Simple Procedure Research Articles

Synthesis, characterization, and investigation the catalytic potential of diammonium phosphate modified with bismuth for the one-pot synthesis of 3,4-dihydropyrimidin-2(1H)-ones through a three-component reaction: An in-depth evaluation using green metrics

A straightforward synthesis of a novel catalyst, bismuth phosphate (Bi(NO3)3/DAP), was achieved using a co-precipitation method. The resulting material underwent thorough characterization employing various techniques, including X-ray diffraction, FTIR, scanning electron microscopy (SEM), and EDX. We investigated the application of Bi(NO3)3/DAP as a catalyst in the 3,4-dihydropyrimidin-2(1H)-ones reaction between urea, ethyl acetoacetate, and various aldehydes. The results demonstrated that the catalyst exhibited excellent catalytic performance, leading to the production of products with impressive yields (89–97 %) in just 15 min in an ethanol medium. Additionally, the heterogeneity of the reaction was confirmed through a hot filtration test. Notably, this catalyst presents notable benefits, such as its easy recovery and ability to be reused for a minimum of five successive cycles, a simple work-up procedure, and the attainment of high product yields. A sustainability evaluation based on green metrics using the E-factor, atom economy (AE), reaction mass efficiency (RME), and optimum efficiency (OE) revealed that the use of a catalyst in the Biginelli reaction enhances environmental sustainability.

Design of efficient alterable bandwidth FIR filterbank for hearing aid system

The lifestyle of any person depends on his ability to hear his surrounding sounds or voices. This is because each of our sense organs works interrelated. Without an ability to proper hearing, he/she cannot respond to the other person leading to a very less or no communication to the society. Although he has a good talent and knowledge within, he cannot be able to communicate or express unless he has a good hearing ability. Also, he faces emotive problems caused by a reduction in self-confidence. So, a requirement of designing an efficient hearing aid is much necessary to resolve the hearing loss problem. In this paper, design of an efficient alterable ten band Finite Impulse Response filter bank for the hearing aid is achieved. Among the various windowing techniques available, Hamming window is preferred to design the FIR filter owing to its relatively sharp main lobe width and also the first few lobes have good attenuation. In this filterbank, variability in the subband bandwidths is achieved by simply altering each subband's bandwidth and center frequency. Unlike fixed filterbank, the proposed design provides the advantage of matching most of the audiograms of different hearing-impaired persons more accurately with simple procedure leading to low cost and low hardware complexity. Also using an FIR filter in the filterbank leads to highly stable design. Thus, a design of highly qualitative filterbank compared to fixed bandwidth designs with high audiogram matching and less matching error is implemented.

Role of nano-magnetized Citrus X sinensis (orange) peels for decontamination of pendimethalin from aqueous resources: a comparative study of untreated and carbonaceous orange peels with nano-magnetized peels

Abstract Biosorption is a low-cost, environment friendly wastewater treatment method that involves a simple procedure for the removal of pesticides and their residues from wastewater. In the present investigation, untreated Citrus X sinensis peels (U-CXSP), activated carbon Citrus X sinensis peels (AC-CXSP) and nano-magnetized Citrus X sinensis peels (NM-CXSP) adsorbents were applied for the uptake of pendimethalin (PDM) from aqueous resources. The laboratory-prepared adsorbents were characterized using SEM, EDX, FTIR, VSM and XRD. Biosorption studies were carried out by varying different parameters, i.e., adsorbents dosage (0.1–0.5 g), time of contact (10–70 min), initial concentration of PDM (5–200 ppm), pH and temperature. The results showed that the removal efficiency of U-CXSP was increased from 97 to 114 mg/g for AC-CXSP adsorbent and increased from 97 to 111 mg/g for NM-CXSP adsorbent. Kinetics data obtained from this study well fitted with pseudo-second-order kinetic model. Adsorption isotherms were studied and the adsorption data well fitted with Langmuir and Freundlich models. Order of the adsorption efficiency is observed as follows: AC-CXSP > NM-CXSP > U-CXSP.

Comparison of competitive and sandwich immunochromatographic analysis in the authentication of chicken in meat products

Cheap chicken meat is often used as an undeclared substitute in meat products. In this study, two formats of the immunochromatographic assay (ICA) of immunoglobulins of class Y (IgY) as a biomarker for chicken authentication were developed. In both competitive ICA (cICA) and sandwich ICA (sICA), gold nanoparticles (GNP) were conjugated with anti-species antibodies. A simple procedure of sample preparation, which took only 30 min, was proposed. Test systems demonstrated high sensitivity and rapidity: visual limits of detection of IgY and assay durations were 12/14 ng/mL and 10/15 min for cICA and sICA, respectively. The absence of cross-reactivity with the mammalian species confirmed the high specificity of the test systems. Good applicability of the assays was confirmed for the detection of chicken in raw meat mixtures: as low as 3% and 0.2% (w/w) of chicken could be revealed in beef and pork by cICA and sICA, respectively. The influence of heat processing of meat-based products on immune recognition and, consequently, the analytical performance of the test systems was revealed. It was shown that sICA is preferable for the detection of IgY even in thermally processed meat. The proposed ICAs can be recommended for rapid on-site control of meat products’ composition.

On the Exact Solution of a Scalar Differential Equation via a Simple Analytical Approach

The existence of the advance parameter in a scalar differential equation prevents the application of the well-known standard methods used for solving classical ordinary differential equations. A simple procedure is introduced in this paper to remove the advance parameter from a special kind of first-order scalar differential equation. The suggested approach transforms the given first-order scalar differential equation to an equivalent second-order ordinary differential equation (ODE) without the advance parameter. Using this method, we are able to construct the exact solution of both the transformed model and the given original model. The exact solution is obtained in a wave form with specified amplitude and phase. Furthermore, several special cases are investigated at certain values/relationships of the involved parameters. It is shown that the exact solution in the absence of the advance parameter reduces to the corresponding solution in the literature. In addition, it is declared that the current model enjoys various kinds of solutions, such as constant solutions, polynomial solutions, and periodic solutions under certain constraints of the included parameters.

Fabrication of superhydrophobic (CuO-SiO2) nanocomposite coating for oil/water separation

ABSTRACT The presence of oil-contaminated water due to oil spill disasters or improper industrial waste dumping is now a worldwide danger to both human health and the sustainability of the environment.The use of superhydrophobic materials has attracted considerable attention in the field of oil-water separation, owing to the increasing demand for effective and economical oil-water separation techniques.A new, easy, and inexpensive flame treatment method was used to make a nanocomposite (CuO-SiO2) in order to improve its hierarchical structure (micro-nano).The anodisation process produced copper oxide (CuO) nanostructures (NSs) on a copper mesh. Subsequently, the nanostructures were modified by dip coating with a solution of room-temperature vulcanised silicone rubber (RTV-SR).The coated mesh demonstrated remarkable characteristics of superhydrophobicity and superoleophilicity, with a water contact angle (WCA) of (160 ± 1 ° ) and an oil contact angle (OCA) of (0 ° ), as determined during the measurement of the surface’s wetability. The coated mesh surface was characterised using X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), and energy dispersive spectroscopy (EDS).The successful separation of kerosene-water and diesel oil-water mixtures is accomplished by using a coated mesh in a simple filtration procedure. Furthermore, it has the capability to separate oils with a high efficiency of (99.8%) for kerosene and (87%) for diesel oil. It also has flux values of (7352.9 L.m -2 .h -1 ) for kerosene and (6112.9 L/m 2 .h) for diesel.

Crystallization and defects regulation of efficient perovskite solar cells via surface induced secondary grain growth with formamidine iodine treatment

Trap–mediated non–radiative loss is a major efficiency and stability obstale for solution–processed perovskite solar cells (PSCs). To address this issue, defect passivation using organic molecules has been identified as an effective strategy due to the ionic nature of the perovskite lattice. Herein, Ostwald ripening by using formamidine iodine (FAI) is reported to inhibit the carrier trap induced recombination via promoting secondary grain growth at perovskite surface. Based on secondary grain growth with FAI treatment, the graded passivation was presented caused by FA+ and I- from FAI. Moreover, the findings from time resolved photoluminescence and space charge–limited current technology indicate enhancements in the crystal quality. Consequently, this approach yielded a remarkable power conversion efficiency (PCE) of 20.62% for the FAI modified MAPbI3 photovoltaics, with significantly improved open–circuit voltage ratio of 3.10%, short–circuit density ratio of 6.11%, fill factor ratio of 9.46% and PCE ratio of 19.06%. Moreover, the device show the excellent stability. This study introduces simple and reproducible procedures for fabricating PSCs, which can be readily extended to diverse optoelectronic device applications.

Spectrophotometric resolution for quantitative analysis of aspirin and rivaroxaban combination therapy in biological fluids using simple and eco-friendly procedure

Patients diagnosed with symptomatic peripheral artery disease (PAD) in the lower extremities have a higher likelihood of suffering from major vascular events. Recently, FDA has approved the combination therapy of aspirin (ASP) and rivaroxaban (ROX) to reduce acute limb ischemia and other comorbidities in (PAD) patients. Zero order and ratio absorption spectra were employed in three simple and accurate spectrophotometric techniques (dual wavelength (DW), ratio difference (RD) and derivative ratio (1DD) for concurrent detection and quantification of ASP and ROX in their pure forms, lab synthetic mixtures and in biological fluid. Our approach involves careful parameter optimization, including solvent selection, sample volumes, and instrumental settings, to reduce the analysis environmental impact. The acquired recovery percentages of accuracy were within 98–102% for pure active pharmaceutical ingredients and 90–110% for pharmaceutical formulations and biological determinations. A comprehensive assessment was done to compare the three methods regarding their ease of use, linearity, sensitivity, conditions, and limitations. The specificity of the proposed methods was evaluated by analyzing the lab synthetic mixtures. The suggested spectrophotometric methods were validated in compliance with ICH guidelines to confirm the validity claims. Also, statistical analysis was done to compare the outcomes obtained from the suggested methods with those obtained from the official ones and they agreed with null hypothesis regarding accuracy and precision. Furthermore, a comprehensive assessment of the environmental sustainability of the developed method was carried out using the Analytical Greenness Calculator, AGREE algorithm. The selected drugs can be efficiently, safely and economically analyzed by the suggested methods in pharmaceutical and biological matrices with no pretreatment or preliminary separation steps and thereby increasing their greenness level.

A systematic review of the operative techniques for treating cubitus varus deformity in children.

A systematic review of the operative techniques for treating cubitus varus deformity in children was performed using research databases including PubMed and Embase. Outcome measurements included mean angular correction of the humerus-elbow-wrist angle, complications, revisions and outcome scores. A total of 45 papers and 911 patients were included. Lateral closing wedge osteotomy (LCWO) (427 patients) was the most common procedure and 5.56% of these patients experienced lateral condylar prominence. This technique had the highest revision rate at 3%. The step-cut osteotomy (111 patients) yielded zero postoperative infections or loss of motion. Distraction osteogenesis (92 patients) was the least common technique. Superficial pin tract infections occurred in 18% of patients and 88.04% of patients reported excellent results, the highest of any technique in this study. The infection rate of dome osteotomy (151 patients) was 9.45% and 4.72% of patients experienced loss of motion. 3D osteotomy (130 patients) had no infections, 87.78% of patients reported excellent outcomes, and 2.22% of patients reported poor outcomes, the lowest of all techniques. For unidimensional correction, LCWO provides a technically simple procedure and reasonable outcomes. Step-cut osteotomy has less lateral condylar prominence but is more complicated than LCWO. Distraction osteogenesis is a minimally invasive alternative to LCWO and step-cut osteotomy, but it has more superficial infections and can be bothersome to patients. For a multidimensional correction, 3D osteotomy is superior to dome osteotomy due to its lower infection rate and higher rate of functionally excellent outcomes.

Exploring Heterotropones and Examining Their Propensity to Undergo [4 + 2] Cycloadditions.

An efficient strategy to obtain a broad array of chiral and achiral heterotropones and their corresponding [4 + 2] cycloadducts is disclosed. This strategy enables access to unique heterotropones and intricate bicyclic structures in high yields and diastereoselectivities through a simple procedure and from easily accessible starting materials.

Facile Preparation of TICT@MOF Solids with Unprecedented PL Quantum Yields

AbstractLuminescent solids exhibit unique optical and electronic properties, and it is important to develop a simple experimental procedure to reduce the mass of weakly emissive hybrid inorganic–organic solids. The instant mixing of (1‐cyano‐2‐[α‐terthiophen‐2‐yl]‐vinyl)carboxylic acid (3TCC) and a metal–organic framework (MOF‐177; ZnO4(BTB)2; BTB = 1,3,5‐benzenetribenzoate) in an organic solvent, followed by evaporation of the solvent, produces solids with distinct photoluminescence (PL) properties, turning over the PL quantum yields (PLQY) of the generated 3TCC@MOF‐177 solids by 2‐ to 40‐fold compared to the 3TCC solution is demonstrated. The new solids are characterized by various methods and optical measurements. Contrarily to the trend in the photophysical results of 3TCC solutions, the anisotropic rotational times of 3TCC@MOF‐177 solids inversely correlate with the corresponding PLQY values depending on the protic solvent used in the initial preparation step in the following order: methanol>ethanol>butanol. This behavior is attributed to the complexation of 3TCC dye with metal clusters within the pores of MOF‐177 and hydrogen bonding of the CN group in the dye with the OH group in the linkers. These factors interplay with the kinetics of dye twisting. These observations reflect the potential of new solid luminescent architectures with remarkable PLQY that can be easily manufactured.

Special moment frame connections with shear-yielding haunches

Steel special moment frame connections with shear-yielding haunches can be used for seismic retrofit and for new construction. In this study, shear-yielding haunch connections were investigated through experimental testing and finite element analysis. Three specimens were tested, each with a W1000 × 591 beam and W1000 × 554 column. The cyclically loaded specimens completed cycles at 0.04 rad prior to low-cycle fatigue of the haunch plates. The monotonically loaded specimen reached 0.064 rad drift. The experimental specimens had 10 to 15% post-yield stiffness, and the fuses reached the ultimate material strength prior to tearing. M-factors for the connection were determined to be 4.7 for life safety and 6.3 for collapse prevention. Finite element models were used to quantify force transfer through the connection and to investigate the retrofit-specific detail. The experiments and finite element models confirmed that a relatively simple design procedure produced acceptable designs.

Recent development and engineering practices of space grid structures in China

Space grid structures are widely used in the field of structural engineering due to their good mechanical properties and simple construction procedures. This paper reviews the development of space grid structures and mainly introduces the development of space grid structures in China in recent years. Some typical applications of space grid structures are introduced and the technical developments are summarized. It shows that China not only has a large number of engineering applications of space grid structures, but also a rapid development of related technologies. Finally, some prospects for space grid structures are discussed.

On k-wave solutions of quasilinear systems of partial differential equations

In this paper, we establish a relation between two seemingly unrelated concepts for solving first-order hyperbolic quasilinear systems of partial differential equations in many dimensions. These concepts are based on a variant of the conditional symmetry method and on the generalized method of characteristics. We present the outline of recent results on multiple Riemann wave solutions of these systems. An auxiliary result concerning a modification of the Frobenius theorem for integration is used. We apply this result in order to show that the conditional symmetry method can deliver larger classes of multiple Riemann wave solutions, through a simpler procedure, than the one obtained from the generalized method of characteristics. We demonstrate that solutions can be interpreted physically as a superposition of k single waves. These theoretical considerations are illustrated by examples of hydrodynamic-type systems in (n+1) dimensions.

Synthesis of geopolymer composites using bauxite residue-based spheres as aggregate: Novel and eco-friendly strategy to produce lightweight building materials

In this study, and for the first time, highly porous red mud-based geopolymer spheres were produced, through a very simple and scalable procedure, and used as lightweight aggregate in the synthesis of geopolymer composites. To further demonstrate the potential of this unexplored route, a comparison with composites containing expanded perlite and expanded vermiculite was also performed. The sample produced with 85 vol% of spheres showed the lowest geometric density (0.84 g/cm3) amongst the studied composites, coupled with a suitable compressive strength (1.0 MPa), low thermal conductivity (175 mW/m K), and excellent thermal stability after exposure to 1000 °C for 2h. The much lower production temperature (80 °C), compared with the commercial expanded aggregates (above 650 °C), and the reuse of significant amounts of bauxite residue (strategy aligned with the circular economy) enables the production of eco-friendly lightweight aggregates for the building sector.

Indocyanine green fluorescence imaging: A novel adjunct to gastrointestinal surgery

Indocyanine Green (ICG) has been applied in medicine since the late 50s for cardiac output measurement, to study the anatomy of Retinal vasculature, and liver functional reserve before major hepatectomy in cirrhotic livers. The dye can be injected into the human bloodstream with practically no adverse effects. ICG fluorescence imaging is advantageous in being compatible with the biochemical characteristics of living tissues. ICG has been used in medical science for the last several decades. However, its use in surgery has recently been explored and has found vast applications in the surgical field. In particular, its use in Gastrointestinal (GI) surgery including hepatobiliary surgery has started to define new trends and techniques to guide the modern surgeon in both simple and complex procedures. In this review we thus explore in light of recent literature the potential uses of ICG in GI surgery.

Effectiveness and safety of intraoperative intraperitoneal 5-Fu drug implantation in patients with colorectal cancer: a retrospective cohort study

PurposeThe purpose of this clinical study was to evaluate the efficacy and safety of intraoperative chemotherapy (IOC) with intraoperative intraperitoneal implantation of 5-fluorouracil (5-FU) in colorectal cancer (CRC) patients.MethodsIn this study, 165 patients who underwent colorectal radical surgery were selected, of whom 111 in the experimental group received surgical treatment with an intraperitoneal 5-fluorouracil (5-FU) implantation. Fifty-four patients who did not undergo intraperitoneal implantation of 5-FU were matched to compare the progression-free survival (PFS) and overall survival (OS) with the former.ResultsWe also studied the differences in the changes of different biochemical indicators between the two groups before and after surgery, and there were significant differences in leukocytes, neutrophils, and lymphocytes before and after (P < 0.05), while for sodium ions, potassium ions, platelets, alanine transaminase, aspartate transaminase, creatinine, urea, and albumin, there were no significant differences. This may be related to the intraperitoneal chemotherapy implant entering the blood circulation. For 5-year OS, there were 85/111 (76.58%) in the 5-FU group (P = 0.013) and 35/54 (64.81%) in the control group; for 5-year PFS, there were 84/111 (75.68%) in the 5-FU group and 29/54 (53.70%) in the control group (P = 0.02). All the experimental groups were better than the control group with a significant difference in the experimental results.ConclusionFor CRC surgery patients, intraperitoneal implantation of slow-release 5-FU drugs, which is a safe and simple procedure, can improve the prognosis of the patients.Clinical trial registrationNo clinical trials were performed in the study.

Reinforcement of nanostructured polyacrylamide hydrogels through the generation of secondary physical network using the nanoparticles’ functional groups

The main drawback regarding hydrogels utilization in biomedical engineering is represented by their weak mechanical properties and it is often addressed either by using nanospecies as fillers or by generating secondary networks that strengthen the material. Our study validates a new synthesis route of obtaining double-network nanostructured materials making use of the functional groups of an adsorbed glyco-protein on carbon-based nanospecies. Following a simple procedure, the decorated nanospecies were embedded in a synthetic polymer and subsequently formed a secondary hydrogen-bond based network through incubation in natural polyphenol solutions of various concentrations. The natural macromolecule's adsorption was evaluated through FTIR and DLS measurements. When compared to the single-network nanostructured materials, the double-network hydrogels exhibited lower affinity to aqueous media and improved ability to dissipate energy upon mechanical stress, depending on the amount of the employed natural crosslinker. As a result of generating the second network through incubation in polyphenol aqueous solution, the surface storage and loss moduli exceed the values of the bulk ones, as indicated by rheology and nanoindentation tests. The properties of the double-network hydrogels can also be tailored towards more hydrophilic surfaces with increased roughness through the control of the supplementary crosslinker amount. Considering the studied physical-chemical properties, and especially their mechanical characteristics, the obtained materials hold great promise for biomedical applications, particularly for the fabrication of scaffolds for wound dressing, soft or low load bearing tissue regeneration and repair.

K2CO3-Mediated Intramolecular Oxa-Michael Cyclization of α,β-Unsaturated Ketoximes: Synthesis of Densely Arene-Substituted 2-Isoxazolines Bearing a Quaternary Center

AbstractAn efficient K2CO3-mediated intramolecular oxa-Michael cyclization of β,β-diarylated α,β-unsaturated ketoximes is described. This methodology allows access to arene-rich 2-isoxazoline derivatives bearing a quaternary center in excellent yields with an operationally simple experimental procedure. Deuterium-scrambling experiments were carried out to shed light on the reaction pathway. To demonstrate the synthetic utility of the method, a large-scale synthesis and Ullmann-type C–N bond-formation reaction between pyrazole and dibrominated isoxazoline was performed.

A green-footprint approach for parallel multiclass analysis of contaminants in roasted coffee via LC-HRMS

The development and validation of a simple, comprehensive, and environment-friendly procedure to determine pesticide residues, naturally occurring and processing contaminants in roasted coffee is presented. A solid-liquid extraction of pesticides and mycotoxins with ethyl acetate and the concurrent partition of acrylamide to an aqueous phase follows a parallel analytical strategy that requires a single analytical portion to determine contaminants that are typically analyzed by dedicated single residue methods. The partition rules the lipids out of the aqueous extract before an “in-tube” dispersive solid phase microextraction (dSPME) for acrylamide retention. This is followed by the elution with buffer prior to injection. This extract is independently introduced into the system front end followed by the injection of the compounds from the organic phase, yet all spotted in the same run. A novel liquid chromatography high-resolution mass spectrometry (LC-HRMS) method setup enables the quantification of 186 compounds at 10 µg/kg, 226 at 5 µg/kg, and the acrylamide at 200 µg/kg for a total of 414 molecules, with acceptable recoveries (70–120%) and precision (RSD < 20%) making this strategy significantly faster and cost-effective than the dedicated single residue methods. Even though the presence of chlorpyrifos, acrylamide, and ochratoxin A was confirmed on samples of different origins, the findings were below the limit of quantification. During the storage of raw coffee, no proof of masking of OTA was found; however, condensation with glucose was evidenced during thermal processing experiments with sucrose by using stable isotope labeling (SIL). No detected conjugates were found in roasted nor in commercial sugar-added torrefacto samples, an industrial processing usually carried out above the decomposition temperature of the disaccharide.Graphical abstract