Daily Archives: September 16, 2026

Authors: Ephraim Anthony Jacob, Jackson.G. Akpa, Fidelis. O. Wopara

Abstract: The work entails research on recovery of crude oil losses to effluent water disposal system in the production platform using sand as the filtration media. In this dissertation a glass column filled with sand is used as a low-cost filtration media for the removal of crude oil from synthetic oil produced water (SOPW) and real produce water PW from oil and gas wells. The objective of this work is to examine the filtration efficiency of sand grains tilled in a glass column as sand filter in recovering crude oil from produced water. This work investigates the influence of process parameters such as physical characteristics of sand, column height, types of effluent (oilfield produced water and synthetic oil produced water), and oil concentration on oil removal efficiency. The sand fractions used for this work was selected using a set of Tyler sieves. After the different grain sizes were selected, the sand was washed several times to remove impurities. The sand samples were oven dried at 1000C for 24h. The gravel was washed and also dried at 1000C, for l2h. Oil was removed from laboratory-produced water in a batch process at standard atmospheric conditions. The effect of contact time, physical characteristics of sand, column height, pH as well as temperature on the removal efficiency of oil was investigated. The optimum parameters for oil removal were: pH 9.5, contact time 40.0 minutes and temperature 55.00C. The results showed that the oil concentration decreased significantly after the filtration process. The oil removal efficiency was influenced by the sand particle size and bed height, reaching 90% using a 30 cm high sand bed composed by mixed grain sizes.

DOI: https://doi.org/10.5281/zenodo.22805792

Published by: vikaspatanker

Authors: Associate Professor N.Chandanaa, Assistant Professor Vijaya Ushasreeb

Abstract: Nanocomposite cotton fabrics (NCCFs) embedded with in situ generated silver nanoparticles (AgNPs) were successfully prepared using an eco‑friendly green synthesis approach. Lemon leaf extract was employed as a natural reducing and stabilizing agent to functionalize cotton fabrics and facilitate the formation of AgNPs within the cotton matrix. The incorporation of phytochemicals from the extract enabled effective reduction of silver ions and strong adhesion of nanoparticles onto the cellulose fibers. The synthesized NCCFs were characterized using X‑ray diffraction (XRD), scanning electron microscopy (SEM) coupled with energy dispersive X‑ray analysis (EDX), Fourier transform infrared spectroscopy (FTIR), and thermogravimetric analysis (TGA). XRD results confirmed the presence of crystalline silver nanoparticles along with cellulose structure, while SEM analysis revealed uniformly distributed spherical AgNPs with sizes increasing with higher precursor concentration. EDX analysis verified the elemental composition of silver within the fabric. FTIR studies indicated that the fundamental structure of cotton remained intact, with interactions between AgNPs and functional groups occurring primarily through electrostatic forces. TGA results showed a slight reduction in thermal stability of NCCFs compared to the untreated cotton matrix. The antibacterial activity of NCCFs was evaluated against Gram-positive (Staphylococcus aureus, Bacillus subtilis) and Gram-negative (Escherichia coli, Pseudomonas aeruginosa) bacteria using the agar diffusion method. The prepared nanocomposites exhibited significant antibacterial performance, with inhibition zones ranging from 11 to 25 mm, whereas untreated cotton fabrics showed no antibacterial activity.

DOI: https://doi.org/10.5281/zenodo.22791801

Published by: vikaspatanker

Authors: Pradip G. Gavade, Vivek V. Patil

Abstract: This study presents an experimental investigation of vibration localization in flexible rotating shafts under simply supported boundary conditions. Three shaft configurations were considered: circular stainless steel 304, non-circular stainless steel 304, and circular brass. The experimental program used an accelerometer, impact hammer, FFT analyzer, DC motor, coupling, and bearing supports to determine the natural frequencies and steady-state vibration responses. The non-circular shaft introduced a small difference between the two lateral moments of inertia; therefore, it represents a mistuned configuration. The experimental natural frequencies of 85.23 Hz, 89.84 Hz, and 75.78 Hz were obtained for circular stainless steel, non-circular stainless steel, and circular brass were 85.23, 89.84, and 75.78 Hz, respectively. The normalized forced responses increased with rotational speed, demonstrating the sensitivity of the vibration response to rotational speed and structural asymmetry. At 1000, 2000, and 3000 rpm, normalized responses of 0.03384, 0.18, and 0.5259 were obtained for circular stainless steel; 0.03565, 0.159, and 0.448 for non-circular stainless steel; and 0.0508, 0.2398, and 0.7706 for circular brass.

DOI: http://doi.org/10.5281/zenodo.22791683

Published by: vikaspatanker

Authors: Monish Kanungo, Seemant Kaushal

Abstract: Classical software memory leaks are allocations that outlive their intended lifetime. Tool-using large language model (LLM) agents exhibit an analogous failure that current “forgetting” mechanisms do not measure. A user or policy issues a forget request for a memory m*; the underlying store correctly drops the record, and content probes no longer reproduce the fact; yet the agent’s tool-selection behavior on the next turn continues to favor the same tool that m* had taught it to prefer. We call this an action-channel memory leak. Formally, let π(t∣q,M) denote an agent’s distribution over tools t in a catalog T given a query q and memory state M, let F(M,m*) denote a declared forget operator, and let M★ denote an oracle store from which m* and all of its derived traces have been removed. The leak is the total-variation distance between π under the forgotten store MF and π under M★. This paper contributes a three-layer leak taxonomy (store, shadow, action), an interventional audit built on masking, upweighting, and swapping retrieved memories, and Forget-Consistent Coupling (FCC) a reference monitor that withholds confirmation of a successful forget until the measured action-channel leak falls under a budget ε. We further specify ActLeak-Bench, an evaluation protocol addressing tool selection after forgetting, as distinct from tool-parameter deflection while a memory remains live. We situate this contribution relative to closely adjacent work on memory-driven tool-selection bias and behavioral unlearning verification, present the protocol, evaluation conditions, and pre-registered hypotheses, and discuss what is required to execute the protocol and what a small-scale pilot would look like.

DOI: https://doi.org/10.5281/zenodo.22787979

Published by: vikaspatanker