haryana in the year 2022. The results showed that the adoption of these technologies has reduced the cost and increased the profitability in wheat cultivation. However, the adoption of these technologies especially among small farmers remains limited. Financial constraints to the adoption of Happy Seeder and the longer duration for the decomposition of straw by PUSA decomposer were reported to be major hindrances in their adoption. Educating the farmers regarding the consequences of stubble burning and the potential benefits of adopting these technologies and addressing financial constraints and improving the efficacy of PUSA decomposer may be the potential options for sustainable management of paddy straw. [ABSTRACT FROM AUTHOR]

Almost every aspect of library services has been significantly and widely impacted by the introduction of information technology. A new generation of libraries with an emphasis on electronic resources has emerged as a result of the quick changes in the library environment. The growing prevalence of Electronic Resources has raised concerns among librarians and staff regarding these resources, their techniques, accessibility, assessment, organisation, and selection. This study has uncovered the current state of Electronic Resources in a few academic libraries located in Uttarakhand. The study also demonstrates the benefits of using Electronic Resources, the challenges users have when trying to access them, and how academic library users view the influence of Electronic Resources. Electronic resources have completely changed library services and operations today. Today, most people can sit down at a computer and conduct online information searches. Ten years ago, most searches took place in libraries and information centres and were mostly tied to scientific and technical bibliographic databases. However, today, these searches are much more popular in the office and at home. [ABSTRACT FROM AUTHOR]

Pigments are an essential part of life on earth, ranging from microbes to plants and humans. The physiological and environmental cues induce microbes to produce a broad spectrum of pigments, giving them adaptation and survival advantages. Microbial pigments are of great interest due to their natural origin, diverse biological activities, and wide applications in the foods, Pharmaceuticals, cosmetics, and textile industries. Despite noticeable research on pigment-producing microbes, commercial successes are scarce, primarily from higher, remote, and inaccessible Himalayan niches. Therefore, substantial bioprospection integrated with advanced biotechnological strategies is required to commercialize microbial pigments successfully. The current review elaborates on pigment-producing microbes from a Himalayan perspective, offering tremendous opportunities for industrial applications. Additionally, it illustrates the ecological significance of microbial pigments and emphasizes the current status and prospects of microbial pigment production above the test tube scale. [ABSTRACT FROM AUTHOR]