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Applying a low surface energy water-repellent finish agents to fabric is one of the effective ways to make it obtain water-repellent function. Water-repellent finish agents are mainly divided into two categories, fluorinated and non-fluorinated, and fluorinated water-repellent agents will be gradually banned because of environmental protection issues. Organosilicons, polyacrylates, and dendritic macromolecules are the most studied types of non-fluorinated water-repellent agents, but there are some problems in the preparation and use of these non-fluorinated water-repellent agents. Here, using 58 # fully refined paraffin wax as raw material, the paraffin wax was modified by no catalytic oxidation modification method to improve its emulsification performance. The oxidation-modified paraffin wax was used as raw material to prepare a stable, uniform and good fluidity water-repellent emulsion. The oxidation-modified paraffin wax emulsion was used as a water-repellent agent, and waterborne polyurethane (WPU) was used as a crosslinking agent to finish pure cotton fabrics and polyester/cotton-blended fabrics. After water-repellent finish, the contact angle of pure cotton fabric was 135° and that of polyester/cotton-blended fabric was 145°. This study provides a useful way for exploring non-fluorinated water-repellent agent with low cost and simple production process.

Membrane fouling is a serious handicap of membrane-based separation, as it reduces permeation flux and hence increases operational and maintenance expenses. Polyurethane–paraffin wax (PU/PW) nanocapsules were integrated into the polyethersulfone membrane to manufacture a composite membrane with higher antifouling and permeability performance against humic acid (HA) and bovine serum albumin (BSA) foulants. All manufactured membranes were characterized by scanning electron microscopy (SEM), scanning electron microscopy-energy dispersive spectrometry (SEM-EDS), and contact angle. The contact angle of the pristine polyethersulfone (PES) membrane was measured 73.40 ± 1.32. With the embedding of nanocapsules, the contact angle decreased to 64.55 ± 1.23 for PES/PU/PW 2.0 wt%, and the pure water flux of all composite membranes increased when compared to pristine PES. The pristine PES membrane also has shown the lowest steady-state fluxes at 45.84 and 46.59 L/m2h for BSA and HA, respectively. With the increase of PU/PW nanocapsule ratio from 0.5 to 1.0 wt%, steady-state fluxes increased from 51.96 to 71.61 and from 67.87 to 98.73 L/m2h, respectively, for BSA and HA. The results depicted that BSA and HA rejection efficiencies of PU/PW nanocapsules blended PES membranes increased when compared to pristine PES membranes.

The research article addresses the effect of multi-wall carbon nanotube (MWCNT) and nano-boron nitride (NBN) hybrid composite powders on thermal properties of the paraffin wax for thermal storage applications. Five different phase change material (PCM) samples were prepared with 100 paraffin wax, 99.5 paraffin wax + 0.5 MWCNT, 99.5 paraffin wax + 0.5 BN, 99 paraffin wax + 0.5 MWCT + 0.5 BN and 98 paraffin wax + 1 MWCNT + 1 BN mass percentage compositions. The size of the secondary particles MWCNT and NBN was assessed using transmission electron microscope (TEM). After PCM preparation, the morphology and distribution of the secondary particles were evaluated using field emission scanning electron microscope (FE-SEM). The phase change of MWCNT and NBN was evaluated using X-ray diffraction (XRD) technique. Differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and thermal conductivity tests were carried out on the PCMs to assess physical and thermal properties. The results revealed that hybrid nano-composite powders with paraffin wax provide better thermal conductivity of paraffin wax which increased from 0.18 to 0.31 W m −1 K −1 . However, the distribution of MWCNT and NBN extended the thermal degradation of paraffin wax and solidification temperature. Increasing the mass % of MWCNT and NBN reduced the melting point of paraffin wax from 64.70 to 62.52 °C. Further, the solidification temperature of paraffin wax increased while increasing the mass % of MWCNT and NBN from 56.01 to 60.13 °C. This research revealed that thermal properties of paraffin wax were significantly increased with the increment of mass % of composite powders (MWCNT and NBN) addition.

In various countries worldwide, solar water heater systems (SWHs) are utilized as devices that harness solar energy as a primary energy source. This study investigates the performance of SWHs numerical simulation by integrating phase change material (PCM) paraffin wax onto an absorber plate collector at the bottom for thermal storage. This study presents the thermal performance of a SWHs that uses an absorber plate with PCM for thermal energy storage. In this test, four variations of the model tested, namely a) standard flat plate (SFP), b) standard flat plate with PCM storage thickness 10mm (SFP+PCM 10mm), c) standard flat plate with PCM storage thickness 7mm (SFP+PCM 7mm), and d) standard flat plate with PCM storage thickness 4mm (SFP+PCM 4mm), were investigated using numerical simulation. Initially, an analytical investigation was conducted to examine the material qualities of paraffin wax utilised for phase change material (PCM) storage. The SWH systems were subsequently imported and simulated under three different levels of continuous solar radiation: 400 W/m 2 700 W/m 2 and 1000 W/m 2 . The simulation incorporates the use of computational fluid dynamics (CFD) tools. The results of the study revealed that the collector of the SWH system, which utilised an absorber plate containing phase change material (PCM) storage, demonstrated exceptional performance. Models with a thickness of 7mm PCM or SFP+PCM 7mm have the highest efficiency compared to other models with an efficiency value of 64%. There is a 3-4% increase in efficiency with variations in models that use PCM thermal storage compared to models that do not use PCM thermal storage.

This study aimed to address the issue of high-temperature challenges in asphalt pavement by developing two types of phase change materials (PCMs) for temperature control. Encapsulated paraffin wax particles (EPWP) and encapsulated myristic acid particles (EMAP) were synthesized using acid-etched ceramsite (AECS) as the carrier, paraffin wax (PW) or myristic acid (MA) as the core material, and a combination of epoxy resin and cement as the encapsulation material. The investigation encompassed leakage tests on PCMs; rutting plate rolling forming tests; SEM, FTIR, XRD, and TG-DSC microscopic tests; as well as heat storage and release tests and temperature control assessments using a light heating device. The study revealed the following key findings. Both types of PCMs exhibited no PCM leakage even under high temperatures and demonstrated low crushing ratios during rut-forming tests. Microscopic evaluations confirmed the chemical stability and phase compatibility of the constituents within the two types of PCMs. Notably, the phase change enthalpies of EPWP and EMAP were relatively high, measuring 133.31 J/g and 138.52 J/g, respectively. The utilization of AECS as the carrier for PCMs led to a substantial 4.61-fold increase in the adsorption rate. Moreover, the PCMs showcased minimal mass loss at 180 °C, rendering them suitable for asphalt pavement applications. The heat storage and release experiments further underscored the PCMs’ capacity to regulate ambient temperatures through heat absorption and release. When subjected to light heating, the maximum temperatures of the two types of phase change Marshall specimens were notably lower by 6.6 °C and 4.8 °C, respectively, compared to standard Marshall specimens. Based on comprehensive testing, EPWP displayed enhanced adaptability and demonstrated substantial potential for practical implementation in asphalt pavements.

For the realization of bioassay with complex fluidic manipulation and logic operation on lab-on-a-disc platform, we present an active integrated centrifugal microfluidic chip based on the on-board control of wax valves within a multilayer complex chip. The multilayer hybrid structure including a microfluidic layer and a printing circuit board (PCB) layer utilizes the digital logic of electronic system to control the logic of liquid flow in microfluidic layer. The coupling mechanism between both layers is based on heat transfer, namely, the heating resistors in PCB layer are used to melt and open the paraffin wax valves in microfluidic layer. Without the limitation of surface tension-dependent valves, the application of active valve could be freely designed, which can largely extend the ability of integration on microfluidic chip. Many complex functional units including liquid sequential loading and switching of liquid flow are demonstrated. As an application, we also present a multilayer complex chip for plasmid DNA extraction based on our platform. In a word, our active centrifugal microfluidic platform provides a solution for the integration of complex bioassay on rotating disc, which has great potential in the applications of point-of-care diagnostics (POC).

In order to enhance the application of thermoregulated materials, magnetic phase change microcapsules were prepared using a self-assembly method. Paraffin wax was chosen for its fine thermoregulation properties as the core material, while Fe3O4 nanoparticles doped in calcium carbonate served as the hybrid shell material. The microcapsules were then blended with sodium alginate and processed into seaweed fibers through wet spinning. The microstructure, thermal, and magnetic properties of the microcapsules were analyzed using scanning electron microscopy, energy dispersive X-ray spectroscopy, a laser particle size analyzer, an X-ray diffractometer, a differential scanning calorimeter, a thermogravimetric analyzer, and a vibrating sample magnetometer. The thermoregulation of the fibers was evaluated using a thermal infrared imager. The results indicated that the microcapsules had a uniform size distribution and good thermal properties. When the mass fraction of Fe3O4 nanoparticles was 8%, the microcapsules exhibited a saturation magnetization of 2.44 emu/g and an enthalpy value of 94.25 J/g, indicating effective phase change and magnetic properties. Furthermore, the thermoregulated seaweed fibers showed a high enthalpy value of 19.8 J/g with fine shape, offering potential for developing multifunctional fiber products.

In metal fused deposition modeling (FDM), performance is governed by feedstock formulation, most critically the metal solid loading, while binder selection is constrained by environmental impacts and limited recyclability. This study investigates the development and performance of highly filled 17-4PH stainless steel (17-4PH) feedstocks formulated with a low-molecular-weight polymer binder system, specifically designed for FDM in metal additive manufacturing (AM). The binder system, composed of low-cost, recyclable paraffin wax and stearic acid, was used to prepare feedstocks containing 93.0–96.0 wt.% metal powder. Rheological analysis indicated that intermediate powder loadings (95.0–95.5 wt.%) yielded optimal shear-thinning behavior, essential for stable extrusion during printing. Printing trials identified 95.5 wt.% as the critical powder loading, delivering superior print fidelity and structural integrity relative to both under-filled (93.0–94.5 wt.%) and overfilled formulations. Green part characterization revealed increased density and flexural modulus with rising powder content, while thermal debinding and sintering trials indicated enhanced thermal stability and dimensional retention at higher loadings. The as-sintered specimens from the 95.5 wt.% feedstock achieved a relative density (RD) of 96.5% and significantly improved mechanical performance, including an ultimate tensile strength (UTS) of 758 MPa and 5.2% elongation, clearly outperforming the 95.0 wt.% variant. Tribocorrosion testing further validated these improvements, with the higher-density samples showing a lower coefficient of friction and a reduced wear coefficient of 2.1 × 10−5 mm3·(N·m)−1 in 3.5% NaCl solution.

Thermal energy storage technology is an important topic, as it enables renewable energy technology to be available 24/7 and under different weather conditions. Phase changing materials (PCM) are key players in thermal energy storage, being the most economic among those available with adjustable thermal properties. Paraffin wax (PW) is one of the best materials used in industrial processes to enhance thermal storage. However, the low thermal conductivity of PW prevents its thermal application. In this study, we successfully modified PW based on multi-walled carbon nanotubes (MWCNT) with different concentrations of TiO2—3, 5 and 7 wt.%. The morphology of PCM and its relationship with the chemical structure and stability were characterized using scanning electron microscopy (SEM), Fourier transform infrared (FTIR) and Thermogravimetric analysis (TGA). As a result, the composites achieved a highest latent heat enthalpy of 176 J/g, in addition to enhanced thermal stability after 15 thermal cycles, and reliability, with a slight change in latent heat observed when using a differential scanning calorimeter (DSC). The thermal conductivity of the composites could significantly be enhanced by 100%. Compared to pure paraffin, the PCM composites developed in this study exhibited an excellent preference for thermal energy storage and possessed low cost, high reliability, and phase change properties.

Introduction A cure for osteoarthritis is unknown. However, lessen the discomfort and symptoms by implementing several lifestyle changes and therapies. Reducing discomfort, enhancing joint mobility, and halting more joint injury are the goals of therapy. Purpose To evaluate the combined effect of wax therapy, Ultrasound therapy, Interferential therapy, stretching and resisted exercises when compare to Pulsed shortwave diathermy and resisted exercise among bilateral osteoarthritis knee patients. Methods This was a randomized controlled trial conducted on participant aged above 45 with Bilateral knee osteoarthritis, in the Outpatient Physiotherapy Department, B.K.L Walawalkar Rural Medical Hospital, Sawarde, Maharastra. The outcome measure used were Visual Analoue Scale for pain, Goniometer for bilateral knee flexion and extension Range of Motion, and Western Ontario and McMaster Universities Osteoarthritis Index. Result There were significant improvements in the experimental group and control group in terms of the pre-test and post-test scores for the Pain by VAS ( p  = 0.000 < 0.05), average both knee flexion ROM by goniometry ( p  = 0.000 < 0.05), average both knee extension ROM by goniometry ( p  = 0.000 < 0.05), speed 50 Meters (in distance/time) ( p  = 0.000 < 0.05) and WOMAC by physiotherapy ( p  = 0.000 < 0.05). Conclusion The combined effect of Paraffin Wax Therapy, Ultrasound therapy, Interferential therapy, stretching, and resisted exercises in bilateral osteoarthritis knee patients significantly relieved the knee pain with increased knee flexion/extension range of motion, increased speed of walking for 50 m on floor and improved WOMAC Score when compare to pulsed shortwave diathermy with resisted exercises.