Manufacture Of Materials Research Articles

Recycling Materials for Sustainable DNA Origami Manufacturing.

DNA origami nanotechnology has great potential in multiple fields including biomedical, biophysical, and nanofabrication applications. However, current production pipelines lead to single-use devices incorporating a small fraction of initial reactants, resulting in a wasteful manufacturing process. Here, we introduce two complementary approaches to overcome these limitations by recycling the strand components of DNA origami nanostructures (DONs). We demonstrate reprogramming entire DONs into new devices, reusing scaffold strands. We validate this approach by reprogramming DONs with complex geometries into each other, using their distinct geometries to verify successful scaffold recycling. We reprogram one DON into a dynamic structure and show both pristine and recycled structures display similar properties. Second, we demonstrate the recovery of excess staple strands postassembly and fold DONs with these recycled strands, showing these structures exhibit the expected geometry and dynamic properties. Finally, we demonstrate the combination of both approaches, successfully fabricating DONs solely from recycled DNA components.

UV-radiation manufacturing of natural macromolecular products salecan and tannic acid-based functional gel material as superadsorbent for toluidine blue remediation

Adsorbent materials constructed from natural macromolecular products are favored because of their wide range of sources, biodegradability, and environmental friendliness. Salecan is a novel extracellular polysaccharide with ideal physicochemical and biological activities. Here, we have designed a polymer gel through UV-initiated polymerization of [2-(Methacryloyloxy) ethyl] dimethyl-(3-sulfopropyl) ammonium hydroxide (SBMA) in the mixture of salecan and tannic acid. Photopatterned polymerization process allowed in situ formation of gel adsorbent in a mild reaction condition with energy-efficient manner. Batch experiments for toluidine blue (TB) adsorption were carried out as a function of initial dye concentration, solution pH, contact time, and gel dosage to examine the adsorption capacity, potential mechanism, and removal efficiency. Adsorption behavior exhibited a pH-dependence pattern, which was closely related to their swelling and morphological properties. Adsorption process was in conformity to pseudo-second-order kinetic and Langmuir isotherm models, unlocking a chemical adsorption behavior and monolayer-type removal. The maximum adsorption was 490.2 mg/g, which could be considered a superiorly competing value. Additionally, the UV-gel still showed desirable recyclability and maintained the adsorption effectiveness over 95 % after five regeneration cycles. This study opened up new prospects in preparing high performance adsorbent for TB decontamination and laid the foundation for polysaccharide-based adsorption material research.

Improving Continuous Loss-in-weight Feeding Accuracy by a Novel Hopper Design

PurposePowder feeding is a vital unit operation in the continuous manufacturing of pharmaceutical products. Loss-in-weight twin-screw feeders are commonly used in continuous manufacturing lines. The feeding performance, i.e., the accuracy and consistency of feeding, influences the content uniformity of the final drug product. In this study, a redesigned hopper for K-Tron KT20 twin-screw feeder was designed, implemented, and investigated to improve feeding performance. The basic idea was to design the hopper in such a way that the stresses on top of the screw entrance are independent of the fill level.MethodsOur study compared the novel system to that of the original cylindrical hopper. The effect of the redesigned hopper on the start-up, the process’ sensitivity to refill level, and the refill portion size were studied. A free-flowing, barely compressible powder and a compressible blend were used in this study to evaluate the feeding performance and the refill effects.ResultsWhen using compressible powders, the results showed a larger process window for refilling in the redesigned hopper and a lower refill-level sensitivity compared to the original hopper.ConclusionThe homogenization of stresses in the redesigned hopper allowed operating at lower refill levels, and variability, especially due to refilling, was reduced. This study demonstrates novel design approaches for successfully implementing hard-to-feed materials in continuous manufacturing.

Uncertainty quantification of acoustic metamaterial bandgaps with stochastic material properties and geometric defects

Acoustic metamaterials are a subject of increasing study and utility. Through designed combinations of geometries with material properties, acoustic metamaterials can be built to arbitrarily manipulate acoustic waves for various applications. Despite the theoretical advances in this field, however, acoustic metamaterials have seen limited penetration into industry and commercial use. This is largely due to the difficulty of manufacturing the intricate geometries that are integral to their function and the sensitivity of metamaterial designs to material batch variability and manufacturing defects. Capturing the effects of stochastic material properties and geometric defects requires empirical testing of manufactured samples, but this can quickly become prohibitively expensive with higher precision requirements or with an increasing number of input variables. This paper demonstrates how uncertainty quantification techniques, and more specifically the use of polynomial chaos expansions and spectral projections, can be used to greatly reduce sampling needs for characterizing acoustic metamaterial dispersion curves. With a novel method of encoding geometric defects in a 1D, interpretable, resolution-independent way, our uncertainty quantification approach allows for both stochastic material properties and geometric defects to be considered simultaneously. Two to three orders of magnitude sampling reductions down to ∼100 and ∼101 were achieved in 1D and 7D input space scenarios, respectively. Remarkably, this reduction in sampling was possible while preserving accurate output probability distributions of the metamaterial performance characteristics (bandgap size and location).

Wafer-scale fabrication of InGaP-on-insulator for nonlinear and quantum photonic applications

The development of manufacturable and scalable integrated nonlinear photonic materials is driving key technologies in diverse areas, such as high-speed communications, signal processing, sensing, and quantum information. Here, we demonstrate a nonlinear platform—InGaP-on-insulator—optimized for visible-to-telecommunication wavelength χ(2) nonlinear optical processes. In this work, we detail our 100 mm wafer-scale InGaP-on-insulator fabrication process realized via wafer bonding, optical lithography, and dry-etching techniques. The resulting wafers yield 1000 s of components in each fabrication cycle, with initial designs that include chip-to-fiber couplers, 12.5-cm-long nested spiral waveguides, and arrays of microring resonators with free-spectral ranges spanning 400–900 GHz. We demonstrate intrinsic resonator quality factors as high as 324 000 (440 000) for single-resonance (split-resonance) modes near 1550 nm corresponding to 1.56 dB/cm (1.22 dB/cm) propagation loss. We analyze the loss vs waveguide width and resonator radius to establish the operating regime for optimal 775–1550 nm phase matching. By combining the high χ(2) and χ(3) optical nonlinearity of InGaP with wafer-scale fabrication and low propagation loss, these results open promising possibilities for entangled-photon, multi-photon, and squeezed light generation.

Enhancing Tin Dioxide Anode Performance by Narrowing the Potential Range and Optimizing Electrolytes

Tin dioxide (SnO2) is a low-cost and high-capacity anode material for lithium-ion batteries, but the fast capacity fading significantly limits its practical applications. Current research efforts have focused on preparing sophisticated composite structures or optimizing functional binders, both of which increase material manufacturing costs. Herein, we utilize pristine and commercially available SnO2 nanopowders and enhance their cycling performance by simply narrowing the potential range and optimizing electrolytes. Specifically, a narrower potential range (0–1 V) mitigates the capacity fading associated with the conversion reaction, whereas an ether-based electrolyte further suppresses the volume expansion related to the alloy reaction. Consequently, this SnO2 anode delivers a promising battery performance, with a high capacity of ~650 mAhg−1 and stable cycling for 100 cycles. Our work provides an alternative approach to developing high-capacity and long-cycling metal oxide anode materials.

Klasterisasi Penggunaan Ban dengan Cost Per Kilometer Terendah pada PT. PL menggunakan Metode K-Means

Established in 1969, PT. Puninar has grown to become one of Indonesia's leading logistics companies. The company provides a broad range of logistics solutions through its subsidiaries, encompassing material management, manufacturing, warehousing, distribution, customs services, freight forwarding, and post-delivery operations. After fuel, tires represent the second-largest expenditure for the company. Proper tire management can reduce maintenance costs, making it a key cost-reduction strategy in the logistics sector. This study utilizes data mining techniques, specifically the K-means method, to analyze and classify tires based on travel distance and the lowest cost per kilometer, enabling monthly cost monitoring. PT. Puninar allocates approximately two billion rupiah per month for tire inventory due to its fleet of over seven hundred trucks. The company currently employs various tire brands, including Bridgestone, Doublecoin, Effiplus, Chengsang, and others, with varying levels of durability.

Interpretation of Chemical Compositions and Making Techniques for Ancient Glass Beads from Suchonri Tomb Complex in Gongju, Korea

The Suchonri tomb complex in Uidang of Gongju has been excavated several times, and the remains and artifacts from various periods have been unearthed. Tomb No. 8, known as a Baekje Kingdom, collected a large quantity of blue-colored glass beads, quartz bead and gold-gilded glass beads. In this study, we analyzed the occurrences, internal textures and chemical compositions of representative glass beads, and interpreted the making techniques based on the study. As a result, quartz bead, which are different from glass, were confirmed, and the glass beads were classified into potassium, sodium and gold-gilded beads. The internal texture of the glass beads contained a mixture of bubbles and unmelted additives. The additives consisted of fluxes, stabilizers and colorants compositions, and were observed in various crystals and shapes. Based on internal textures, arrangement of bubbles and shape of impurities within the glass beads, it seems that various making techniques such as the winding, the drawing and the molding methods were applied. In this way, the glass beads used in a single location have slightly different characteristics suggests the diversity of the manufacturing site, materials used and producers, as well as the possibility of external introduction. It can also be interpreted that the beads were likely procured and assembled for the funeral rites to serve the purpose of the interred individual.

FeSnO3/rGO nanocomposite electrode development for supercapacitor application

The manufacturing of electrode materials that are both highly efficient and cost-effective is crucial for energy storage systems. Because of their remarkable performance, nanocomposite materials are a good choice for creating energy storage systems. And the present study contains the fabrication of FeSnO3 and FeSnO3/rGO nanocomposite by hydrothermal approach. To assess electrochemical behavior of FeSnO3 and FeSnO3/rGO nanocomposite number of analytical tools such as galvanostatic charge-discharge (GCD), electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV) and chronoamperometry (CA) were employed. FeSnO3/rGO nanocomposite demonstrate specific capacitance (Csp) 1342.02 F/g and energy density (Ed) was 88.74 Wh/kg at a power density (Pd) of 345 W/kg at a current density of 1.0 A/g. The charge transfer resistance (Rct) of FeSnO3/rGO nanocomposite was found to be Rct = 0.43 Ω which was determined from Nyquist plot as well as showed cycling stability even after remains 5000th cycles. The addition of rGO increased the specific capacitance as well as surface area rise total number of active sites which allows electrolyte and electrode surface to make ideal connection for quick electrolyte ion diffusion. In accordance with the obtained findings, the FeSnO3/rGO nanocomposite is convincing capacitive electrode material for energy storage devices the future.

Polymer-Based Extracting Materials in the Green Recycling of Rare Earth Elements: A Review.

Rare earth elements (REEs) are becoming increasingly important in the development of modern and green energy technologies with the demand for REEs predicted to grow in the foreseeable future. The importance of REEs lies in their unique physiochemical properties, which cannot be reproduced using other elements. REEs are sourced through mining, with global exploration of additional commercially viable mining sites still ongoing. However, there is a growing need for recycling of REEs due to the current supply of REEs not matching the growing demand, the environmental impact of REE mining and processing (the so-called "balance problem"), and the generation of large volumes of harmful electronic waste (e-waste). Industrial REE processing is mainly carried out by hydrometallurgy processes, particularly solvent extraction (SX) and ion exchange (IX) technologies. However, these methods have a significant environmental impact due to their intensive use of harmful and nonsustainable reagents. This Review highlights the development of approaches involving polymer-based extracting materials for REE manufacturing as more sustainable alternatives to current industrial REE processing methods. These materials include supported liquid membranes (SLMs), solvent impregnated resins (SIRs), macro and micro capsules, polymer inclusion membranes (PIMs), and micro polymer inclusion beads (μPIBs). Polymer-based extracting materials have the advantage of more economical regent usage while applying the same extractants used in commercial SX, enabling applications analogous to the current industrial process. These materials can be fabricated by a variety of methods in a diverse range of physical formats, with the advantages and disadvantages of each material type described and discussed in this Review along with their applications to REE processing, including e-waste recycling and mineral processing.

TAFENet: A Two-Stage Attention-Based Feature-Enhancement Network for Strip Steel Surface Defect Detection

Strip steel serves as a crucial raw material in numerous industries, including aircraft and automobile manufacturing. Surface defects in strip steel can degrade the performance, quality, and appearance of industrial steel products. Detecting surface defects in steel strip products is challenging due to the low contrast between defects and background, small defect targets, as well as significant variations in defect sizes. To address these challenges, a two-stage attention-based feature-enhancement network (TAFENet) is proposed, wherein the first-stage feature-enhancement procedure utilizes an attentional convolutional fusion module with convolution to combine all four-level features and then strengthens the features of different levels via a residual spatial-channel attention connection module (RSC). The second-stage feature-enhancement procedure combines three-level features using an attentional self-attention fusion module and then strengthens the features using a RSC attention module. Experiments on the NEU-DET and GC10-DET datasets demonstrated that the proposed method significantly improved detection accuracy, thereby confirming the effectiveness and generalization capability of the proposed method.

Comparative calculation of expeses for lashing stack of packaged lumber by tiers and unbroken

The article gives a brief description of the stack of packaged lumber, requirements for its laying and lashing. It is describing the tiers method of laying and lashing packaged lumber, as well as its main fundamental differences from the unbroken method of lashing. Comparative cost calculations are considered and presented for lashing stack of packaged lumber by tiers and unbroken methods. It is described the technique of lashing the stack with the tiers method. It is comparing number of materials for manufacture of lashing, the difference in the expenditure of materials for manufacture of wires, required time for lashing of stack. It is described the possibility of avoiding expenses with the tiers lashing for additional lashing at several ports of discharging. It is also describing and analyzes the amount of time required for lashing of stack with different methods exactly after completion of loading.

Space–time topology optimization for anisotropic materials in wire and arc additive manufacturing

Wire and Arc Additive Manufacturing (WAAM) has great potential for efficiently producing large metallic components. However, like other additive manufacturing techniques, materials processed by WAAM exhibit anisotropic properties. Assuming isotropic material properties in design optimization thus leads to less efficient material utilization. Instead of viewing WAAM-induced material anisotropy as a limitation, we consider it an opportunity to improve structural performance. This requires the integration of process planning into structural design. In this paper, we propose a novel method to utilize material anisotropy to enhance the performance of structures both during fabrication and in their use. Our approach is based on space–time topology optimization, which simultaneously optimizes the structural layout and the fabrication sequence. To model material anisotropy in space–time topology optimization, we derive the material deposition direction from the gradient of the pseudo-time field, which encodes the fabrication sequence. Numerical results demonstrate that leveraging material anisotropy effectively improves the performance of intermediate structures during fabrication as well as the overall structure.

Thermal performance and Feasibility Study Using a Straw-Based Thermal Insulation in Geothermal systems

Straw is the part of the stem (or stubble) of certain grasses, known as "straw cereals", and is most often a by-product or waste product of cereal production. In northern Algeria, it is produced in all cereal growing regions. It is generally used for animal feed. In this study, straw waste is used as a bio-material for thermal insulation in bioclimatic constructions and especially in geothermal applications, and the thermal insulation needs in a geothermal system is discussed. Furthermore, thermal performance of wheat straw aggregates bio-based material is tested for several thicknesses until stable results are achieved, using conduction heat transfer tests or heating flat plate. This method is based on the temperature difference measuring across the sample (inlet and outlet) and finally, compared it with other commercial geothermal insulation materials. Obtained results give us an idea of the energy gains to be expected from the bio-based materials manufacture to be used in geothermal systems comparing to conventional materials. It is noted that, the optimum thickness of the insulation material based on straw is 2cm, giving a temperature gradient around 9°C versus 16°C for conventional materials. Straw organic waste material is a promising candidate as an alternative insulating material for low-carbon and green buildings targets. Which are in line with the objectives set by the Algerian government as part of the fight against climate change, in particular the development of renewable energies, the promotion of energy efficiency as well as clean technologies and waste recycling.

A Study on Two-Phase Flow with High Viscosity and Low Surface Tension Liquid in a 40-Degree Inclined Mini Channel

There are numerous applications of two-phase flow in mini pipes, including electronics cooling systems, microreactors in the chemical industry, and material development and manufacturing. This application requires a thorough understanding and is supported by complete data and information. However, the data and information are currently limited. Experimental research has been carried out on flow patterns, void fractions, and two-phase flow pressure gradients in small pipes. This study aims to obtain primary data on the subject. Dry air and a mixture of 67% distilled water, 30% glycerin, and 3% butanol represent the gas and liquid phases, respectively. The addition of butanol and glycerin each aims to reduce surface tension and improve the viscosity of the liquid phase, respectively. The density, kinematic viscosity, and surface tension of the liquid were 1,080.4 kg/m3, 2,368 mm2/s, and 38.6 mN/m, respectively. The test section was a 1.6 mm diameter glass pipe equipped with an optical correction box. The gas superficial velocity (JG) ranged from 0.025 to 66.3 m/s, whereas liquid superficial velocity (JL) varied from 0.033 to 4.935 m/s. The experiment was conducted under adiabatic conditions. Plug, slug-annular, annular, disperse bubbly, and churn flow patterns emerged, while separated flow was not discovered. For plug, slug-annular, and dispersed bubbly flows, the increase of JG proportionally affected the void fraction. However, for churn and annular flows, no particular relationship existed between JG and void fraction due to the slip between the real velocities of the gas and the liquid. The pressure gradient rose as JG and JL increased.

Cold sintering of α- and γ-modifications of aluminum oxohydroxides: A low-temperature route to porous corundum ceramics

Objectives. To obtain porous corundum ceramics using an innovative cold sintering process starting from different phase modifications of aluminum oxohydroxide — boehmite γ-AlOOH and diaspore α-AlOOH; to study the phase and structural properties of the resulting materials; and to assess their permeability to water.Results. Cold sintering enables the formation of single-phase corundum ceramics with an open porosity of 47.9% directly from the initial boehmite powder with the addition of 5 wt % corundum in the presence of 20 wt % water at a temperature of 450°C, mechanical pressure of 220 MPa, and isothermal exposure for 30 min. Under the same conditions of cold sintering, a mixture of diaspore and boehmite was transformed into α-AlOOH ceramics. This then turned into corundum with an open porosity of 39% when calcined in air at 600°C for 1 h. The resulting materials had permeability for pure water above 5000 L/(m2∙h∙bar).Conclusions. Cold sintering is a promising approach to producing porous corundum ceramics which can be used in filtration systems. Compared to traditional ceramic technology, the new approach reduces energy, time, and labor costs in the material manufacturing. It also eliminates the need to use auxiliary substances (binders, pore-forming agents, etc.).

Internal fit and marginal adaptation of all-ceramic implant-supported hybrid abutment crowns with custom-milled screw-channels on Titanium-base: in-vitro study

BackgroundAdvancements in digital dentistry helped in custom-milling screw-channels in implant-supported restorations; however, the fit of these restorations is still unclear especially for contemporary computer aided designing/computer aided manufacturing (CAD/CAM) materials. This study aimed to compare the internal and marginal fit of Ultra translucent multilayered zirconia versus lithium disilicate implant-supported hybrid abutment crowns (HACs) constructed with custom-milled screw-channels on Titanium-base.Materials and methodsA total of 24 HACs with custom-milled screw-channels were constructed from lithium disilicate (Group LDS) and Ultra translucent multilayered zirconia (Group UT) using digital workflow (n = 12). The internal and marginal gaps of HACs on their corresponding Titanium-bases were assessed using replica technique and stereomicroscope, respectively. After testing for normality, quantitative data were expressed as mean and standard deviation and compared using independent t-test at a level of significance (P ≤ 0.05).ResultsThere was no statistically significant difference between Group LDS and Group UT in terms of marginal and internal fit. The internal and marginal gaps in both groups were within the accepted values reported in literature.ConclusionsUT and LDS HACs with custom-milled screw-channels demonstrated comparable and acceptable internal fit and marginal adaptations to Ti-base, which lied within the range reported in literature.

Recent Advances in the Biosynthesis of Mid- and Long-Chain Dicarboxylic Acids Using Terminally Oxidizing Unconventional Yeasts.

As high-performance monomers for the manufacture of polyamide materials, mid- and long-chain dicarboxylic acids (DCAi, i ≥ 6) have received extensive attention from researchers. Biosynthesis is gradually replacing chemical synthesis due to its outstanding advantages in the industrial production of mid- and long-chain dicarboxylic acids, which is mostly achieved by using the strong terminal oxidation ability of nonmodel microorganisms such as Candida tropicalis to oxidize hydrophobic substrates such as alkanes. Here, we first summarize the metabolic pathways of oxidative alkane conversion into dicarboxylic acid by terminally oxidizing unconventional yeasts and the corresponding metabolic engineering strategies. Then, we summarize the research progress on new dicarboxylic acid production processes. Finally, the future development directions in the biosynthesis of mid- and long-chain dicarboxylic acids are prospected from synthetic biology and bioprocess engineering, which can also provide a reference for the synthesis of other biobased chemicals and biomaterials.

Additive Manufacturing of Metal Materials for Construction Engineering: An Overview on Technologies and Applications

Additive Manufacturing of Metal Materials for Construction Engineering: An Overview on Technologies and Applications

Clinical breakage, slippage and acceptability of two commercial ultra-thin polyurethane male condoms compared to a commercial thin latex condom: a randomised, masked, 3 way crossover, multi centre controlled study (SAGCS 2)

BackgroundAlthough natural rubber latex remains dominant as the primary manufacturing material for male condoms synthetic materials first introduced in the early 1990s address many of the limitations of latex including the risk of allergies. Polyurethane elastomers allow condoms to be made significantly thinner to provide greater sensitivity and encourage greater use of condoms for contraception and STI prophylaxis.The primary objective of this Study was to evaluate the breakage, slippage and acceptability of two ultra-thin polyurethane condoms against a thin control latex male condom, designated latex C, in a randomized, cross over, masked, non-inferiority study. The condom designated Polyurethane A was designed for markets where 52/53 mm wide latex condoms are preferred whereas the condom designated Polyurethane B was designed for markets where the smaller 49 mm wide latex condom is preferred.MethodsThe Study was designed to meet the requirements specified in ISO 29943–1: 2017 and FDA guidelines for clinical studies on synthetic condoms. It was conducted by two Essential Access Health centres, one in Northern California and the other in Southern California. Sexually active heterosexual couples (300) aged between 18 and 45 years were recruited to use three sets of five condoms in a block randomized order, recording breakage, slippage and acceptability after each use. A total of 252 couples contributed 2405 evaluable condom uses per protocol for the Condom A versus Latex C comparison (1193 Polyurethane A plus 1212 Latex C), and 247 couples provided 2335 evaluable condom uses per protocol for the Condom B versus Latex C comparison (1142 Polyurethane B plus 1193 Latex C). Only condoms used for vaginal intercourse were included in the analysis.FindingsAlthough the total failure rates (breakage and slippage) for the polyurethane condoms were higher than for the control Latex C condom, all condoms performed extremely well with low failure rates compared to similar condom studies. Condom Polyurethane A met the noninferiority requirements specified in ISO 23409:2011 relative to Latex C, the control NR latex condom, in the full Study population. While condom Polyurethane B did not meet the noninferiority requirement for the full Study population, it did meet the noninferiority requirement when analysis was restricted to the intended population (men with penis lengths ≤ 170 mm).Trial registration The Study is registered with ClinicalTrials.gov, NCT04622306, Protocol Reference SAGCS 2, initial release date 11/02/2020.