Polyvinyl Chloride Sheet Research Articles

A DISTINCTIVE APPROACH TO REHABILITATE PATIENT WITH BILATERAL MAXILLECTOMY DEFECT BY TWO-PIECE HOLLOW OBTURATOR- CASE REPORT

An obturator is a common tool for prosthetic rehabilitation following invasive surgery, particularly in a total maxillectomy case. However, loss of teeth, palatal denture-bearing area, and vestibular retentive undercuts leaves an inadequate anatomic base to construct the definitive prosthesis. This results in compromised retention and stability. The retention problem can be resolved by fabricating an obturator that engages remaining undercuts. But in such acquired large defects, if all undercuts are engaged, the prosthesis may become too heavy, non-retentive, and challenging to insert, particularly in patients with very high and large defects. Therefore, in this case fabrication of two-piece magnet retained hollow obturator was described to make a prosthesis light weight with the use of thermoplastic polyvinyl chloride sheet in first part which provides adequate retention by engaging the desirable undercuts. The second part of the obturator was made hollow by the use of urinary catheter that was removed easily after completion of denture processing. After this, both the parts were attached together with the use of magnets. This technique is economical and easy to use to restore both function and esthetics in patients with bilateral maxillectomy defect.

A disposable homemade screen printed electrode for famotidine analysis using a computer-designed molecularly imprinted polymer based on the MWCNT-Fe3O4 nanocomposite in simulated real samples.

A home-made screen printed electrode (SPE) was designed with a magnetic multi-walled carbon nanotube composite (MWCNT-Fe3O4) and a molecularly imprinted polymer (MIP) for sensitive and selective electrochemical analysis of famotidine (FAM). The SPE was fabricated using non-commercial conductive inks such as carbon and silver inks. The electrodes were printed by a painting technique on polyvinyl chloride (PVC) sheets as a substrate. To optimize the composition of the carbon ink, a mixture design methodology was employed. A computational approach was used to select the functional monomer. The imprinted layer was synthesized by electropolymerization of FAM (template) and pyrrole (PY) (monomer) using cyclic voltammetry (CV) on the working electrode surface modified with the MWCNT-Fe3O4 nanocomposite. Differential pulse voltammetry (DPV) was applied to characterize the template removal and rebinding processes. The Plackett-Burman design (PBD) and central composite design (CCD) investigated the effect of parameters on the MIP/MWCNT-Fe3O4/SPE performance. The sensor exhibited a linear dynamic range of 1-1000 μM (R2 = 0.9919) with a limit of detection (LOD) of 0.027 μM (3sb, n = 3). It demonstrated good repeatability and reproducibility, with relative standard deviations (RSD) of 3.6 and 4.2, respectively. This disposable and cost-effective sensor successfully detected FAM in simulated real samples and correlated well with high-performance liquid chromatography (HPLC) results.

INNOVATIVE METAL COMPLEXES AS PHOTOSTABILIZERS TO IMPROVE THE FUNCTIONAL LONGEVITY OF POLYVINYL CHLORIDE

Polyvinyl chloride (PVC) is involved in diverse applications that significantly influence our daily lives; it is industrially synthesized in various configurations in order to fulfill the target application. However, PVC is susceptible to photodegradation, yielding toxic byproducts detrimental to both the environment and human health, which diminishing its utility lifespan. Addressing this concern, current research explores the application of metal complexes as potential photostabilizers to mitigate PVC photodecomposition. The objective of this study is to investigate the effectiveness of formulated metal complexes in preventing photodegradation. Five metals, namely Cu(II), Ni(II), Cd(II), Zn(II), and Sn(II), are included. Examining parameters, such as molecular weight attenuation, the formation of alkene-laden and carbonyl fragments, and the surface morphology alterations of PVC sheets subjected to irradiation are considered. Findings indicate that these metal complexes exhibit remarkable efficacy in decreasing the photodegradation of PVC, thus presenting a promising avenue for extending its functional longevity. The polymer containing Cd(II) complex unit showed the least damage in the PVC surface due to photoirradiation, followed by other complexes

Contractible Plasmonic Nanospheres Array with Dynamically Tailorable Gap Size for Molecule Trapping and Sensitive SERS Detection

AbstractSurface‐enhanced Raman spectroscopy (SERS) is a powerful analysis technique, and the SERS sensitivity is strongly dependent on metallic nanogaps with a greatly enhanced local electromagnetic field (i.e., hot spots). Once the analytes are located in the hot spot region, their Raman signals are enormously amplified. However, delivering analytes into such tiny hot spots remains a great challenge, particularly for molecules with small Raman scattering cross‐sections and no metal affinity. Here, by employing the isotropic contraction characteristics of polyvinyl chloride (PVC) when heated, a molecule trapping and SERS sensing strategy is demonstrated based on a large‐area ordered gold‐coated polystyrene nanospheres (PS@Au NSs) array with well‐controlled gap size assembled on PVC sheet. Compared with the traditional contraction‐adsorption mode, the developed adsorption‐contraction mode enables efficient delivery of analytes with or without metal affinity into the hot spots between the PS@Au NSs, leading to a significantly improved SERS performance with a large SERS enhancement factor of ≈3.57 × 107. The contractible SERS substrate exhibits a high sensitivity of 10−12 m for rhodamine 6G (R6G), 10−10 m for thiram, and 5 × 10−6 m for 2,3,4‐trichlorobiphenyl, as well as good signal reproducibility with relative standard deviations of 2.81% and 4.25% for R6G and thiram, respectively.

The Effect of an Aluminium Disc Rotator on Polyvinyl Chloride (PVC) Material using 360° Lateral Sliding Disc Triboelectric Generator (TEG)

Triboelectric generatorshave the ability to harvest energy from human activities, mechanical vibration, and other sources to drive minor electronic devices.In many circumstances, charges created from a triboelectric process are referred to as a negative effect or waste energy. Here, this paper will demonstrate an approach of the charging process in friction with a rotator and stator to investigate the effects of rotating speed and the different thickness of electrification to the output voltage. The 360° lateral sliding disc triboelectric generator (TEG) fabricated by connecting an Aluminium disc to the motor as a rotator, while a Polyvinyl Chloride (PVC) sheet placed at the top of an acrylic coated by a copper electrode served as a stator. PVC material with different thicknesses (0.2, 0.5 and 0.7 mm) and grit sizes were used (P500, P1000 and P1500) and prepared prior to the experiment. Thus, three different rotational speeds (500, 1000 and 1500 rpm) were monitored using a tachometer to standardize the speed for each set of experiment. Such as a TEG at 1500 rpm on a 0.2 mm thick sample with P500 grit size modification delivers a maximum voltage output, VRMSof 13.8 mV, with the maximum calculated current of 69 µA and the maximum power density of 0.485 mW/m2.

Dimensional Analysis of the Wear of 3D Printed Dies Used to Form PC and PVC Sheets by Thermoforming

Polymers have been around for a while now, and for the time being they play a fundamental role in our society. As time passes, the number of polymer-based items increases. Thermoforming is a conventional polymer manufacturing process with high potential. This paper explores the surface quality of 3D printing dies after being used in a thermoforming process. A polylactic acid (PLA) die was printed using a Fused Deposition Modelling (FDM) The polymeric blanks formed were Polycarbonate (PC) and Polyvinyl chloride (PVC) sheets of 1.5 mm. The results reveal the effects of the temperature, the thermoforming process time and vacuum time on the wear of the top surface dis not surpass 1mm in the worst zone, and does not affect the polymeric formed sheets.

Methods for virus recovery from environmental surfaces to monitor infectious viral contamination

Accurate quantification of infectious contaminants on environmental surfaces, particularly infectious viruses, is essential for contact transmission risk assessment; however, difficulties in recovering viruses from surfaces using swabs complicates this quantification process. Herein, we identified the factors that significantly affected virus recovery rates and developed an ideal swab method that yielded the highest rate of virus recovery. We comprehensively analyzed the effects of swab type (cotton/polyester), swab water content (wet/dry conditions), surface material, and surface area on the rates of viral RNA and infectious virus recovery.The virus recovery rate was significantly lower than the viral RNA recovery rate (P < 0.01), indicating difficulty in the quantification of infectious viruses. The virus recovery rate was significantly higher under wet conditions than that under dry conditions (P < 0.006), and the virus recovery rate obtained using cotton swabs was significantly higher than that using polyester swabs (P < 0.0001). Furthermore, the virus recovery rate had a strong negative correlation (correlation coefficient >0.8) with the target surface area. The maximum surface area where the virus recovery rate was ≥10% (MSA-10%) was identified as the maximum quantifiable area. For influenza virus recovery, MSA-10% on polyvinyl chloride (PVC) sheet, PVC leather, stainless steel, silicone, glass, and polycarbonate surfaces was 66.7, 193, 60.2, 144, 105, and 15.6 cm2, respectively. For feline calicivirus recovery, MSA-10% on PVC sheet, PVC leather, stainless steel, silicone, glass, and polycarbonate surfaces was 210, 111, 2120, 250, 322, and 180 cm2, respectively.The most accurate and ideal method for quantifying infectious viruses on environmental surfaces with the highest recovery rates meets three specifications: “wet conditions,” “the use of cotton swabs,” and “a target surface area of approximately 10 cm2.

A modular continuous robot constructed by Miura-derived origami tubes

Folding a flat sheet under a specific crease pattern can form a three-dimensional origami tube, which has been proven to exhibit unique mechanical properties and has wide engineering applications. In this study, a novel Miura-derived origami tube is designed, and its precise circular closing condition and mechanical properties are systematically analyzed, revealing that the proposed origami tube has programmable stiffness characteristics. Polyvinyl chloride (PVC) sheet enables the origami tube to have the characteristics of flexibility, bending, compression, and torsion resistance. Then, a modular design strategy for the novel continuous robot constructed with the Miura-derived origami tube as the backbone is proposed. A continuous robot with three origami tube modules in series is designed and fabricated as a representative case. Three steel wires drive each module to achieve independent contraction or bending movement. The unified installation of steel wire-driven motors on the base endows the robot with a lightweight, interconnected inner space, high scalability, and flexibility backbone. The kinematic relationships among the driving space, configuration space, and task space are investigated by geometric model and constant curvature assumption, with the circular trajectory tracking and reachable workspace revealed by numerical simulations. Further, the kinematic decoupling or the multi-driving model based on the stiffness difference of the origami tube between multi-segments is discussed. Finally, three prototype experiments demonstrate both the rationality of introducing origami tubes to design the continuous robot and the application potential.

Sunlight filtered via translucent-colored polyvinyl chloride sheets enhanced the light absorption capacity and growth of Arthrospira platensis cultivated in a pilot-scale raceway pond

In this research, the effects of filtered sunlight traveling through translucent-colored polyvinyl chloride (PVC) sheets on the photoconversion efficiency of Arthrospira platensis are investigated. Filtered sunlight improves the phycobilisome’s capacity to completely absorb and transport it to intracellular photosystems. Findings indicated that filtered sunlight via orange-colored PVC sheet increased biomass dry weight by 21% (2.80 g/L), while under blue-colored PVC sheet decreased by 32% (1.49 g/L), when compared with translucent-colored (control) PVC sheet (2.19 g/L) after 120 h of culture. The meteorological conditions during the 1st week of cultivation reported higher light flux than the subsequent weeks. Furthermore, sunlight filtered through orange PVC sheet enhanced protein, allophycocyanin, phycocyanin, chlorophyll-a and carotenoids synthesis by 13%, 15%, 13%, 22%, and 27%, respectively. This practical and inexpensive solar radiation filtration system supports large-scale production of tailored bioactive compounds from microalgae with high growth rate.

Bis(2-ethylhexyl) phthalate transfer from polyvinyl chloride sheet to several kinds of particles

Bis(2-ethylhexyl) phthalate (DEHP) transfer from a polyvinyl chloride (PVC) sheet to 9 kinds of particles, namely, polyethylene particles (1–10, 45–53, 90–106 μm), soda lime glass particles (1–38, 45–53, 90–106 μm), black forest soil, carbon black, and cotton linter, for the particle weights of 0.3, 1, 3, and 12 mg/cm2, were determined for 1, 3, 7, and 14 days using a passive flux sampler (PFS), as well as standard dust. Transfer amounts to small polyethylene particles (1–10 μm), black forest soil, and carbon black were large (8.5, 16, and 48 μg/mg-particle, respectively, for 0.3 mg/cm2 for 14 days) and were similar to standard house dust (35 μg/mg-particle). On the other hand, transfer amount to large polyethylene particles (0.056–0.12 μg/mg-particle), soda lime glass (0.18–0.31 μg/mg-particle), and cotton linter (0.42–0.78 μg/mg-particle) were much lower. The DEHP transfer amount to the particles was proportional to the surface area of the particles, but not associated with the organic content. The DEHP transfer amount per surface area to small polyethylene particles was larger than that of other particles, suggesting the contribution of absorption into the polyethylene particle. However, for the larger polyethylene particles with different manufacturing process that may have different crystallinity, the contribution of absorption was small. The amount of DEHP transferred to soda lime glass did not differ from 1 to 14 days, suggesting that an adsorption equilibrium was reached after 1 day. The estimated value of particle/gas partition coefficients of DEHP, Kpg, of small polyethylene, black forest soil and carbon black were much higher (3.6, 7.1, and 18 m3/mg, respectively) than those of large polyethylene and soda lime glass particles (0.028–0.11 m3/mg).

Releases of micropollutants from building surface materials into rainwater and snowmelt induced runoff

Building surface materials, exposed to wash-off by rainwater or snowmelt, are recognised as one of the significant urban diffuse pollution sources contributing to the impairment of stormwater quality. The pollution conveyed by roof runoff originates from two potential sources, migration of surface material constituents, or wash-off of pollutants deposited on the surface by atmospheric deposition. This study investigated the releases of metals and several groups of contaminants of emerging concern: alkylphenols, alkylphenol ethoxylates, and phthalates, from commercially available materials, which are commonly used on buildings and structure surfaces in the urban environment. The materials tested included the following: metal sheets of stainless steel, copper, zinc, galvanised steel, corten steel, corrugated and coated steel, coated zinc; and bitumen-based roofing felt and shingles, as well as polyvinyl chloride (PVC) from two manufacturers. The stainless steel was considered a control material serving to estimate pollutant contributions deposited on the pilot panels from the surrounding environment. Moreover, this study presents novel data on roof snowmelt induced runoff quality, not reported in the previous literature. The experimental setup consisted of 2-m2 rectangular panels mounted in triplicates of each material and placed in an open-air setting on the campus of Luleå University of Technology, Sweden. Runoff leaving the gently sloping material panels was collected during 11 rain and three snowmelt driven runoff events occurring over a five-year period. The results showed that, in general, the micropollutant concentrations and loads were lower in snowmelt than rain induced runoff, and no decreasing trend was detected in the releases of phthalates or metals during the study period. Moreover, on a yearly basis, copper sheets were estimated to release 0.6 g/m2 Cu to runoff, zinc and galvanised sheets 1.3 and 0.7 g/m2 Zn, respectively, and, PVC sheets were estimated to release up to 78 mg/m2 of diisononyl phthalate (DINP).

Application of Polyvinyl chloride sheet as delayed surgical obturator in maxillectomy defects secondary to mucormycosis- A case series.

It was a great challenge for the prosthodontist to rehabilitate and sustain the prosthesis in patients with bilateral maxillectomy defects due to mucormycosis seen with Covid-19 during second wave in India. In such extensive defects there was difficulty in retaining the obturator due to the absence of soft tissue or anatomical undercuts, condition of existing dentition, retained inferior turbinates and limitation in taking retention from defect side during healing phase. In such extensive maxillectomy defects, retention, stability and support can be enhanced by maximum preservation of hard and soft tissues, skin grafting and removal of inferior turbinates to provide a larger surface area for stress distribution. But here, in this case series, maxillectomy defects with retained inferior turbinates presented a problem in retaining the obturator prosthesis due to limitation in taking retention from the defect side. The conventional method of fabrication of obturator using autopolymerizing acrylic failed in terms of weight of the prosthesis and in gaining retention from the defect side during healing phase. Therefore, thermoplastic vacuum pressed Polyvinyl chloride sheet (PVC) was used for fabrication of delayed surgical obturator due to many merits conferred by it. Its light weight, non porous nature, easy adaptability, patient comfort, efficient undercut engagement, hygienic nature makes it a good treatment option. The main cocern was to close oro-nasal communication to eliminate the need of nasogastric tube and to prevent nasal regurgitation. In all cases, patients were comfortable with the obturator prosthesis in terms of adaptation and function.

Mechanical Characterization and Feasibility Analysis of Polymer Fiber Composite Material

Abstract: The most prevalent reinforcing component in composite materials is carbon fiber. However, obtaining the monofilament's performance metrics of carbon fiber is a challenging task. In this study, we have used PolyVinyl Chloride (PVC) sheets having low mechanical properties. Our goal is to improve the mechanical properties of PVC sheets with the wrapping of carbon fiber. The wrapping of carbon fiber is done by the Hand Lay up method. In this paper, we analyze and compare the mechanical properties of the sheet by using two, four and six layers of carbon fiber on PVC sheets . The main aim of this study is to enhance the mechanical properties of PVC sheets by increasing the number of layers of carbon fiber without replacing the sheet and without enhancing the overall cost.

Mechanically controlled robotic gripper with bistability for fast and adaptive grasping

This paper presents a novel bistable gripper inspired by the closure motion found in the jaw of a hummingbird. With a bistable characteristic, the robotic gripper can grasp objects rapidly without applying continuous external force. The bistable gripper comprises a linkage-driven mechanism and two bionic jaws consisting of thin elastic polyvinyl chloride sheets with two clamped ends connected by a hinge. The shape of the thin sheets was modeled and optimized using geometric analysis, and the morphing processes of the bionic jaw were analyzed using finite element simulations and experiments. Furthermore, we explored the motion characteristics of the clamps during the snap-through and snap-back processes and divided the motion into two phases: delay and snap. Force and response time tests show that the proposed bistable gripper can achieve fast bending within milliseconds under a low pull force during the snap phase. Grasping experiments demonstrated that the proposed robotic gripper is adaptable for grasping objects of various shapes and weights. After grasping, the bistable gripper can release the target by pulling the actuating rod and automatically return to the open state. This study reveals the unique bending mechanism of thin sheets that can be exploited for fast, versatile, and adaptive grasping. The bistable gripper exhibits the potential to reduce energy consumption and simplify control when performing tasks in unstructured environments such as space and underwater.

Preparation and performance of PVC long‐term heat stabilizer based on the synergistic effect of uracil and metal complexes

AbstractIn order to improve the deficiency of traditional polyvinyl chloride (PVC) heat stabilizer, triazole‐based zinc‐containing complex (abbreviated as [Zn(ttr)(OAc)]) with good compatibility with PVC and a strong ability to absorb HCl was prepared in this paper, which was characterized by Fourier transform infrared (FTIR) spectroscopy, scanning electron microscope (SEM) and thermogravimetric analysis (TGA). PVC sheets were prepared by mixing PVC with composite heat stabilizer (DAJ) composed of [Zn(ttr)(OAc)] and 1,3‐dimethyl‐6‐aminouracil (DAU). Different kinds and amounts of common auxiliary heat stabilizers were selected and added to the DAJ system to study the effect of thermally stable system on PVC by Congo red test, Discoloration test, Dynamic thermal stability test, SEM, TGA and Transmittance test and the relevant mechanism was explored. The PVC sheets with DAJ blended by 1.2 phr DAU and 0.8 phr [Zn(ttr)(OAc)] showed relatively excellent coloring properties, long‐term thermal stability, and high light transmittance. Compared with dibenzoylmethane (DBM), 0.5 phr sorbitol and 1.5 phr epoxy soybean oil (ESBO)/Antioxidant 168 showed good synergistic effect with DAJ. Due to the polyhydroxy nature of sorbitol, the thermal stability of PVC was significantly improved, and the transmittance of PVC benefited from the similar miscibility of ESBO long chain. This was also confirmed by TGA and SEM of PVC sheet.

Study on torsion of PVC part formed by incremental sheet forming

The development of plastic product prototype by incremental sheet forming (ISF) has attracted extensive attention. Forming polyvinyl chloride (PVC) sheet into parts by ISF has a wide application prospect in many industrial fields. However, torsion is a problem that needs to be solved. In this paper, some truncated pyramids were formed by different feed speeds and tool paths with a certain spindle speed of the tool. Torsion angle of central line and accuracy of each formed part were measured. In addition, numerical simulation was also used to get the influence of tool path on the torsion of PVC parts. The results show that PVC part appears torsion around the central axis when it was formed by the unidirectional direction tool path, and torsion increases and accuracy reduces with increment of feed speed of the tool. Otherwise, the alternating bidirectional direction tool path can effectively eliminate the torsion of PVC part.

Evaluation of shields and ventilation as a countermeasure to protect bus drivers from infection

We evaluated the deposition of droplets and droplet nuclei—generated by simulated coughing and talking from three points in a bus—on the driver's face and on surfaces around the driver (e.g., the steering wheel), based on whether countermeasures were taken, and assuming that an infected passenger was talking to the driver. When a shield, such as acrylic boards or polyvinyl chloride (PVC) sheets, was used as the countermeasure, the deposition of artificial droplets (>4 μm), emitted from beside or behind the driver, on his eyes, mouth, and cheeks reduced by two to three orders of magnitude or more. Deposition on the surfaces around the driver was also reduced following the use of shields. For artificial droplet nuclei (1.3 μm of polystyrene latex (PSL)) emitted from atomizers beside the driver, the operation of the ventilation fan (VF) and air conditioner (AC), and defroster (DEF) greatly reduced the driver's exposure, while the use of the shield did not. The infection risk of the driver was estimated through exposure to the virus via transfer to the mucosa via hands or surface-to-finger, direct adhesion on the mucosa, and direct inhalation of droplets and droplet nuclei. This is under the assumption that the droplets and droplet nuclei measured in this study are 40% the diameter of those after immediately leaving the mouth of the infected person and are constant regardless of particle size. When using the shield, total infection risk via droplet, airborne, and contact transmission was decreased by 75.0–99.8%. When the shield was not installed, the infection risk decreased by 9.74–48.7% with the operation of the VF, AC, and/or DEF.

Dechlorination of Polyvinyl Chloride via Solvothermal Treatment with Glycerol

Solvothermal treatment using glycerol effectively removes chlorine from polyvinyl chloride (PVC). Additive-free PVC was dechlorinated by treatment with glycerol in an autoclave at 200–240 °C. Liquid glycerol was coexistent with a red powder after the reaction at 200 °C. At reaction temperatures of 220 and 240 °C, the liquid glycerol disappeared, and carbonization proceeded to form a black powder. In this reaction, the glycerol was directly converted into glycidol. Epichlorohydrin was also produced from the glycerol via 1,3-dichloro-2-propanol as an intermediate. The PVC was converted into the polyethylene oxide structure, following the generation of the polyene structure by zip-elimination. Finally, the converted PVC was resinified by an epoxidation reaction with the glycidol and epichlorohydrin. Thus, glycerol acted as a useful reaction medium for this reaction system. The analysis of the decomposition ratio and dechlorination yield showed that the PVC was converted into solid products in high yields via chlorine release, and 30% of the glycerol was solidified by resinification at 240 °C. The effects of the additives on dechlorination were investigated using commercially available PVC sheets. Elemental analysis showed that the calorific value of the solid product dechlorinated at 240 °C was found to be higher than that of standard bituminous coal.

Construction of a Modified Clip Cage and Its Effects on the Life-History Parameters of Sitobion avenae (Fabricius) and Defense Responses of Triticum aestivum.

Simple SummaryClip cages are increasingly used in the study of plant–small insect interactions; however, the heavy weight and low light transmittance of clip cages cause damage to plants and affect insect growth and reproduction. This study aimed to develop a lightweight, transparent clip cage and investigate its effects on Sitobion avenae (Fabricius) and Triticum aestivum. The results indicate that the modified clip cages neither altered the S. avenae life-history parameters nor activated the T. aestivum defense responses and can, therefore, be used for plant–aphid interaction studies.Clip cages are commonly used to confine aphids or other small insects to a single leaf when conducting plant–small insect interaction studies; however, clip cages are usually heavy or do not efficiently transmit light, which has an impact on leaf physiology, limiting their application. Here, simple, lightweight, and transparent modified clip cages were constructed using punched clear plastic cups, cut transparent polyvinyl chloride sheets, nylon organdy mesh, and bent duck-bill clips. These cages can be clipped directly onto dicot leaves or attached to monocot leaves with bamboo skewers and elastic bands. The weight, production time, and aphid escape rates of the modified clip cages were 3.895 ± 0.004 g, less than 3 min, and 2.154 ± 0.323%, respectively. The effects of the modified clip cage on the growth, development, and reproduction of the English grain aphid (Sitobion avenae Fabricius) in comparison with the whole cage were studied. The biochemical responses of wheat (Triticum aestivum) to the cages were also investigated. No significant differences were observed in the life table parameters, nymph mortality, and adult fecundity in S. avenae confined to clip cages and whole cages, but the clip cages were more time efficient than whole cages when conducting life table studies. Moreover, the hydrogen peroxide accumulation, callose deposition, and cell necrosis in wheat leaves covered by empty clip cages and empty whole cages were similar, and significantly lower than treatments where the aphids were inside the clip cage. The results demonstrate that the modified clip cages had negligible effects on the plant and aphid physiology, suggesting that they are effective for studying plant–small insect interactions.

The Facile Strategy of Improving the Long-Term Stability of Highly Transparent Polyvinyl Chloride by Introducing Unsaturated Zn Oleate and Uracil Derivatives.

In order to improve the initial color and the long-term heat stability of super-transparent polyvinyl chloride (PVC), a series of composite heat stabilizers consisting of unsaturated Zn oleate and uracil derivatives have been designed in this paper. The uracil derivatives are 1,3-dimethyl-6-amino-uracil (DAU) and 6,6′-diamino-1,1′,3,3′-tetramethyl-5,5′-(ethylidene)bisuracil (OSU). The static thermal stability, dynamic thermal stability, and transparency were used to evaluate the properties of the stabilized transparent PVC sheets. The results indicate that the compatibility between the stabilizer and PVC was greatly enhanced by introducing an unsaturated long-chain Zn oleate and a long alkyl chain bisuracil derivative. Through the thermal discoloration test, the best ratio of DAU/zinc oleate (DAU/Zn) and OSU/zinc oleate (OSU/Zn) was determined to be 4:1, with a total amount of 3 phr in 100 phr PVC. It was verified that the combination of zinc oleate with uracil derivatives could improve the long-term thermal stability of PVC, and the DAU/Zn was better than that of the OSU/Zn. In addition, through the transmission/haze verification, adding a proper amount of epoxidized soybean oil (ESBO) and phosphite ester to the OSU/Zn system has a certain synergistic effect. The thermal stability and transparency of PVC can be remarkably enhanced.