Items for Autoclaving

May 16th, 2014 by Acmas No comments »

Autoclave uses moist heat sterilization for sterilizing and decontaminating the equipments. Autoclave sterilizes the equipments by subjecting them to high pressure saturated steam at 121 degree C and 15 pounds of pressure per square inch depending for around 15-20 minutes on the size of the load and the contents.

As autoclave works by allowing steam to enter and maintaining extremely high pressure for at least 15 minutes therefore heat labile products cannot be sterilized using the autoclave such as plastics etc. Some materials present specific hazards when autoclaved such as production of toxic or noxious gases. There is a limit for the materials which can be autoclaved and which cannot. (As stated earlier heat labile articles cannot be autoclaved).

Articles that can be autoclaved are listed below;

  • Glass wares such as beakers, conical flasks glass rods and knifes.
  • Cultures and stocks of infectious material.
  • Culture dishes and related devices.
  • Culture media (Luria agar and Luria broth).
  • Discarded live and attenuated vaccines.
  • Contaminated solid items such as: Petri dishes, Eppendorf, pipette tips, pipettes, gloves, paper towel.

Articles that cannot be autoclaved are listed below;

  • Heat labile products
  • Sealed articles
  • Radioactive elements
  • Volatile articles
  • Chlorinated compounds
  • Corrosive chemicals
  • Articles contaminated with chemotherapeutic agents
  • Some plastics
  • Articles that can be denatured under the steam.

Insect Growth Chamber- Behavioral study of insects

May 16th, 2014 by Acmas No comments »

Insects are the largest group of Arthropods. There are over 800,000 different types of insects. Insects are very adaptable, living almost everywhere in the world. Common insects include the fly, beetle, butterfly, moth, dragonfly, bee, wasp and praying mantis. Insects have an exoskeleton that covers their entire body. An insect’s body consists of 3 parts: the head, thorax and abdomen.

Insects are beneficial as they pollinate crops, act as natural enemies of damaging pests, and produce useful products for humans. Also, they are harmful as major pets of food crops, vectors for transmitting deadly diseases, and cause damage to our urban infrastructure, environment, forest and natural resources. The study of insect ecology is important to understand their evolution and diversification and their influence on the functional and trophic links between different components of associated habitats.

The Insect Growth Chamber an example of environmental chamber provides a unique high volume solution for a wide variety of entomological studies and offers reliable results for insect rearing experts. Insect growth chamber helps in the behavioral study of insects under environmental conditions such as humidity, temperature and light. Phenol coated refrigeration coils of the insect growth chamber resist the corrosive effects of acids inherent in the rearing of insects.

Entomological studies may help in the prevention of insect borne diseases like malaria and dengue (e.g risk prediction of dengue vector which can be useful for developing dengue vector).

Many insects rely on energy reserves stored in the fall to fuel their breeding biology in the spring. As winter conditions change with climate change, these altered temperatures will affect the energetic of overwintering in many insects. Investigating these effects, using the climate control available in the insect growth chamber one can get the useful data/information that will be valuable for both conservation of biodiversity and the prediction and management of some pest insects.

Many insects migrate in response to both predictable and unpredictable habitat deterioration, using environmental cues to evaluate habitat quality. By examining the ecology and physiology of insect migration under controlled environmental condition, one can generate the data that will not only broaden the basic understanding of the process involved in migration but also allow examining possible consequences of climate change for migratory species.

Some Application areas where Insect growth chamber is useful;

  • Entomological studies
  • Developmental biology
  • Conservation of biodiversity
  • Plant and insect interaction
  • Insect pathogen interaction
  • Insecticide research

Industrial Climate Control Air Curtain

May 14th, 2014 by Acmas No comments »

An Air Curtain is a continuous broad stream of air circulated across a doorway serving a conditioned space. Air curtains are normally mounted horizontally over the door. They can also be mounted vertically at the side of the door or under the floor directed upwards

Air curtains are the best device to control the indoor climate in all the places where the doors cannot always be closed. The main purpose of Air Curtain is to disallow the influx of outside air through opening. Opening where an Air Curtain would typically be used are exterior shipping and receiving doors to plants and warehouses and interior doors between plant areas of different temperatures. These are used not only to prevent cold air from pushing its way in, but also prevent warm air from going outside the door.

In order to control climate an Air Curtain emits an air stream with enough velocity at the nozzle and the width of the nozzle. For different door sizes and different wind conditions, different air velocities at the nozzle are required.

To prevent the entry of outside winds the discharge nozzle is angled outward so that the air leaving it meets the wind trying to enter. The wind meet/strike the Air curtain stream in the doorway. Working principle is shown in the figure below;

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When the vector representing the air stream and the vector representing the wind equalize they form a resultant which should meet the floor in the door plane for maximum efficiency.

The doors on industrial buildings are often open for long periods of time and can be extremely wide, in the case of warehouse doors. With people and delivery vehicles needing access, closing these doors to maintain the internal atmosphere is impractical. An industrial Air Curtain mounted above or to the side of these entrances will create a more comfortable and safer working environment.

For areas that are temperature controlled, Air Curtains act as an invisible barrier sealing in the chilled or heated air, providing unhindered access for staff and removing the inconvenience of fast-acting shutter doors or plastic slats.