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  Alquila la mejor furgoneta.
Enviado por: unamigocerrajero - 5 horas - Foro: Tarot en Albacete - videntes buenas de Albacete y tarotistas - Sin respuestas

Un gusto en saludarles.

El internet nos ha permitido muchas posibilidades, ya que gracias a esto podemos tener a mano cualquier tipo de información que nos puede ser útil en muchas ramas de la vida cotidiana, como, por ejemplo, desde un aspecto laboral, como una forma de gozar de algún tipo de entretenimiento, académicamente es esencial ya que tenemos a la mano la facilidad de empaparnos de alguna información o tema que necesitemos, entre otras cosas. Así pues, muchas de estas opciones son posible gracias a distintos sitios como el de alquiler furgonetas valencia que son actualizados cada cierto tiempo con la mejor tecnología en cuanto a modelos, colores y estilos de furgonetas.

Fue un placer.

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  Cuidarnos en la red
Enviado por: alfre123do - Ayer, 09:30 PM - Foro: Tarot - Sin respuestas

Que tal amigo del foro, espero estén bien todos ustedes. Sin duda alguna cuando estamos navegando en el internet, siempre debemos tener en cuenta sobre las páginas que visitamos, ya que hay muchos sitios que no son muy seguros, y debemos evitar al 100% dar información sobre nuestros datos personales, para evitar cosas grabes a futuro. Hace unas semanas me dispuse a eliminar contenido de Google donde aparezco, ya que por error subí datos muy personales, que me pudo haber traído consecuencias. A la final de todo lo hice a tiempo, antes de que otras personas lo vieran, y se regara por la red. Es hay donde debemos cuidar de lo que subimos al internet. Sin más que decir cuídense.

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  Mejora en el padel.
Enviado por: unamigocerrajero - Ayer, 09:21 PM - Foro: Tarot en Albacete - videntes buenas de Albacete y tarotistas - Sin respuestas

Saludos Cordiales,

Dedicar su tiempo y esfuerzo al padel dará sus frutos. Sin embargo, el compromiso en el campo debe reflejarse en las tareas escolares y en la vida. Recuerda que todo lo que vale la pena requiere esfuerzo y nada es gratis. Tampoco debes preocuparte por el costo de las cosas, ya que puedes encontrar en la web overgrips padel accesibles y de calidad.

Hasta luego.

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  Personal y arquitectonico
Enviado por: unamigocerrajero - Ayer, 05:17 PM - Foro: Tarot en Albacete - videntes buenas de Albacete y tarotistas - Sin respuestas

Un saludo especial.

La decoración de algún espacio en particular"," sea tu hogar, oficina o el lugar que desees, es muy importante ya que de esta manera le damos un toque personal que nos hace sentir mayor empatía con estos sitios. Así pues, una de las mejores maneras para lograr que un sitio lleve nuestro toque personal son aplicando las reformas. En ayuda pfc arquitectura nos ofrecen la mejor y mas personalizada atencion en cuanto a reformas. Además, en esta página encontramos ingeniosas imágenes e ideas que nos pueden ayudar a tener una mejor vision de las determinadas reformas que deseamos realizar en nuestro espacio.

Hasta luego.

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Corazón Tarot Del Amor
Enviado por: Taroteca - 19-09-2021, 12:13 AM - Foro: Tarot Madrid - videntes buenas en Madrid - Sin respuestas

[Imagen: bello-21.jpg] [Imagen: 43914.jpg]

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Corazón Tarot Sentimental
Enviado por: Taroteca - 19-09-2021, 12:11 AM - Foro: Tarot - Sin respuestas

[Imagen: bello-20.jpg]


[Imagen: sensua10.jpg]

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  Colgantes para el estilo
Enviado por: alfre123do - 18-09-2021, 03:58 PM - Foro: Tarot - Sin respuestas

Saludos amigos del foro, espero estén bien todos ustedes. Una de las cosas que me gusta comprar siempre son colgantes, para verme bien. Me gustan mucho los colgantes de P D Paola, ya que cuenta con muy bonitos diseños, además que son artesanales, y brindan lo mejor, para que nos veamos muy bien. Si por alguna razón deseas saber más, te comparto la web de franciscoortuno.es, para que veas lo que tiene, para ofrecer.

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  How Do Air Compressors Work?
Enviado por: E234B - 18-09-2021, 02:48 AM - Foro: Reglas del Foro - Sin respuestas

How Do Air Compressors Work?

How Do Air Compressors Work?


Air compressors are an invaluable tool for both industrial work and DIY at home, and there are several different types to choose from depending on the job you need doing. Air compressors have a number of uses, such as to fill gas cylinders for industrial purposes and scuba diving, to create the power needed to run pneumatic tools and spray guns, for pumping up automotive tyres, and within heating and air conditioning systems.






As we’ve touched on here, there are myriad uses for screw air compressor both in commercial and domestic environments. Within the category of air guns, there are several types, each of which is suitable for a different job. We’ve compiled a guide to all the major types of air compressor, how they work and how they differentiate from one another.






Whether you’re an engineering manager or in charge of facilities for your company, being informed about how air compressors function and what they’re used for is handy and can help you make the proper decisions for your business and industry.






Get all the information you need to know about air compressors, complete with the infographic below, with our comprehensive guide. We’ll address the benefits of using premium air compressors in your industry, as well as the questions of ‘what are compressors?’ and ‘how does a compressor work?’, covering all the essentials in one convenient place.






The infographic below shows how a Hydrovane series rotary sliding vane air compressor works






Since their invention in the 19th Century, mechanical, automated air compressors have continued to be one of the most widely used tools in industrial settings. Air compressors provide a continuous stream of power that is safer and cooler than many other forms of energy. For many industries, such as metal work and mining environments, air compressors are an absolutely essential tool. After the basic utilities of water, gas and electric, compressed air is actually considered to be the fourth utility.






Air compressors are also an affordable choice of tool for many manufacturing jobs, as they are durable, and high quality types require minimal maintenance and repairs.






Between the two main categories of compressor – the scroll (piston) compressor and the rotary screw (reciprocating) compressor, you have a tool for every type of industrial and commercial setting, as well as various domestic uses.






The most common types of regular screw air compressor are single and dual phase, both of which operate in the same fundamental way, only dual phase has one more step involved in the compression process. In a single phase compressor, there is one chamber and the air is compressed a single time; in a dual phase, there are two chambers and the air is put through compression twice.






Be careful not to confuse single and dual phase compressors with the number of cylinders a compressor has. Both types of compressor use two cylinders; one-cylinder compressors are less common, because air balancing is made easier with two cylinders. The difference between single and dual stage compressors is that in the former the cylinders are both the same size; in the latter they are different sizes.






How Do Single and Dual Phase Compressors Operate?


Single phase compressors, also referred to as piston air compressors, works in a relatively simple and straightforward way. First, air is drawn into the cylinder; from here, it is compressed once by a single piston movement within a vacuum system.






The power of this compression is measured in PSI (pounds per square inch) or Bar – the higher the PSI/Bar, the more power the compressor has. In a single stage air compressor, the air is typically compressed at a rate of around 120 PSI (8.2 Bar). After the air has been compressed, it is sent into the storage tank from where it is dispelled into various tools as a source of energy.






Dual phase compressors operate the same way, except there are two stages of compression, rather than just one. After the first round of compression, the air is sent into a second chamber, where it is compressed for the second time, at a rate of around 175 PSI (12.1 Bar). After this, the air is sent to a storage tank in which it is cooled down and ready for application.






Both types of compressor are typically powered by either an electric or petrol motor, which drives the piston and causes the compression to happen.






Single Phase and Dual Phase Applications


Both function in fundamentally the same way and can be used for similar tasks, such as operating a pneumatic drill or other high-powered tools such as those found in a manufacturing plant.






Single phase compressors tend to be used within domestic settings for smaller workshop jobs done with handheld tools, such as woodwork, metal work and general DIY.






Dual phase compressors, on the other hand, are better for larger scale work in operations such as operations needed in vehicle repair shops, pressing factories and other plants where parts are manufactured.






Oil-Free vs. Oil-lubricated Air Compressors


Another way to compare variable frequency air compressor is to look at whether they use oil or not – there are oil-free and oil-based / lubricated compressors and both are suited to slightly different jobs. For the air to be drawn into the chamber safely and effectively, the piston needs to be in top working order. To work properly, the piston must be lubricated with oil.






With regards to lubrication, there are two main types of compressor to choose from: oil-free and oil-based. The oil is used on the cylinder to ensure the compression goes smoothly.






The Difference Between Oil-Free and Oil-Based Compressors


Oil-free air compressors already have a lubricated cylinder (often with a non-stick material such as Teflon) and therefore require no further maintenance to work properly. Oil-based compressors require oil to be added to the piston area and changed regularly. Just how often you need to change the oil will be outlined in the manufacturer’s manual that came with your compressor.






On the whole, oil-free compressors tend to weigh a lot less than oil-based compressors, as not only do they not have the weight of the oil, but they are more compact machines, requiring fewer separate parts to make them work. Oil-free compressors, being less complex in design, also tend to be more affordable than oil-based compressors.






However, although they’re more weighty and expensive, oil-based compressors have their benefits. For one thing, they are strong and durable, and usually have a longer lifespan than their oil-free counterparts. This is usually because over time the greasing material (usually Teflon) begins to wear down and lose its lubrication abilities.






Another important factor that should be considered when choosing between an oil-free and oil-based compressor is that the oil-less version tends to heat up faster and to a higher temperature than those which use oil. Compressors without oil also make a lot more noise than those with, so if you want a less noisy workplace, this is a factor to consider too.






Oil-Free and Oil-based Compressor Applications


Oil-free compressors are a great option for those in need of a lightweight, low maintenance tool for home use. Oil-based compressors are better suited to heavy duty jobs and commercial and industrial use, as although they’re generally heavier and require more maintenance, they are also more robust and versatile.






For industrial purposes and extensive, day-long use, oil-based compressors are by far the best option. If you’re looking to invest in quality compressors for your business, opting for oil-based machines is almost certainly the best route to take.






Within an industrial or commercial setting, there are numerous uses for oil-based PM screw air compressor, including:






Vehicle painting and repairs


Sanding and woodwork


Creating snow banks in ski centres


Tools within dentistry and other medical environments


Pneumatic construction tools such as nail guns


Air cleaning tools such as blowguns


Oil-free compressors can be used for domestic use, such as small-scale jobs like blowing up balloons, home workshop and DIY jobs. They are also largely used in industries where there is a need to avoid the product or consumer coming into contact with oil: food and beverage, pharmaceutical and dental, for example. In these sensitive applications, the consequences of having oil contamination in the air are too high to risk, so having an oil free compressor is a must. There is compressed air quality testing from the International Organisation for Standardisation (ISO) which oil-free technology can help you achieve.






Fixed vs. Variable Air Compressors


Another factor to consider when choosing the right type of air compressor for your industry is whether they’re equipped with fixed or variable speed. Let’s take a closer look at what these different types of compressor can do for you.






The main difference between air compressors that use a fixed speed system and those that use variable speed is the manner in which the motor gets its power. The compression element is much the same across all machines, but the way the motor operates has an effect on the usability, efficiency and lifespan of the machine.






How Do VSD Compressors Work?


Variable speed compressors (often referred to as VSD (Variable Speed Drive) or VFD (Variable Frequency Drive) – compressors) operates by automatically adjusting the motor speed in accordance with the demand for air. This happens through a system that converts voltage from the mains power supply into a variable frequency.






Power is drawn through a converter, inside which it is converted twice. First, it converts AC power into DC power using diodes. A capacitor then cleans the AC, and then converts it to DC using a transistor, which acts as switches. These switches control the frequency of power sent to the motor, which in turn controls the speed of the motor.






A VSD air compressor contains this technology, allowing the speed of the motor and the amount of air compression used to be closely controlled. There are pros and cons to both variable speed compressors and their counterpart, fixed speed compressors – check them out below to decide which one is best for your industry.






Fixed Speed Pros and Cons


Fixed speed air compressors send a consistent, continuous stream of power into the motor, which gives you a reliable frequency in all your air compression jobs. The initial cost of fixed speed compressors is lower than that of variable speed compressors, is easier and cheaper to maintain and is a must-have within industries where the power demand is continuous.






This type of compressor is, however, less efficient than its variable speed counterpart. It is also less efficient at saving energy, and can therefore be more expensive to run, with fewer incentives available too.






Variable Speed Pros and Cons


Variable speed air compressors allow you to control the voltage and the frequency of the power in the motor, giving the user more agency over the tool. This type of compressor is more efficient when it comes to power usage, as you can easily control your output and only use what you need. Many industries will find that this type of air compressor is ideal, as it can be used in line with the demand of the job. When less power is needed, you can easily adjust the speed of the compressor, saving money and protecting the environment at the same time.






The downsides of a variable speed compressor are that there is a higher initial capital cost to pay, and maintenance and repairs are more expensive too. They are also not well suited to applications that require a continuous stream of power.






Piston Compressors, Scroll Compressors & Rotary Screw Compressors


So far in this article, all the compressors mentioned are operated using pistons, which is a generic system for one type of compressor – the scroll compressor, also known as a reciprocating air compressor. The other type is the rotary screw compressor, which doesn’t have pistons and operates in a slightly different way.






 






Here’s a quick overview of how scroll compressors and rotary screw / reciprocating compressors work, and what the unique benefits are of each of them.






Scroll Compressors


Scroll compressors are a type of piston compressor, and are also called reciprocating compressors. These are the most common type of two stage air compressor, due to affordability and general availability. But how does a reciprocating air compressor work? The piston system works by having a piston travel downwards, decreasing the pressure inside its internal cylinder through the creation of a vacuum. The sudden change in pressure causes the door of the cylinder to be forced open, and draw air in. When the piston travels up again, the air is forced out of the cylinder at a much higher pressure point. This continues in a reciprocating, ‘scroll’ pattern, hence its name.






Pros and Cons of Scroll Compressors


Pros:






Cools down quickly


More efficient use of energy


 






Cons:






Higher initial capital cost


More complex parts – harder to maintain


Rotary Screw Compressors


Rather than using pistons, rotary screw compressors rely on rollers to do the compression. Rollers are positioned just off the middle of the central shaft to ensure that one side of the roller is always in contact with the wall. The rollers are powered, rotating extremely fast, causing the same result as scroll compressors: they draw in air at a low pressure and force it out at a higher pressure.






Pros and Cons of Rotary Screw Compressors






Pros:






Good power capacity


Lower initial capital price


Easy to maintain


Cons:






Limited cooling abilities


Require continuous maintenance checks


How Do Low Noise Air Compressors Work?


One complaint often heard around air compressors is that some of them are noisy due to friction and a power source, which can be distracting and inconvenient for both commercial and domestic use. The industry has risen to deal with these complaints however, and there are several low noise air compressors to choose from, offering a decibel rating of around 40 dB.






40 dB is considered low noise; 60 dB is considered the safest decibel level for compressors; anything over 85 dB could cause long-lasting damage to your hearing, and you should avoid being exposed to this level for extended periods of time.






Low noise and silent air compressors are available in both oil-free and oil-based versions, so just how is the silencing effect achieved?






As well as choosing compressors with low decibel levels, one aspect of this technology that makes a big difference is the inclusion of an acoustic chamber for containing the noise. Another tip is to opt for electric-powered compressors, rather than gas-powered, as the former type of power source makes for a quieter machine.






The Bottom Line


Which type of air compressor you go for depends on a variety of factors. You first need to consider what application the compressors will be used for? Do you need it for continuous, ongoing use in large industrial machinery, or will it be used sporadically? Your answers to these questions will help you decide on whether to go for variable or fixed speed compressors.






Another question that you must factor into your decision is: how much do you want to spend? Remember that the initial price of a quality compressor is not the only expense associated with a compressor; consider also the cost of the power needed to run the machine, plus any related ongoing maintenance and repair costs. How much time and energy will investing in high quality compressors save your company? These are all important calculations that should be made before making your decision.






Get in touch below if you wish to find out more.

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  Effectiveness of Air Filters and Air Cleaners in Allergic Respiratory Diseases
Enviado por: E234B - 18-09-2021, 02:46 AM - Foro: Reglas del Foro - Sin respuestas

Effectiveness of Air Filters and Air Cleaners in Allergic Respiratory Diseases

Effectiveness of Air Filters and Air Cleaners in Allergic Respiratory Diseases


Air filtration is frequently recommended as a component of environmental control measures for patients with allergic respiratory disease. Residential air filtration can be provided by whole house filtration via the home’s heating, ventilation, or air conditioning system, by portable room air cleaners, or a combination of the two. Appliances to filter the sleep breathing zone also have been developed. High-efficiency whole house filtration, high-efficiency particulate air sleep zone air filtration, and high-efficiency particulate air room air cleaners all appear to provide various degrees of benefit. Recent studies of various types of filtration, used alone or as part of more comprehensive environmental control measures, are reviewed.






Keywords: Air cleaner, Air filter, Air filtration, Breathing zone, CADR, Clean air delivery rate, Environmental control, Furnace filter, HEPA, HVAC, Indoor air, Indoor allergens, Intervention measures, Ozone, Particulate matter, PM, Room air cleaner, Sleep breathing zone, Ventilation, Whole house filtration






Environmental control practices (ECPs) are a group of measures recommended to reduce exposure to indoor allergens (eg, dust mites, household pets, cockroaches, mold, mice) or nonallergic triggers (eg, environmental tobacco smoke [ETS], wood smoke, volatile organic compounds, particulate matter [PM]) [1]. Historically, many of the common suggestions have been empiric and not based on scientific data or evidence-based clinical trials. As a better understanding of the impact of the characteristics of housing stock [2, 3] and occupants [4] on the indoor living environment has evolved, more effective measures have been identified. These may include modification of the occupant’s habits, remediation, and/or modification of the dwelling and its furnishings, structure, or ventilation, including the use of air filtration. One major drawback in many ECP studies has been the focus on a single allergen (eg, dust mites [5]) or intervention (eg, room air filtration for cat or dog allergy [6–8]). In fact, most allergic individuals have polysensitivity to multiple allergens. ECPs are therefore much more likely to be beneficial if targeted against triggers or allergens known to be problematic for the individual.






In the case of filtration, little attention has been paid to variations among the various appliances themselves, and no clinical comparisons have been done between the benefits of whole house filtration (WHF) versus those of portable room air cleaners (PRACs). According to the most recent American Housing Survey, 75% of US housing units have ducted forced air heat, while 63% have ducted central air conditioning [9]. When used in combination, these ducted heating systems are termed heating, ventilation, air conditioning (HVAC) systems. HVAC systems offer the opportunity for WHF, but poorly maintained or contaminated systems may actually increase the risk of asthma and other allergic respiratory symptoms [10]. Simple forgetfulness by the occupants in replacing the filter at suggested maintenance intervals may be the most common issue. HVAC service technicians frequently find round air filter that have not been changed for years when providing repair or maintenance services [11]. Dirty filters themselves can become a source for air contamination by allergens, particularly fungal spores [12], and can then be trapped, colonized, and released downstream as the overloaded filter fails [13]. Other issues, including air bypass from poor filter fit and duct leakage, may further confound the effectiveness of filtration in HVAC systems.






A barrier to proof of effectiveness for ECPs is the complexity of the gene–host–environment interactions. Expectations have been tainted by the fact that short-term drug studies of only a few weeks’ or months’ duration can show statistical effectiveness for improvement of symptoms. However, despite major advances in the drugs available for the treatment of allergy and asthma, none have been shown to arrest disease progression permanently. Improved understanding on how to avoid or reduce triggers would be expected to have this benefit. This may not occur in the short term. Observational epidemiology has already led to the recognition of a wide range of triggers found in the indoor environment, ranging from dust mite to diesel exhaust particulates. Applied epidemiologic studies are helpful in understanding targeted avoidance and prevention of disease progression.






Morgan et al. [14], as part of the Inner-City Asthma Study Group, conducted a randomized controlled trial of comprehensive ECPs in 937 children with atopic asthma. All were sensitized, as demonstrated by positive skin test, to at least one indoor allergen. A baseline home evaluation included both direct visual inspections and dust collection from the child’s bedroom. Targeted ECPs were then implemented based on skin testing results and the home evaluation. Interventions included the use of a high-efficiency particulate air (HEPA) room air cleaner in the child’s bedroom if the child was exposed to ETS, sensitized and exposed to cat or dog allergens, or sensitized to mold. The intervention group reported significantly fewer symptoms of asthma during the intervention year and the follow-up year. The maximal number of days with symptoms was lower in the intervention group by 0.82 day per 2-week period in the first year (P?<?0.001) and 0.60 day per 2-week period in the second year (P?<?0.001). This effect is similar to that described in placebo-controlled studies of inhaled corticosteroids. The authors concluded that an “individualized, home-based, comprehensive environmental intervention decreases exposure to indoor allergens, and results in reduced asthma-associated morbidity.” This study and its outcomes represent the current thought that multiple ECPs, but not single interventions, are effective in modulating symptoms of allergic disease.






A recent review of 3,727 adults with asthma by Roy and Wisnivesky [15], using data from the Four-State National Asthma Survey, examined the association between preventive asthma care and comprehensive ECPs. Comprehensive management was defined as the implementation of combinations of at least five of eight measures. Air filtration was found to be the fourth (27.4%) most commonly implemented strategy, preceded only by no smoking (80%), no pets (53.9%), and washing sheets in hot water (43.2%), and followed by pillow covers (23.7%), mattress covers (23.4%), no carpets (14.5%), and use of a dehumidifier (13.8%). A similar study in the pediatric population found the same rate of air filtration (27.4%) use in the households of asthmatic children [16].






The role of air filtration in providing relief for individuals with allergic respiratory illness has been studied for more than 40 years [17, 18]. Prior reviews of air filtration have focused primarily on PRACs and the effect on patient symptom scores [19–21]. Reisman [19] stated that the studies should focus only on IgE-proven disease and HEPA PRACs. Wood [20] concluded that while HEPA PRACs may be an option for cat and dog allergy, there was no evidence they were effective for dust mite or mold allergy. Focusing only on allergies does not take into consideration the effects of PM and other indoor air pollutants. McDonald et al. [21] reported a meta-analysis of the only 10 randomized controlled trials on filtration published from 1973 through 1999. All 10 trials included asthmatic patients. The authors found a small statistically significant improvement in total symptoms and sleep disturbance associated with use of air cleaners, but no improvement in nasal symptoms, medication use, or peak expiratory flow (PEF) values.






In a 2010 rostrum article, Sublett et al. [22??] provided a comprehensive review of air filtration. The authors described the characteristics of airborne particulates, including allergens, to be filtered, and pointed out that the impact of inhalable PM and the effect on disease is not always IgE mediated. Residential air-cleaning products and devices are categorized into two broad categories: WHF (ie, filters or cleaners that are installed on the central HVAC system) and free-standing PRACs. Current standards for testing to determine the American Society of Heating, Refrigeration, and Air-Conditioning Engineer’s (ASHRAE) minimum efficiency rating value (MERV) for furnace filters and the Association of Home Appliance Manufacturers rating system clean air delivery rate (CADR) for room air cleaners are outlined. They also described the results of 18 studies on air filtration from 1973 to 2009, including some studies previously reviewed. The authors concluded that for the “optimal choice of cleaning devices, initial cost and ease of regular maintenance should be considered. PRACs with HEPA filters, especially those that air breather filter the breathing zone during sleep, appear to be beneficial. For the millions of households with forced air HVAC systems, regular maintenance schedules and the use of high-efficiency disposable filters appear to be the best choices.” They, as had previous reviewers, recommended that more rigorous study methods be applied to future research on air filtration and that the studies be of sufficient duration to show effectiveness.






Since the Wood [20] and McDonald et al. [21] reviews, there have been 14 studies (Table 1) published that are applicable to the role of air filtration as an environmental control measure for allergic respiratory diseases.






Urbanization increased population density in cities and consequently leads to severe indoor air pollution. As a result of these trends, the issue of sustainable and healthy indoor environment has received increasing attention. Various air filtration techniques have been adopted to optimize indoor air quality. Air filtration technique can remove air pollutants and effectively alleviate the deterioration of indoor air quality. This paper presents a comprehensive review on the synergistic effect of different air purification technologies, air filtration theory, materials and standards. It evaluated different air filtration technologies by considering factors such as air quality improvement, filtering performance, energy and economic behaviour, thermal comfort and acoustic impact. Current research development of air filtration technologies along with their advantages, limitations and challenges are discussed. This paper aims to drive the future of air filtration technology research and development in achieving sustainable and healthy building ventilation.






The most effective ways to improve your indoor air are to reduce or remove the sources of pollutants and to ventilate with clean outdoor air. In addition, research shows that filtration can be an effective supplement to source control and ventilation. Using a portable air cleaner and/or upgrading the cone air filter in your furnace or central heating, ventilation, and air-conditioning (HVAC) system can help to improve indoor air quality. Portable air cleaners, also known as air purifiers or air sanitizers, are designed to filter the air in a single room or area. Central furnace or HVAC filters are designed to filter air throughout a home. Portable air cleaners and HVAC filters can reduce indoor air pollution; however, they cannot remove all pollutants from the air.






The following publications provide information on portable air cleaners and on HVAC and furnace filters commonly used in homes.






Heating ventilation and air conditioning system (HVAC) is very important for offices building and human health. The combining filter method was used to reduce the air pollution indoor such as that particulate matter and gases pollution that affected in health and productivity. Using license plate frame in industrial HVAC systems (factories and manufacturing process) does not enough to remove all the indoor pollution. The main objective of this study is to investigate the impact of combination filters for particle and gases removal efficiency. The combining method is by using two filters (particulate filter pre-filter and carbon filter) to reduce particle matter and gases respectively. The purpose of this study is to use minimum efficiency reporting value (MERV filter) rating 13 and activated carbon filter (ACF) to remove indoor air pollution and controlling the air change rate to enhance the air quality and energy saving. It was concluded that the combination filter showed good removal efficiency of particle up to 90.76% and 89.25% for PM10 and PM2.5 respectively. The pressure drop across the filters was small compared with the high-efficiency filters. The filtration efficiency of combination filters after three months' was better than efficiency by the new MERV filter alone.

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  Recent trends and future of pharmaceutical packaging technology
Enviado por: E234B - 18-09-2021, 02:44 AM - Foro: Reglas del Foro - Sin respuestas

Recent trends and future of pharmaceutical packaging technology

Recent trends and future of pharmaceutical packaging technology


The pharmaceutical package market is constantly advancing and has experienced annual growth of at least five percent per annum in the past few years. The market is now reckoned to be worth over $20 billion a year. As with most other packaged goods, pharmaceuticals need reliable and speedy packaging solutions that deliver a combination of product protection, quality, tamper evidence, patient comfort and security needs. Constant innovations in the pharmaceuticals themselves such as, blow fill seal (BFS) vials, anti-counterfeit measures, plasma impulse chemical vapor deposition (PICVD) coating technology, snap off ampoules, unit dose vials, two-in-one prefilled vial design, prefilled syringes and child-resistant packs have a direct impact on the packaging. The review details several of the recent pharmaceutical packaging trends that are impacting packaging industry, and offers some predictions for the future.






Packaging is defined as the collection of different components which surround the pharmaceutical raw material from the time of production until its use. Packaging pharmaceutical products is a broad, encompassing, and multi-faceted task. Packaging is responsible for providing life-saving drugs, medical devices, medical treatments, and new products like medical nutritionals (nutraceuticals) in every imaginable dosage form to deliver every type of supplement, poultice, liquid, solid, powder, suspension, or drop to people the world over. It is transparent to the end user when done well and is open to criticism from all quarters when done poorly.[1,2]






Distribution of products is now more global than ever. Mass customization of packaging to permit its use in multiple markets is a topic that needs exposition and discussion. Environmental issues, including sustainability, will always be a subjective dimension to any packaging design.






Packaging is an emerging science, an emerging engineering discipline, and a success contributor to pharmaceutical industries.






Packaging can reside, or report through research and development (R and D), engineering, operations, purchasing, marketing, or the general administrative department of a company. For the majority of products produced in pharmaceutical industries it is probably the single largest aggregate purchase made by a company of materials critical to the protection, distribution, and sale of the product.


Containment - The containment of the product is the most fundamental function of packaging for medicinal products. The design of high-quality packaging must take into account both the needs of the product and of the manufacturing and distribution system. This requires the packaging: not to leak, nor allow diffusion and permeation of the product, to be strong enough to hold the contents when subjected to normal handling and not to be altered by the ingredients of the formulation in its final dosage form.[3]






Protection - The packaging must protect the product against all adverse external influences that may affect its quality or potency, such as light, moisture, oxygen, biological contamination, mechanical damage and counterfeiting/adulteration.






Presentation and information - Packaging is also an essential source of information on medicinal products. Such information is provided by labels and package inserts for patients.






Identification - The printed packs or its ancillary printed components serves the functions of providing both identity and information.






Convenience - The convenience is associated with product use or administration e.g., a unit dose eye drop which both eliminates the need for preservative and reduces risks associated with cross infection, by administering only a single dose.


Primary packaging system is the material that first envelops the product and holds it i.e., those package components and subcomponents that actually come in contact with the product, or those that may have a direct effect on the product shelf life e.g., ampoules and vials, prefilled syringes, IV containers, etc.






Secondary packaging system is outside the primary packaging and used to group primary packages together e.g., cartons, boxes, shipping containers, injection trays, etc.






Tertiary packaging system is used for bulk handling and shipping e.g., barrel, container, edge protectors, etc.






Traditionally, the majority of medicines (51%) have been taken orally by tablets or capsules, which are either packed in blister packs (very common in Europe and Asia) or fed into plastic pharmaceutical glass bottle (especially in the USA). Powders, pastilles and liquids also make up part of the oral veterinary medicine intake. However, other methods for taking medicines are now being more widely used. These include parentral or intravenous (29%), inhalation (17%), and transdermal (3%) methods.






These changes have made a big impact on the packaging industry and there is an increasing need to provide tailored, individual packaging solutions, which guarantee the effectiveness of medicines.[4]






The present review article details several key trends that are impacting packaging industry, and offers some predictions for the future packaging encompassing solid oral dosage forms and injectables.






Aseptic blow-fill-seal (BFS) technology is the process by which plastic containers are formed, filled with sterile filtered product and sealed in an uninterrupted sequence of operations within the controlled sterile environment of a single machine.[5,6]






The blow-fill-seal process is a robust, advanced aseptic processing technology, recognized by worldwide regulatory authorities for its inherent operational advantages over conventional aseptic production. Blow-fill-seal systems offer a unique combination of flexibility in packaging design, low operating cost and a high degree of sterility assurance. The machines require a minimum number of operating personnel and have a relatively small space requirement.






A variety of polymers may be used in the process, low and high-density polyethylene and polypropylene being the most popular. The innate ability to form the container/closure during the actual aseptic packaging process allows for custom design of the container to meet the specific needs of the application. This flexibility not only improves container ease of use, but provides a means of interfacing with many of today's emerging drug delivery technologies, most notably in the field of respiratory therapy.






Thermoplastic is continuously extruded in a tubular shape [Figure 1a]. When the tube reaches the correct length, the mold closes and the parison is cut [Figure 1b]. The bottom of the parison is pinched closed and the top is held in place with a set of holding jaws. The mold is then transferred to a position under the filling station.






The nozzle assembly lowers into the parison until the nozzles form a seal with the neck of the mold [Figure 1c]. Container formation is completed by applying a vacuum on the mold-side of the container and blowing sterile filtered air into the interior of the container. The patented electronic fill system delivers a precise dosage of product into the container. The nozzles then retract into their original position.






Container sealing


Following completion of the filling process, the top of the container remains semi-molten. Separate seal molds close to form the top and hermetically seal the container [Figure 1d]. The mold opens and the container is then conveyed out of the machine [Figure 1e].






The cycle is then repeated to produce another filled container. The filled containers are tested and checked to ensure that they meet the very strict specifications laid down for such products.






The duration of the complete cycle is between 10-18 seconds, depending on the container design and the amount of liquid to be filled.






BFS technology offers considerable advantages over conventional aseptic filling of preformed (plastic or other) containers, which are described as follows:






BFS technology reduces personnel intervention making it a more robust method for the aseptic preparation of saccharin sodium.






There is no need to purchase and stock a range of prefabricated containers and their closures. Bulk containers of plastic are required.






Cleaning and sterilization of prefabricated containers and closures is not required. A clean, sterile container is made within the BFS machine as it is required for filling.






The cost of material transport, storage and inventory control is reduced.






Validation requirements are reduced.






The technology allows the design of high-quality, custom-designed containers with tamper-evident closures in a variety of shapes and sizes.






There is a large choice of neck and opening device shapes.






A single compact BFS machine takes the place of several conventional machines, saving floor space. In addition, zones for transport to successive filling and closing procedures are not required because these operations all take place in the BFS machine itself.






The operation of BFS machines is less labor intensive than conventional aseptic filling.






The code numbers and variable data such as batch number and expiry date can be molded into the container itself rather than being added at a subsequent stage.






The process lends itself to the production of single dose containers and therefore preservatives are not necessary as they are with multi-dose containers.






Blow-fill-seal technology has gained much market focus in recent years due to the increased focus on biologics, proteins and other complex solutions. These important products often cannot withstand exposure to high temperatures for extended periods of time without degradation of their active components. Conventional terminal sterilization, therefore, is not an acceptable method to produce a ‘sterile’ product. Bulk sterilization, sterilization by gamma irradiation or filter sterilization followed by direct packaging utilizing the blow-fill-seal process are often used successfully for these types of products.






Counterfeiting means producing products and packaging similar to the originals and selling the fake as authentic products. Counterfeit is a problem of product security, with reference to packaging is not a problem in isolation; it is the part along with:






Duplication - i.e., copying labels, packaging, products, instructions and usage information,






Substitution - placing inferior products in authentic or reused packaging,






Tampering - by altering packages/labels and using spiked, pilfered, or stolen goods in place as real,






Returns and Warranty frauds they are addressed as Brand Theft.






The current numbers of anti-counterfeiting solutions are many and new options are introduced in the market with some variations. An attempt is made to explain the technologies for easy understanding on product packaging.






1. Overt (visible) features


Overt features are intended to enable end users to verify the authenticity of a pack. Such features will normally be prominently visible, and difficult or expensive to reproduce. They also require utmost security in supply, handling and disposal procedures to avoid unauthorized diversion. They are designed to be applied in such a way that they cannot be reused or removed without being defaced or causing damage to the pack for this reason an overt device might be incorporated within a tamper evident feature for added security.






Tamper evident packaging systems


Some packages are inherently tamper proof, like a tin can hermetically sealed, an aseptically packed multilayer carton or a vacuum or the retort pack. The tamper evident packaging systems are:






a) Film wrappers


A transparent film with a distinctive design is wrapped securely around a product or product container. The film must be cut or torn to open the container and remove the product. Substrates options include ultra destructible films, voidable films that provides image when removed. e.g., Solvent sensitive papers.






b) Shrink seals and bands


Bands or wrappers with a distinctive design are shrunk by heat or drying to seal the cap and container union. The seal must be cut or torn to remove the product.






c) Breakable caps


Such caps break when an attempt is made to open it. These caps provide external tamper evidence and can also be combined with the internal seals thereby providing double security.






d) Sealed tubes


The mouth of the tube is sealed, and the seal must be punctured to obtain the product.






2. Covert (hidden) features


The purpose of a covert feature is to enable the brand owner to identify counterfeited product. The general public will not be aware of its presence nor have the means to verify it. A covert feature should not be easy to detect or copy without specialist knowledge, and their details must be controlled on a “need to know” basis. If compromised or publicized, most covert features will lose some if not all of their security value [Figure 2].






Radio frequency identification (RFID) is hardly a new concept. For some, RFID is already a mainstream technology-it is used every day to pay tolls, secure building access, catch shop lifters etc., It allows the identification of objects through a wireless communications in a fixed frequency band. Three essential components in any RFID system are: the tag, the reader and the software. The tag is an integrated circuit containing a unique tracking identifier, called an electronic product code (EPC), which is transmitted via E.M. waves in the radio spectrum. The reader captures the transmitted signal and provides the network connectivity between tag data and the system software. The software can be tailor made for the purpose of anti-counterfeiting. For their track and trace usage, RFID tags are used [Figure 3].






When RFID tag is within the interrogation zone of the reader (i.e., interrogator) equipment; sufficient power is extracted from the interrogator to power up the tag or circuit, or a special reflective material. It then responds by transmitting data back to the interrogator.






b) Active tag


Such tags incorporate a battery to increase range for collating data, tag to tag communication, etc., But these are much more expensive.






c) Semi-active tag


In these tags batteries are used to back up the memory and data, but not to boost the range. With some active RFID tags, the batteries are only used when interrogated or when sending a homing pulse at fixed intervals to reduce cost and size.






4. Packaging designs: Materials/Substrates and other design options


a) Substrates


There are variety of substrates used in the design of packages with intent to provide counterfeit and tamper evident features starting from litho paper, polystyrenes, destructive vinyl's, acetate films synthetic paper and coatings etc., There are many ways of incorporating covert markers within a substrate, such as visible or UV fluorescing fibers, or chemical reagents in carton board or paper. Watermarks can be embedded in leaflet paper, or metallic threads interwoven in the base material, possibly including an overt optically variable devices (OVD) feature. These require a dedicated supply source and large volume production, which, if affordable, results in a very effective option. Micro-encapsulated distinctive odors can be applied as an additive to an ink or coating to provide a novel covert or semi-overt feature, as well as sound chips creates special opportunities in the design.






b) Packaging designs


Packaging designs like sealed cartons, aerosol containers have inherent strength against counterfeiting






c) Sealing systems


Special caps such as the outer tamper evident system or the foil seal as an internal tamper evident feature are commonly used for pharmaceutical products. Sealing options are lever-lidded tins, secure packaging tapes, lined cartons and tear tapes/bands.






5. Security labels


Tamper evident and security labels play an important role in providing some relief to the consumers against fakes. In self adhesive labels the substrate mostly performs as a complimentary interaction of the substrate and the pressure sensitive adhesive. While passive security labels have been extensively used, today one can find a greater application of functional labels such as printing plus anti-theft. Some label options are:






a) Paper labels with security cuts


The substrate used for these labels is ordinary coated/uncoated paper. The security features are built in by the label printer at the converting stage. With the help of a special cutting die, the face material is given cuts at various angles so that by any ways one tries to remove these labels the paper will tear off. A general purpose permanent adhesive works fine with such labels. Care is taken to ensure that the adhesive will adhere well and firmly to the surface on which the label has to be applied.






b) Destructible labels


Needs a special substrate designed for the purpose. Most of the high-end applications use a specially made cellulose acetate film. The film is very intricately designed so that it has adequate strength to undergo conversion into label stocks in roll form. It is available both in clear and opaque formats and further converted into labels using aggressive pressure sensitive adhesives. The labels can be automatically dispensed on automatic label dispensers and when attempted to be removed, break-up into very small fragmented pieces. The cost effective vinyl have replaced acetate film. A combination of various synthetic polymers can be used to impart low inherent strength to the substrate.






c) Void labels and tapes


The most important of the tamper evident security labels and have text built into them. When as a self adhesive label they are removed, they exhibit the word VOID both in the removed film and the adhesive layer left behind. These substrates gain importance as there can be customization built into the labels produced with it. One can use polyester or biaxially-oriented polypropylene (BOPP) as face materials. Variety of colors, even metallization is possible. The text VOID could be replaced by the customers brand, emblem or a message, which would normally be invisible till the label is opened. Due to the versatility of things that can be done with the product, these label substrates have found widespread usage worldwide. The substrates can even be designed to work as tapes for the final outer corrugated cartons to prevent pilferage.






d) Self destructing paper label


The labels are very similar to destructible labels as mentioned earlier. In this case, the substrate used is of very weak strength paper of low grammage. The paper is also heavily loaded with fillers creating a weak and brittle paper. Labels made from such papers fragment into pieces when attempted to be removed. However, converting it is a very tricky issue when using these substrates due to the lack of strength. The papers are very difficult to source since most of the paper mills are trying to develop papers with very high strength.






e) Holographic labels


The labels form a very large and important part of the security label market and are an ideal choice for product authentication. The holographic foil that is an optically variable device is largely made using a polyester film base. The optical interaction of the holographic image and the human eye makes it ideal for brand promotion and security. These products reveal the holographic image when tilted in light. The image so revealed can be customized to the need of the brand owners to make the maximum impact. The hologram production involves development of complex origination process and a lot of innovation to make it difficult for counterfeiters to duplicate. Many holograms are designed such that besides offering brand authentication they also have tamper evident properties. The top polyester layer has a special coating that if the hologram is attempted to be removed, the top layer peels off leaving the hologram behind on the product [Figure 4].

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