Exterior Structure Research Articles

Bacterial Degradation of Low-Density Polyethylene Preferentially Targets the Amorphous Regions of the Polymer.

Low-density polyethylene (LDPE) is among the most abundant synthetic plastics in the world, contributing significantly to the plastic waste accumulation problem. A variety of microorganisms, such as Cupriavidus necator H16, Pseudomonas putida LS46, and Pseudomonas chlororaphis PA2361, can form biofilms on the surface of LDPE polymers and cause damage to the exterior structure. However, the damage is not extensive and complete degradation has not been achieved. The changes in polymer structure were analyzed using Time-domain Nuclear Magnetic Resonance (TD-NMR), High-Temperature Size-Exclusion Chromatography (HT-SEC), Differential Scanning Calorimetry (DSC), and Gas Chromatography with a Flame Ionization Detector (GC-FID). Limited degradation of the LDPE powder was seen in the first 30 days of incubation with the bacteria. Degradation can be seen in the LDPE weight loss percentage, LDPE degradation products in the supernatant, and the decrease in the percentage of amorphous regions (from >47% to 40%). The changes in weight-average molar mass (Mw), number-average molar mass (Mn), and the dispersity ratio (Đ) indicate that the low-molar mass fractions of the LDPE were preferentially degraded. The results here confirmed that LDPE degradation is heavily dependent on the presence of amorphous content and that only the amorphous content was degraded via bacterial enzymatic action.

Architectural approach for evaluation of radiation shielding integration in space habitats

NASA HRP considers developing radiation protection for human space flight and surface habitation as one of the critical technologies for successful deep space exploration. Although the danger of radiation exposure is recognized as a potential show-stopper for deep space exploration, and radiation effects on humans are now understood better than before, shielding strategies for different stages of space flight and habitation are still not addressed in a fully comprehensive manner. Habitats and all space structures planning and design are guided by essential requirements and constraints associated with safety, manufacturing and assembly procedures, propellant and construction costs, maintenance, crew and/or passenger satisfaction. This paper reviews radiation shielding options for space habitats and discusses their feasibility in relation to habitability needs, including the potential for outside viewing in distinct types of space habitats. Typically, radiation protection depends on the thickness of the exterior structure that consists of a pressurized shell, multilayer insulation (MLI) and any applied radiation shielding material. The mass of the external protection shell is the primary factor of radiation shielding effectiveness. Nevertheless, using materials with low atomic numbers (e.g., Boron (5), Carbon (6), and H2O) helps to lower secondary radiation hazards. Water, which is rich in hydrogen and has the lowest atomic number, can also be used for other mission needs. Other materials, including biomaterials, can be considered when their inclusion in the structure is possible and appropriate. The paper presents a comprehensive strategy for radiation shielding selection that includes investigation of complications associated with a type of space habitat structure, mission needs, duration, destination, and crew requirements. The approach presented in the paper aims to establish an evaluation methodology for defining the feasibility of the integration of diverse radiation shielding types into habitat structures. The paper summarizes by reviewing radiation shielding proposals with selected case studies including water, regolith, hydrogen-rich polymers, biotechnology, polyethylene/boron nitride composites, and active strategies.

Design and Analysis of a Vertical Electric Ducted Fan for Unmanned Aerial Vehicles

Several types of multirotor unmanned aerial vehicles (UAVs) are widely used in various industrial activities. UAVs with electric ducted fans (EDFs) have been developed to mitigate the risks associated with rotary blades, which are installed on the exterior structure of conventional UAVs and exposed to the ambient environment. Particularly, vertical EDFs have become a focus in the field of UAV design because they require less space for the flow channel compared with horizontal EDFs. In this study, a vertical EDF UAV model was developed. Structural and flow field analysis was performed in Ansys software to determine the optimal design configuration. The results confirmed that the designed model facilitated smooth air flow with favorable inlet and outlet velocity. The vehicle structure required minor adjustment to reduce the frequency of occurrence of vortices. Overall, this study made two research contributions. First, an EDF UAV model was developed to mitigate the risk of rotary blades being exposed to the ambient environment. Second, a vertical EDF system was proposed to reduce the flow channel space and maintain the outlet velocity, thereby improving the takeoff, landing, and thrust performance of UAVs.

Improving insertions of mutated G20C portal protein into lipid bilayers for nanopore sensing.

In recent years, the third-generation nanopore sequencing technology (nanopore sequencing) has stood out due to its long read lengths, simple operation, portability, and real-time sequence readout, and has also shown good prospects in biomolecular detection. Mainstream nanopore architectures implement transmembrane proteins that insert into an isolative membrane, where the signal resolution of the nanopore is dominated by the nature of the pore protein. Current choices focus on naturally bio-membrane dwelling proteins, whereas a broad range of other proteins may also provide pores suitable for nanopore sensing, although their implementation has been limited by a poor ability to insert into organic membranes. Here, we describe a strategy for inserting viral portal proteins with flexible inner pores into lipid membranes: We expressed different mutants of G20C portal protein to 1) enable chemical modifications of hydrophobic anchors to the portal's exterior structure and 2) substitute hydrophobic amino acid residues into the portal's base in order to facilitate membrane insertion. In this work, we engineered and purified different portal mutants, and verified their structural integrity with electron microscopy. Building on our recent demonstration of DNA sensing with G20C mutants, we are in the process of characterizing the sensing capabilities of these mutants through ionic current recordings of DNA and peptide translocation through the portal mutant. We expect to apply this approach to a wide range of non-membrane, ring-shaped proteins and facilitate the development of new biological nanopores that can provide improved signal resolution and data quality.

Architecture Against Theatre

Architecture Against Theatre

Biomimetic camouflaged nanoparticle-based folfirinox platform for optimizing clinical pancreatic cancer treatment

The most effective treatment of pancreatic cancer (PC) is known as mFOLFIRINOX scheme. However, this regimen has relatively severe toxic effects and are commonly restricted to patients with sound physique, which is poor in drug-selectivity, non-specific causing serious toxicity, greatly limits clinical application. Safer and more effective strategy seamlessly and synchronously is needed as advanced treatments for pancreatic cancer in future. In this report, we exploit a biomimetic nanoparticle-based platform for optimizing mFOLFIRINOX regimen. By coating pancreatic cancer cell membrane (PCCM) onto the surface of polymeric cores that loaded with mFOLFIRINOX, we prepare PCCM-cloaked nanoparticles, namely CNP@folfirinox, which inherit the antigenic exterior structure and associated functions of PC cells. The resulting CNP@folfirinox displays a core-shell nanostructure, which consisting of polymeric core and cancer cell membrane shell with suitable size and surface charge. Particularly, owing to inheriting the inherent membrane protein expressions profile, CNP@folfirinox exhibits prominent advantages in homologous homing to tumor tissue and deep penetration. It also shows lower side effects compared to extensive mFOLFIRINOX i.v. administration with no appreciable toxicity in other organs outside the tumor in vivo. Meanwhile, CNP@folfirinox is endowed with the “Don’t eat me” privilege, hard for the immune system to recognize and less reticuloendothelial system uptake, with prolonged blood circulation, therefore improving delivery efficiency of drug after intravenous administration. Thus, this work reshapes a promising paradigm for more safe and more effective mFOLFIRINOX strategy for further clinical pancreatic cancer treatment.

Fast and deep disinfection for face masks recycle using vacuum ultraviolet irradiation

Nowadays, trillions of used face masks have caused serious environmental pollution, biological risk and energy waste due to improper disposal. It is highly necessary to disinfect and recycle the used masks. In this paper, a sustainable vacuum ultraviolet (VUV) treatment for disinfection of N95 masks was first studied. Typical antibiotic-resistant E. coli were completely inactivated with decreased abundances by 65.82% for 16S rRNA and 76.75% for SHV-4 (an antibiotic-resistance gene) in 5 min, which was further decreased by more than 90% after the prolonged treatment. The mechanism was demonstrated that VUV could damage the exterior structure and interior DNA of E. coli cells due to the synergy of UV, O3 and extensive reactive oxygen species (ROS). The treated N95 masks had no structural damage and functional decline, and were up to the reuse standard. Moreover, a VUV disinfection equipment was fabricated, which can inactivate E. coli cells on the face masks in a few seconds and keep the used masks intact after 20 cycles of disinfection. This study provides a fast, deep and economical disinfection strategy for masks recycling, which can effectively reduce the consumption of fossil energy and plastic pollution to maintain sustainable development.

Outside and inside the time machines: structure and subjectivity in Alain Resnais’s Je t’aime, je t’aime

ABSTRACT This study considers the political significance of Alain Resnais’s Je t’aime, je t’aime through a comparison of the structural determinations imposed on subjectivity by the time machine and the analogous determinations imposed by the mechanism of cinema and the structures of capitalism, demonstrated by the film’s medium and content. To participate in the time travel experiments, Resnais’s character must be both conscious and passive. Like in film spectatorship or life under capitalism, the time-traveling subject is fully aware, but this experience is determined by an exterior structure and its machinations. The exteriorized mechanism of Resnais’s malfunctioning time machine thus permits an outside view of its structural determinations of time that I compare to those imposed by cinema and capitalism, which emerge as time machines of their own. I analyze this using Althusser’s theorization of the conceptual mechanisms that reproduce real objects (time, cinema, capitalism) as thought-concretes. I then suggest, through Rancière’s recent work, that aesthetic experience inside of these time machines presents the potential to recuperate one’s subjectivity from their grasp. To conclude, I contrast Resnais’s character’s solitary experience in the time machine with the collective aesthetic experience of film that is already inclined toward political consequence.

Research and analysis on the dustproof structure of low voltage switchgear

This study improves the dustproof effect by changing the appearance structure of the low voltage switchgear. The exterior structure of the low-voltage switchgear adopts S profile to prevent dust from entering the cabinet body and make dust proof treatment at the connection of the cabinet board parts. Through the dust experiment, compare the protective effect of low-voltage switchgear with common appearance structure, low-voltage switchgear with common appearance structure after dust-proof processing and the new type of structure. Finally, it is concluded that the low-voltage switchgear can effectively reduce the entry of dust by increasing the complexity of dust entry channels, and the S-shaped appearance structure can reduce more than half of the dust entering compared with the ordinary appearance structure.

3D Modeling of Bajang Ratu Temple using UAV Photogrammetry with Oblique Images

The Bajang Ratu Temple is located in Dukuh Kraton, Temon Village, Trowulan District, Mojokerto Regency, East Java, Indonesia, one of the heritage buildings of the Majapahit Kingdom. 3D modeling is one of the efforts that can be used to carry out reconstruction of the Bajang Ratu Temple. In this study, 3D modeling of Bajang Ratu Temple uses a close-range photogrammetry method with low and high oblique images taken using a non-metric camera on the Unmanned Aerial Vehicle. The results of this study were obtained geometric accuracy, that is RMSEx = 0,043 m, RMSEY = 0,049 m, and RMSEZ = 0,092 m for high oblique images. While, for low oblique images, the geometric accuracy are RMSEx = 0,054 m, RMSEY = 0,062 m, and RMSEZ = 0,120 m. The visual analysis results show that the exterior structure of the 3D model formed has resembled the true Bajang Ratu Temple in reality. Based on the shape’s analysis, the 3D model object has an RMSE value of less than 0.5 m, so that it can appropriate the criteria for Level of Detail of order three that is RMSE < 0.5 m.

Intraspecific differentiation by exterior in horses of different breeds

The analysis of the exterior features of horses of the roadster and heavy draft horse breeds by basic and supplementary measurements of body articles and conformation indexes was carried out in order to study the intraspecific differentiation. The results showed significant differences between the racing roadster breeds and heavy draft breeds. The racing roadster breeds were similar in most respects, but the Russian Saddle Horse had more differences compared to other roadster breeds. Soviet Heavy Draft mares were reliably superior to riding mares in most measurements and conformation indices, but inferior to them in terms of neck length. Our research has shown that the selection of highly specialized types of horses leads to a distinct differentiation between breeds of horses in the exterior structure. The resulting digital data should be used for the development of standards and regulations in the breeding of horses for different uses.

Performance of Unidirectional Biocomposite Developed with Piptadeniastrum Africanum Tannin Resin and Urena Lobata Fibers as Reinforcement

The Piptadeniastrum Africanum bark tannin extract was characterized using MALDI TOF, ATR-FT MIR. It was used in the development of a resin with Vachellia nilotica extract as a biohardener. This tannin is consisting of Catechin, Quercetin, Chalcone, Gallocatechin, Epigallocatechin gallate, Epicatechin gallate. The gel time of the resin at natural pH (pH = 5.4) is 660 s and its MOE obtained by thermomechanical analysis is 3909 MPa. The tenacity of Urena lobata fibers were tested, woven into unidirectional mats (UD), and used as reinforcement in the development of biocomposite. The fibers tenacity at 20, 30 and 50 mm lengths are respectively 65.41, 41.04 and 33.86 cN·Tex−1 . The UD biocomposite obtained had very interesting mechanical properties. Its density, tensile MOE, ultimate strength, bending MOE and MOR are respectively 926 kg·m−3 , 6 GPa, 55 MPa, 9.3 GPa and 68.3 MPa. This biocomposite can be used in a building exterior structure.

Structural floor shape efficiency of circular and square high rise structure towards lateral loadings

The building shape is one of the most important considerations in the conceptual stage of building design. Since the building shape determines the size and the orientation of the exterior envelope exposed to the outdoor environment, it can affect building performance in many aspects: energy efficiency, cost and aesthetics. The shape and exterior structure of a house play major roles in determining its energy efficiency and the comfort of residents. The shape is comprised of the building’s height, width, and depth-also known as the footprint. The determination of the structural shape of a high-rise building would preferably involve only the selection and arrangement of the major structural element to resist most efficiently the various combinations of gravity and horizontal loading. Based on the above considerations, this study focuses on the responses by analysing the effects of the lateral loads on two 20 storied high rise structures having edge supported floor systems each of which one with square floor shape and another with circular floor and finally, presents a comparative result.

BTZ gems inside regular Born–Infeld black holes

The regular black hole solution arising as a spherically symmetric vacuum solution of Born–Infeld gravity possesses an asymptotic interior structure which is very well described by a four-dimensional generalization of the non-rotating BTZ metric. According to this picture no singularity exists, and instead, infalling observers experience a constant curvature manifold as they travel towards future null infinity. This is characterized by the BTZ event horizon. The exterior structure of the black hole is also studied, and it is shown that it corresponds to the Schwarzschild solution provided the black hole mass is not too small. In this way, the regular black hole state can be seen as a spacetime which connects two constant curvature asymptotic spaces, namely, the flat Minkowski spacetime in the outside region, and the locally AdS constant negative curvature one characterizing the BTZ-like asymptotic interior.

Bioinspired Hydrogels with Muscle-Like Structure for AIEgen-Guided Selective Self-Healing

Living systems, including human beings, animals, and plants, display the power to self-heal spontaneously after being damaged. The self-healing is usually selective, which means that the healing ef...

Synthesis of a novel nonflammable eugenol-based phosphazene epoxy resin with unique burned intumescent char

Developing bioresourced epoxy resin with excellent flame retardancy is challenging for satisfying environmental and fire hazard requirements. Herein, a novel monomer with six functional epoxy groups was successfully synthesized by combining eugenol with hexachlorocyclotriphosphazene. Using aliphatic diamine as a curing agent, a novel epoxy of EHPE-D230 was prepared, and its properties were systematically evaluated. Compared with commercial epoxy resin (E51-D230), EHEP-D230 possessed a higher tensile strength (56.7 to 64.2 MPa) and better thermal resistance (Tα = 85 to 119 °C). Moreover, EHEP-D230 exhibited a high limiting oxygen index value of 31%, and it passed the UL94 V-0 test without any after-flame time. Cone calorimeter test indicated that the peak value of the heat release rate, total heat release, and total smoke production for EHEP-D230 reduced significantly by 66%, 65%, and 78%, respectively, compared with those of E51-D230. The EHEP-D230 residual char exhibited a compact and continuous exterior structure and a honeycomb-like hollow vesicle interior structure. This unique intumescent char endowed EHEP-D230 with excellent flame retardancy and smoke suppression, rendering it a potential candidate for fire-resistant applications.

Reusability Study of Steel Leaning Column Structure Utilizing Nonlinear Static Analysis

Abstract: Two major earthquakes hit twoplaces in Indonesia in 2018, Palu city with 7.7 SR earthquake, and Lombok island by 6.4 SR earthquake. Many building especially concrete structure building got heavily damaged and even collapsing. Most of the damaged parts are the building’s beam-column joint, due to improper reinforcing. This damaged building is very difficult to repair due to disintegrated concrete. Thus, this building cannot be used anymore, and nothing can bedone except removing the remains and build a new structure. Because of this reason, this paper is studying a concept of reusability in structure, with the purpose to minimize structural damage in certain part of the building using leaner column theory. Leaning columns are columns that are pinned at each connection and provide no bending restraint in system. Theoretically leaning column cannot support axial and lateral loads, but since it is designed to lean on other structure, it can still resist the forces. Hence, this column is not suffering from lateral moment due to earthquake load, and the section is not exposed to damage. This paper is studying behavior of leaning column on exterior part of the structure with numerical simulation. Three-story building is modeled, one is with leaning column system, and the other is without leaning column. Performance-based design analysis with pushover method is carried. Result indicating that by using leaning column, exterior structure is not suffering from high moment when being hit byearthquake, and in other word, the exterior structure is not damaged when the earthquake comes and still can be used again.

A Generalized Transition Matrix Model Combined With Discontinuous Galerkin Method for Open Cavities

A generalized transition matrix (GTM) model combined with discontinuous Galerkin (DG) method is proposed to analyze the scattering problems of open-ended cavities. A virtual reference surface is put to seal the opening of an open cavity and can separate it into an exterior region and an interior region. By mapping the scattering properties of the internal components onto the reference surface, the information interaction of the GTM model occurs on the reference surface only. With its features of nonconformal meshes at the boundary, the DG method makes the model feasible and accurate regardless of the normal continuity of the surface current at the transitional interface. The GTM model is independent of the exterior structure of the cavity and the external fields. The computational cost can be significantly decreased when the GTM model with the identical inner region is reused. Numerical examples demonstrate good precision and efficiency of the presented method.

Application of UAV and Csp1 Matrix for Building Inspection at Muzium Negeri, Seremban

Building inspection is really essential to determine the condition of a building and one of the key components of building maintenance. To determine the defect, visual inspection will be conducted as early phase of building inspection. Usually, binocular and camera will be used as main devices in visual inspection. This research aims to study Museum Negeri defects at exterior structure especially the roof structure by using the Unmanned Aerial Vehicles (UAV) or as known as Drone. The data collected will be analyzed using Condition Survey Protocol 1 Matrix to obtain an overall rating of the building’s condition. The process involved in this study are site visit, planning and preparation before the flight, data collection using UAV, image processing and analyzing data from image. The results of analysis, a total numbers of 53 locations have been identified and documented suffer from defects or faults such as cracking, corrosion and wall perforated. All defects information obtained using UAV visual inspection can help the museum maintenance to do maintenance work. The overall condition of this building structure is 5, where the overall performance of the building is fair.

Tailoring structure of Ni-rich layered cathode enable robust calendar life and ultrahigh rate capability for lithium-ion batteries

Tailoring the structure of Ni-rich ternary layered cathode is considered as an effective way to solve its poor cycling and rate capability. Herein, a special structure of Ni0.6Co0.2Mn0.2(OH)2 precursor, in which strips composed of lamellar primary particles are vertically inserted, is rationally designed through feasible industrialized co-precipitation process. Particularly, precursor possesses a loose interior and dense exterior structure by observation of cross section. After sintering, LiNi0.6Co0.2Mn0.2O2 (NCM622) cathode shows monodispersed microspheres whose external surface is tightly wrapped rod-like primary particles. Moreover, NCM622 microspheres inherits the properties of Ni0.6Co0.2Mn0.2(OH)2 precursor, displaying hollow structure and aligned primary particles along the radial direction. NCM622 cathode shows optimal electrochemical properties in the voltage window of 2.8–4.4 V. It displays a revisable capacity of 142.4 mAh g−1 (79.3% for capacity retention ratio) after 300 cycles under current density of 1 C. A reversible capacity of 110.3 mAh g−1 can be obtained after 500 cycles even at current density of 3 C, and corresponding capacity decay rate is only 0.068% for each cycle. The tailored cathode has great potential applications in batteries of high-power and long calendar life as well as provides an idea for structural design of high nickel cathode.