Polypropylene Containers Research Articles

Detection of Metabolic Gas Emitted by Termites Using Semiconductor Gas Sensors

ABSTRACT The feasibility of using three types of semiconductor gas sensors to detect the metabolic gas generated by termites was investigated. Odor, methane, and hydrogen sensors made of a tin oxide semiconductor were tested. A polypropylene container was prepared with three sensors in the lid to investigate the relationship between the number of termites and food material on gas concentration over time. Worker and soldier termites (Coptotermes formosanus), collected from a laboratory colony, were put into the container with and without food material (wood specimen). The variation in the electrical resistance of the sensors during the detection of gas components was monitored, and the detected voltage was converted into gas concentration. The hydrogen concentration increased with an increase in the number of termites and was not influenced by gases released from the wood specimen. Similar findings were obtained for the odor sensor, even though it detected odor components from both termites and the wood specimen. The methane sensor did not detect any significant increase in gas concentration. The results showed that the hydrogen emission depended on the feeding activity of worker termites, whereas soldier termites that were supplied with food material by worker termites made a small contribution to hydrogen emission. These findings suggest that because of the high selectivity and sensitivity of the hydrogen sensor, its performance is better than that of the odor and methane sensors for the detection of termite attacks.

Improving the Properties of Reinforced Plastics Using the Resin Flow Control Method of Molding - Evaluation of Sealing Performance of Molded Plastic Parts -

We are now engaged in the study of a resin flow control method of molding to positively orient molecules or fillers by displacing resin flows in the mold. This method has proved effective for improving the physical properties of glass fiber reinforced polypropylene molding. This study is aimed at improving the sealing performance of polypropylene containers by circumferentially controlling resin flows in the mold to reduce free volumes. In this paper, we evaluate the sealing performance of such molding in relation to different rotational speeds of the rotational core in the mold.

Preparation Method and Stability of a Temozolomide Suspension: A Pilot Study

ABSTRACTAimTo investigate a compounding process for temozolomide 10 mg/mL suspension from capsules without using a mortar and pestle; and the stability of the suspension under refrigeration (2 to 8 °C) and at room temperature (22 to 23 °C).MethodTemozolomide 10 mg/mL suspension was prepared using a modified formulation and method to contain the product in the final container and limit operator exposure to cytotoxic powder or residue. Decontamination was undertaken of work and finished product surfaces. Samples were stored at room temperature and under refrigeration. Both samples were protected from light and stored in identical polypropylene containers. High‐pressure liquid chromatography was used to assay the potency of the suspension.ResultsThe sample refrigerated and protected from light exhibited little or no chemical degradation for 22 days. At room temperature, the concentration fell below the acceptable concentration after 8 days. An acceptable product was produced which re‐suspended evenly when shaken.ConclusionPreliminary results indicate that temozolomide 10 mg/mL suspension prepared via this method, refrigerated, protected from light and stored in polypropylene containers may be stable for up to 22 days.

Arising of electrostatic charge in the mixing process and its influencing factors

The aim of this work is to improve the understanding of how triboelectric charge arises on pharmaceutical powders and of how it can be influenced and controlled especially with respect to dry powder inhaler development. In the present work the triboelectric properties of mannitol are examined because very few literature treating this new alternative carrier material for dry powder inhalers is available. To study the very complex triboelectric charging process in a simple and controlled way mixing studies are carried out. The powder samples are blended in polypropylene and stainless steel mixing containers for defined durations using a tumble blender (T2F Turbula®, Willy A. Bachofen AG — Maschinenfabrik, Switzerland) and then poured into a Faraday cup where charge measurement is performed. Several influencing factors like mixing time, particle size, mixing container size and the addition of a fines fraction to the powder are studied. In contrast to other published literature the present work focuses on the new alternative carrier material mannitol and uses statistical tools like design of experiments (DOE) to check the significance of the influence of factors and also the interactions between the influencing factors. The study reveals a direct relationship between the arising charge and the container size as well as the fines fraction and an indirect relationship between the arising charge and the particle size. Further also three different charge dissipation scenarios are investigated. It is shown that charge dissipation to the atmosphere is negligible within an hour. Keeping the powder inside the mixing container allowing charge dissipation via the container walls is more effective. Additional grounding of the mixing container does not result in a significant enhancement of the dissipation process. This is because charge transport from the powder bulk to the mixing container walls is limited.

Stability of ready-to-use temsirolimus infusion solution (100 mg/L) in polypropylene containers under different storage conditions

The aim of this study was to determine the stability of ready-to-use temsirolimus infusion solutions under different storage conditions. Solutions were prepared in polypropylene containers by adding temsirolimus injection to 0.9% sodium chloride infusion to reach a final concentration of 100mg/L. The following storage conditions were tested: (i) 4(o)C in the refrigerator; (ii) 20(o)C under room light exposure and light protection; and (iii) outdoor temperature with sunlight exposure. Moreover, stress testing was performed on drug substance at 20(o)C under ultraviolet (UV) radiation (365 nm). A stability-indicating high-performance liquid chromatography (HPLC) method with UV detection was developed for this analysis. Precision was below 4% and accuracy ranged from 97 to 102%. The lower limit of quantitation was 0.1mg/L. The degradation products produced after UV light exposure were detected upon further analysis by mass spectrometry detection. The stability of temsirolimus is light and temperature dependent. After storage at 20(o)C with room light exposure, the rate of degradation was around 0.25%/h; after 1 day, 92.5% of the initial temsirolimus concentration was recovered. When protected from light, at 4 and 20(o)C, losses were decelerated; the decrease in drug concentration was 1.0 and 1.56% per day, respectively. Under daylight exposure, a substantial decrease in drug concentration was observed; after 1h, losses were higher than 10%. Exposed to UV light, half of the drug was lost after 45 min. In conclusion, temsirolimus 100mg/L in infusion polypropylene bags containing 0.9% sodium chloride was chemically stable when protected from light for 4 and 3 days at 4 and 20(o)C, respectively.

Influence of temperature and humidity on the degradation process of ascorbic acid in vitamin C chewable tablets

Ascorbic acid (AA) is the active ingredient of vitamin C chewable tablets. It is unstable even at room temperature, and increased temperature and humidity rapidly increase its degradation. To protect the active substance, we made its coating with polymers ethyl cellulose that provides its thermal protection and protection from moisture. We bet each particle of AA with a layer of polymer by the method of fluidization. Extra protection against thermal effects and penetration of moisture and oxygen provides the packaging. By using four kinds of packaging: polypropylene container for tablets, strips of aluminum and polyvinyl chloride Al/PVC strips, glass bottles, and strips of aluminum and polyethylene (Al.PE/PE.Al) of 3, of 6 months and of 12 months. One of the tablets are stored at room temperature (25 ± 2 °C/60% RH ± 5%), and the rest in terms of accelerated aging or increased temperature and humidity (30 ± 2 °C/65% RH ± 5% and 40 ± 2 °C/75% RH ± 5%). The speed of degradation of unprotected AA usually get doubled when there is increasing of the temperature for every 10 °C. Experimentally the concentration of AA was monitored, its oxidation product-dehydroascorbic acid and its degradation product-diketogulonic acid.

Application of controlled release glass in the production of French marigold (Tagetes patula L.)

This paper investigates the possibility and justification of controlled release glass application as a new ecological material in the production of plants-seedlings of French marigold (Tagetes patula L.). During the investigation its influence on the development of the produced plants-seedlings was monitored. The seedlings were produced in poly-propylene containers (speedling system) and poly-propylene pots (pot system). The trial was conducted in the greenhouse at the Faculty of Agriculture in Belgrade during 2011. In the course of seedling production the glass granulation of < 0.5 mm was added in the following doses: 0, 1, 2, 3, and 4 g/l. The results of the research show a positive effect of controlled release glass application in the production of French marigold seedlings, since high quality seedlings were produced justifying its application. The best effect on the analyzed parameters of plant-seedling development was found when substrate was applied in the dose of 1 g/l.

Dissecting the effect of anions on Hg2+ detection using a FRET based DNA probe

Many biosensors have been developed to detect Hg(2+) using thymine-rich DNA. While sensor response to various cations is often studied to demonstrate selectivity, the effect of anions has been largely overlooked. Anions may compete with DNA for metal binding and thus produce a false negative result. Anions cannot be added alone; the cation part of a salt may cause DNA compaction and other effects, obscuring the role of anions. We find that the sensitivity of a FRET-based Hg(2+) probe is independent of Na(+) concentration. Therefore, by using various sodium salts, any change in sensitivity can be attributed solely to the effect of anions. Halide salts, sulfides, and amines are strong inhibitors; anions containing oxo or hydroxyl groups (e.g. nitrate, sulfate, phosphate, carbonate, acetate, and citrate) do not interfere with Hg(2+) detection even at 100 mM concentration. Mercury hydrolysis and its diffusion into polypropylene containers can also strongly affect the detection results. We conclude that thymine-rich DNA should be useful for Hg(2+) detection in many environmental water samples.

Plastik Sebagai Wadah Garam Beiodium

The utilization of plastic as packaging material in the form of bag has indicated that it was the most economic and practical container, and it has widely used for salt packaging in order to avoid the salt being damaged. The hygroscopics characteristic of the iodized salt could be tolerate by polypropylene and polyetylene plastics container

Increased quality and functionality of kimchi when fermented in Korean earthenware (onggi)

SummaryKimchi was fermented in onggi and other containers at 4 °C for 4 weeks. Two types of onggi were used: glazed and nonglazed onggi. Other containers such as polyethylene plastic containers, polypropylene containers for use in a kimchi refrigerator, stainless steel and glass bottles were used. During the fermentation, kimchi fermented in onggi showed relatively stable acidity change compared with those in the other containers. Also it showed higher lactic acid bacteria multiplication (108–109 cfu g−1 at 4th week) but slower general aerobic bacteria multiplication than the others. The springiness of kimchi fermented in onggi was more than 50% at 4th week, it is higher than the others. Its carbonic acid taste and overall acceptability were excellent in sensory evaluations. The antioxidative and cancer‐cell antiproliferative activities were also greater in kimchi fermented in onggi than the others. Between the two types of onggi, nonglazed onggi showed better results in both properties and functionalities of kimchi. Onggi showed higher gas permeability than polyethylene plastic containers and glass bottles because of its porous structure, and lactic acid bacteria could have benefited from this condition. It possibly contributes to optimal ripening of kimchi resulting in better properties, especially texture and taste, and health functionalities.

HANDLING OF FRESH-CUT PINEAPPLE FOR FRESH CONSUMPTION

Pineapple is one of the popular fruits served in fresh-cut form. At ambient temperature and without protective treatments, cut pineapple turns slimy and deteriorates rapidly, resulting in the development of off flavours and odours within a day. Fresh-cut pineapple sustains substantial tissue injury during processing; the disruption of tissue and cell integrity often increases respiration rate, ethylene synthesis, enzymatic browning and the development of physiological disorders with associated increases in rates of other biochemical reactions responsible for changes in colour (including browning), flavor, texture and nutritional quality (sugar, acid and vitamin contents). The damaged plant tissues also provide a nourishing medium for microbial survival and growth. Chemical treatments with sodium chloride, calcium chloride and ascorbic acid can improve the taste, flesh firmness and overcome the browning problem in cut pineapple of ‘Josapine’. Rigid polypropylene containers are used for the packing system and an oxygen absorbent is inserted in the package for quality enhancement of the stored product. Fresh-cut pineapple can be stored for two weeks at 2°C, one week at 10°C and two days at 25°C. This paper elaborates the handling operations, packing systems and storage requirements for fresh-cut pineapple. Issues involved in maintaining both quality and safety are also discussed.

Efeito do tamanho de tubetes na qualidade de mudas de Jatobá (Hymenaea courbaril L. var. stilbocarpa (Hayne) Lee et Lang.), Ipê-amarelo (Tabebuia chrysotricha (Mart. ex DC.) Sandl.) e Guarucaia (Parapiptadenia rigida (Benth.) Brenan)

A crescente demanda por projetos de restauração florestal, devido aos desmatamentos e à exploração ilegal de madeira, tem exigido pesquisas sobre a produção e a qualidade de mudas florestais. O objetivo deste trabalho foi avaliar a influência de diferentes tamanhos de tubetes na qualidade de mudas de essências nativas de diferentes grupos ecológico-sucessionais. Os tratamentos consistiram da combinação de três espécies: Hymenaea courbaril (jatobá), Tabebuia chrysotricha (ipê-amarelo) e Parapiptadenia rigida (guarucaia); com três tamanhos de tubetes para a semeadura: 50 cm³; 110 cm³ e 300 cm³. O delineamento utilizado foi de blocos aleatórios, com quatro repetições. A qualidade das mudas foi avaliada através dos atributos: altura, diâmetro do colo; área foliar; massa seca da parte aérea e do sistema radicular e índice de qualidade de Dickson. O aumento do volume do tubete gerou ganhos expressivos em altura nas mudas de guarucaia (até 92%) e ganhos menores nas mudas de jatobá (até 14%), o que foi atribuído a maior taxa de crescimento da primeira espécie, característica de início de sucessão ecológica. As mudas de ipê-amarelo apresentaram ganhos consideráveis em biomassa do sistema radicular (51 a 229%) com o aumento do tamanho do tubete. Nas três espécies, o tubete de 300 cm³ proporcionou mudas com altura e diâmetro do colo superiores aos daquelas produzidas nos demais tubetes, possibilitando reduzir o tempo de produção das mudas em até 70 dias.

Shish Formation and Relaxation in Sheared Isotactic Polypropylene Containing Nucleating Particles

The formation and relaxation of shish in molten isotactic polypropylene (iPP) and two samples containing different commercial nucleating particles was studied during and after continuous shear flow. In-situ measurements of the shish were made by simultaneous wide- and small-angle X-ray scattering (rheo-SAXS/WAXS) using synchrotron radiation. In the SAXS patterns, sharp meridional reflections were observed in all three samples during the initial stages of shear flow. Their presence indicates that shish form in discrete steps, by the aggregation of pointlike nuclei into oriented threads. Compared to pure iPP, the addition of both nucleants increased the amount and the dimensions of shish formed. However, the shish also relaxed faster in the presence of both nucleated materials. This behavior was attributed to the particles inducing lower molecular weight chains to participate in shish formation. The particle aspect ratio was observed to greatly influence shish formation. This is explained by modification of...

Methodological remarks on rearing basal Attini ants in the laboratory for biological and evolutionary studies: overview of the genus Mycetophylax

Some studies require fresh biological material for their development. Ant colonies have been reared under laboratory conditions for scientific purposes, and several methodologies for leafcutter ants have been reported in the literature. However, these methods are not well adapted for rearing basal Attini. In this study, we proposed a methodology for rearing basal Attini species in the laboratory based on the evaluation of colonies of the genus Mycetophylax. The complete system consists of two round translucent polypropylene containers inserted one inside the other, where one serves as a chamber proper and the other as a foraging area. Both containers are sealed with their lids, protecting the environment against desiccation. From a total of 29 colonies collected in the field, 22 colonies survived for at least 30 weeks, and Mycetophylax morschi was the most adapted for rearing under laboratory conditions. The main problem with rearing basal Attini in the laboratory is the loss of moisture. Thus, the method applied here may be adopted for rearing other basal Attini, as well as other ant species very sensitive to moisture variation.

Determination of Trace Leaching Phthalate Esters in Water and Urine from Plastic Containers by Solid-Phase Microextraction and Gas Chromatography-Mass Spectrometry

A sensitive method has been developed for determination of trace leaching phthalate esters (PAEs) in water and urine from plastic containers by direct immersion solid-phase microextraction (DI-SPME) coupled to gas chromatography-mass spectrometry (GC-MS). The limits of detection (LODs) for PAEs in water and urine had values between 0.2–8 ng L−1 and 4–70 ng L−1, respectively. The proposed method was successfully used for quantification of trace PAEs in water in microwavable polypropylene containers heated by microwave irradiation and in the urine of patients treated with a glucose injection using polyvinyl chloride tubing.

Improved mini-silo for studying fermentation of silage in laboratory conditions

As an alternative system to glass jars, mini-silo consisting of polypropylene (PP) container for laboratory studies of fermentation dynamics in silage was proposed in our previous study. However, suitability of this mini-silo was questioned, as there was a slight probability of air penetration into container, which would lead to silage deterioration. In this study, an improvement of the original mini-silo system for ensiling was undertaken. A non-transparent PP container was replaced with a see-through container made of co-polymer polypropylene (PP), which had a lid with layer of silicon on its edge, which made this mini-silo practically air-proof. The lid was equipped with a special water valve, for releasing of gas products of the fermentation from the silage. Moreover, the seethrough container made a provision for monitoring of micro-organisms growth and thus better explanation of the obtained results on silage microbiological status. The improved silage system was tested in an experiment in which alfalfa was compacted into transparent containers with addition of two bacterial inoculants. On day 50, percentage of silage surface covered with moulds was visually estimated and samples were taken for determination of total number of moulds and volatile fatty acids. Improved mini-silo system for silage laboratory studies proposed in this paper is simple, economical, practical and capable of preventing air penetration into the silage.

콩나물의 저장 중 품질 변화

풍산나물콩으로 5일간 재배하여 수확한 콩나물을 폴리프로필렌 용기에 물과 함께 담아 <TEX>$4^{\circ}C$</TEX>에서 7일간 저장하는 동안 중량, 견고성, 색도 및 관능적 특성의 변화를 검토하였다. 저장하는 동안 물에 담가 저장한 콩나물의 중량에는 변화가 없었으나 대조군 콩나물은 다소 감소하는 경향을 보였다. 콩나물 머리의 견고성은 감소하는 경향을 보인 반면 줄기의 견고성에는 큰 변화가 없었다. 콩나물의 색도 변화를 분석한 결과, 2일 이상 저장했을 때 콩나물 줄기의 L값은 대조군 콩나물이 물에 담가 저장한 콩나물에 비해 낮았다. 줄기의 b값은 2일 이상 저장 시 수확 직 후에 비해 높았으며 2일 및 4일간 저장했을 때 물에 담가 저장한 콩나물은 대조군에 비해 b값이 낮았다. 물에 담가 저장한 콩나물의 머리와 줄기는 약한 녹색도를 띠었으며 저장하는 동안 녹색도가 다소 증가하는 경향을 보였다. 콩나물의 전체적인 선호도는 저장하는 동안 감소되었다. 4일 이상 저장 시 물에 담가 저장한 콩나물이 대조군 콩나물 보다 전체적인 선호도가 높았으나 7일 저장 시에는 대조군과 물에 담가 저장한 콩나물 모두 매우 낮은 전체적인 선호도를 나타내었다. 따라서 콩나물을 물에 담가 저장할 때는 4일 정도 저장 가능한 것으로 생각된다. Soy sprouts with Pungsannamulkong stored in covered polypropylene container with water(PCSS) or polypropylene film bag without water(PBSS) at <TEX>$4^{\circ}C$</TEX> for 7 days. Changes in weight, instrumental textural hardness, color values and sensory attributes of soy sprouts were evaluated after 2, 4 and 7 day storage. Storage caused slight weight losses in PBSS, but not in PCSS. In the courses of storage the hardness of the heads decreased, while the stems maintained their hardness. The effect of storage periods on surface color changes were also determined. The stems of soy sprouts in PCSS had higher L values when stored for over 2 days. The b values of the stems in both PCSS and PBSS increased after over 2 day storage. The higher b values in the stems were found when kept in PBSS for 2 or 4 days, indicating more yellowish color. On the other hand, the heads and stems of soy sprouts had light green color. The soy sprouts in PCSS became greener with storage, but there was only small increase in greenness. Sensory panels perceived that the overall acceptability of soy sprouts decreased with storage. The overall acceptability of soy sprouts when kept in PCSS for 7 days were not as good as that of soy sprouts in PCSS for 4 days, although soy sprouts in PCSS had a significantly higher overall acceptability than those in PBSS when stored over 4 days(p<0.05). Therefore, PCSS could be possible to keep soy sprouts with good overall acceptability when stored 4 days at <TEX>$4^{\circ}C$</TEX>.

Evaluation of The Relationship Between A Pharmaceutical Compound’s Distribution Coefficient, Log D and Adsorption Loss to Polypropylene in Urine and CSF

The distribution coefficient, D, is a physicochemical property used to determine the partitioning of compounds between aqueous and hydrophobic media at a given pH. A clear relationship was observed between the calculated pH-dependent distribution coefficient of six representative pharmaceutical probe compounds and their propensity to partition between a relatively hydrophobic polypropylene surface and the aqueous matrices, human urine or human cerebrospinal fluid (CSF). Compound log D cut-off values of 1.5 and 3.8 for urine and CSF, respectively, were determined using a threshold of less than 20% adsorption to the polypropylene surface. The ability to forecast the adsorption of a given compound to a polypropylene container with urine and CSF offers an effective means for screening potential issues and identifying when additional testing and corrective measures may need to be applied.

Stability of 11-Nor-delta-9-Tetrahydrocan nabinol-9-carboxylic Acid from Urine Samples Stored in Polypropylene, Polyethylene and Polystyrene Containers at Different Temperatures

The stability of 11-Nor-9-delta-tetrahydrocannabinol-9-carboxylic acid (THCCOOH) from urine specimens stored in polypropylene (PP), polyethylene (PE) and polystyrene (PS) containers was examined. Urinesamples containing 100μg/m L TI-ICCOOH were stored at -20°C, 4°C and 25°C up to 180 days. The samples were analyzed at 0,5, 10, 20, 30, 60, 90, 105, 135, 150 and 180 days, and alteration of the analyte pattern during storage were determined by a validated liquid chromatography-tandem mass (LC-MS/MS). The concentration of THCCOOH significantly decreased to approximately 20% of its initial concentration within 5 days in all three containers at all temperature conditions. All loses of THCCOOH were relatively stabilized after 5 days. The results indicated that THCCOOH was preferred to store in PP and PE containers at 4 °C.

Impact of solar radiation in disinfecting drinking water contaminated withGiardia duodenalisandEntamoeba histolytica/disparat a point-of-use water treatment

To determine the impact of natural sunlight in disinfecting water contaminated with cysts of Giardia duodenalis and Entamoeba histolytica/dispar using plastic containers. Known quantities of Giardia duodenalis and Entamoeba histolytica/dispar cysts in sterile water were exposed to the sun. Containers were made of polyethylene terephthalate, eight painted black on one side, one not painted and another cut open at the top and the last was a high density polypropylene container. Viability testing was performed using vital and fluorescent dyes. The same assays were conducted under cloudy conditions. Thermal control tests were also performed using heat without ultra violet light from the sun. Results show that 99.9% of parasites was inactivated when water temperatures reached 56 degrees C after sunlight exposure. Both solar radiation and heat produced by the sun have a synergistic effect in killing cysts of Giardia duodenalis and Entamoeba histolytica/dispar when temperatures rise above 50 degrees C, with complete death at 56 degrees C, using painted 2-l PET containers. Solar disinfection system using PET containers painted black on one side can be used to disinfect water against Giardia duodenalis and Entamoeba histolytica/dispar using natural sunlight.