Buying a diamond can be an exhilarating but daunting adventure, especially if you're a newbie.
If I could offer only one piece of advice it would be this: "Learn as much as you can about the 4Cs before you go shopping."
For the uninitiated, that's cut, color, clarity and carat weight. And I like to add one more – common sense.
Choosing the perfect diamond (and there's no such thing as the "perfect" diamond, although a few have come close) is as much a matter of personal taste as it is a matter of the diamond's characteristics.
Some couples are willing to forego quality for size, others prefer the brilliance of a flawless blue-white diamond over a larger stone with less clarity.
You be the judge – but not until you're clear about those characteristics I mentioned. I suggest you read our Diamond Buying Guide , or go to one of the quality online jewelers such as http://www.bluenile.com or http://www.mondera.com .
Talk to any jeweler and they'll all give you a different opinion as to what they believe is the most important quality of a diamond.
According to Mayer Herz, Vice President of Diamond Acquisition at Mondera.com, "Cut is the most important consideration if you're on a budget.
However, Joseph Schlussel, Publisher of Diamond Registry Bulletin, says "I personally believe that color is the most important thing. eye. I would put cut the last, because most people can not see it. "
The safest all-round bet is to look for the overall "package", with the levels of cut, clarity, color and size as good as you can get for the price you're willing to pay.
Here are my tips to help you get the best value possible:
* Ensure you get a Gemological Institute of America (GIA) or the American Gem Society (AGS) Certificate when you purchase your diamond. A Certificate guarantees that you are getting what you paid for.
* If you are buying at a retail store, ask to see your diamond against a white cloth (or take your own – even a white piece of paper will do the trick!). Jewelers typically use a black felt cloth to display their stones because all diamonds look white against black.
* The American Gem Society says that the cut of the diamond can increase the price by as much as 50%. A well-cut diamond, when viewed from above, will sparkle with a brilliance you will not find in any other precious stone.
* Most diamonds have flaws (called inclusions) that developed during its formation millions of years ago. Some are impossible to see with the naked eye, others glare at you. The more inclusions, the poorer the quality of the diamond, and the less light it will emit. But its all a trade-off – fewer inclusions means a more expensive diamond.
Knowledge is power, and the more you understand about how diamonds are graduated and how that determines the price you'll pay, the better you'll be able to judge what is good value.
Above all, remember that you'll be the one wearing it, and hopefully for a long time, so the final decision is yours. My very first diamond had a hairline crack deep inside it, and I came to love that diamond as much for its tiny flaws as I loved my husband for his!
Source by Alex Miller
The business of wholesale distributing is one of the oldest and most profitable businesses in history. One of the reasons is because you don’t need to be there all the time to make money; you have lots of other businesses selling the items for you. These businesses are your customers. People that buy from you to resell the products and make money themselves. They can be wholesalers themselves or they can be retailers. Either way, it’s a way to multiply your sales.
Did you ever wanted to start a business? Chances are that any business will have something to do to with the “wholesale business”. Most businesses have to buy goods at wholesale or have to buy supplies at wholesale prices. If you have a restaurant you don’t go to the market to buy food at retail prices, you have a wholesale distributor called “foodservice distributor” deliver your products. If you have any time of retail store or business you need wholesale suppliers. Even if you provide a service like a doctor or a hair stylist chances are you are buying supplies at wholesale prices. Wholesalers are everywhere and they are involved with almost every business in the world.
The best thing about this business is that you can make sales when you are not there. Once you get a few stores as customers you will see how they will sell your products over and over again while you are at home, on vacation, with friends and family. You deliver them, they sell them!
Multiplying your sales is probably one of the most important factors in wholesale distribution. It’s what makes this business interesting. It’s not just you working and making money on an hourly basis, you have many people working many hours to make money and in turn make you money. When you are a good distributor with a good product and good service, people will come to you. They will find you and they will keep buying from you. Why? Because that’s their business, that’s how they make their money. You would do the same thing. If you have a supplier with fast selling products you’ll keep buying from the supplier because you keep moving the merchandise. This is why even very small one man operations can make money in this business. Even if they sell what everyone else is selling. Even if they are more expensive. Why, because they are there. They have good service and if you are a retailer you know that you need products to sell products. If your shelves are empty because your supplier is not there, you are losing money. It does not matter if your supplier has the best price, if he does not have good service you won’t have a long relationship with them.
In the next few chapters you will learn the different types of distribution business out there, the types of products and services you can sell, and how much you can make with each one.
When you are reading the types of wholesale businesses try and see yourself doing each of these tasks or running each of those businesses. If you like a particular business, highlight it and do some research on it. There are many things you can do in wholesale and distribution depending on your personality, your cash situation and your goals.
Copyright 2006 Jorge Olson
Source by Jorge Olson
Today’s systems are designed to meet stricter environmental, indoor air quality and user requirements. Many of the gains in HVAC system efficiency have come as the result of improvements in the operating efficiency of key system components. Other gains are the result of the use of technologies that are either new, or new to the HVAC field. Even the use of computer-aided design tools have helped system engineers design HVAC systems that perform more efficiently.
Although there are many individual advances that have helped to improve HVAC system operating efficiency, much of the overall improvement can be attributed to five key factors:
– The development of low kW/ton chillers;
– The use of high-efficiency boiler control systems;
– The application of direct digital control (DDC) systems;
– The use of energy-efficient motors; and,
– The matching of variable frequency drives to pump, fan and chiller motors.
For years, building owners were satisfied with the performance and efficiencies of chillers that operated in the range of 0.8 to 0.9 kW/ton when new. As they age, actual operating efficiencies fall to more than 1.0 kW/ton at full load.
Today, new chillers are being installed with full load-rated efficiencies of 0.50 kW/ton, a near 50 percent increase. Equally impressive are the part-load efficiencies of the new generation of chillers. Although the operating efficiency of nearly all older chillers rapidly falls off with decreased load, the operating efficiency of new chillers does not drop off nearly as quickly.
Chiller design changes
Several design and operation changes have helped improve chiller performance. To improve the heat transfer characteristics of the chillers, manufacturers have increased the size of the units’ heat exchangers. Electromechanical control systems have been replaced by microprocessor-based electronic controls that provide greater precision, reliability and flexibility. Variable frequency drives control the speed of the compressor, resulting in an increase in part-load performance.
Increased energy efficiency is not the only benefit of the new generation of building chillers; these chillers offer better refrigerant containment. Although older chillers routinely may have lost 10 percent to 15 percent of the refrigerant charge per year, new chillers can limit losses to less than 0.5 percent. Lower leak rates and better purge systems reduce the quantity of non-condensable gasses found in the refrigerant system — a key factor in maintaining chiller performance over time.
Another significant development is in boiler operation: the replacement of pneumatic and manual controls with microprocessor-based systems. As a rule of thumb, the systems can be expected to achieve energy savings of 5 percent to 7 percent over conventional pneumatic-based systems.
Microprocessor-based control systems achieve their savings primarily as the result of their ability to modulate the boiler’s operation more accurately than pneumatic-based systems. By modulating the boiler’s operation accurately, the systems help to maintain the proper fuel-to-air ratio and track the load placed on the boiler by the HVAC system.
Microprocessor-based systems offer several additional advantages, including remote monitoring and operating capabilities, automated control sequences, monitoring of steam flow, and reduced maintenance costs. One way the systems can help reduce maintenance costs is through their ability to maintain proper fuel-to-air ratio. By maintaining the proper ratio, the systems reduce the rate at which soot collects on boiler tubes, thus decreasing the frequency of required tear down and cleaning. Keeping the boiler tubes clean of soot also helps to improve the thermal efficiency of the boiler.
Direct digital controls
A major change in the HVAC field is the widespread implementation of direct digital controls (DDC). Introduced more than 15 years ago, DDC systems have become the industry standard for control systems design today. With the ability to provide accurate and precise control of temperature and air and water flows, the systems have widely replaced pneumatic and electric control systems.
DDC systems help building owners save energy in several ways. Their accuracy and precision nearly eliminate the control problems of offset, overshoot, and hunting commonly found in pneumatic systems, resulting in better regulation of the system. Their ability to respond to a nearly unlimited range of sensors results in better coordinated control activities. This also allows the systems to perform more complex control strategies than could be performed with pneumatic controls. Finally, their simple or automatic calibration ensures that the control systems will perform as designed over time, with little or no loss of accuracy.
DDC systems also offer several other advantages. Because the control strategies are software-based, the systems can be easily modified to match changes in occupant requirements without costly hardware changes. DDC systems also are ideal for applications that benefit from remote monitoring and operation.
Today’s HVAC systems are making use of energy-efficient motors. Energy-efficient motors offer a moderate but significant increase in full-load operating efficiency over standard motor designs. For example, an energy-efficient 10 hp motor operates at about 93 percent efficiency; a standard motor of the same size is typically rated at 88 percent. Similarly, a 50 hp energy-efficient motor is rated at approximately 94 percent efficiency in contrast to the 90 percent efficiency rating of a 50 hp standard motor.
This increase in operating efficiency accompanies a first-cost increase for the motors. How rapidly this additional first cost is recovered depends on two factors: the loading of the motor, and the number of hours the motor is operated per year.
The closer the motor is operated to its full-load rating and the greater the number of hours per year the motor is operated, the quicker the first-cost differential is recovered. For most applications where the motor is run continuously at or near full load, the payback period for the additional first cost is typically between three and six months.
The combination of constant loading and long hours of operation have made HVAC applications well-suited for the use of energy-efficient motors. Energy-efficient motors commonly are found driving centrifugal circulation pumps and system fans. With these loads, the 4 percent or 5 percent increase in the electrical efficiency of the drive motor translates to a significant energy savings, particularly when the systems operate 24 hours per day, year round.
A side benefit of energy-efficient motor design is its higher power factor. Increasing the power factor of a drive motor reduces the current draw on the electrical system, frees additional distribution capacity and reduces distribution losses in the system. Although increasing the power factor isn’t enough of a benefit to justify the cost differential of the higher efficiency motor, it’s an important consideration, particularly for large users of electricity where system capacity is limited.
Although the motors have demonstrated themselves to be very cost-effective in new applications, their use in existing applications is a little more difficult to justify. In most instances, the cost to replace an existing, operating motor with one of higher efficiency will not be recovered for five to 10 years or longer.
Of the improvements in HVAC systems that have helped to increase operating efficiency, variable frequency drives have had the most dramatic results. Applied to system components ranging from fans to chillers, the drives have demonstrated themselves to be very successful in reducing system energy requirements during part-load operation. And with most systems operating at part-load capacities 90 percent or more of the time, the energy savings produced by variable frequency drives rapidly recover their investment, typically within one to two years.
In general, the larger the motor, the greater the savings. As a rule of thumb, nearly any HVAC system motor 20 hp and larger can benefit from the installation of a variable frequency drive.
Variable frequency drive applications
Variable frequency drives produce their savings by varying the frequency and voltage of the motor’s electrical supply. This variation is used to reduce the operating speed of the equipment it controls to match the load requirements. At reduced operating speed, the power draw of the drive motor drops off rapidly.
For example, a centrifugal fan, when operated at 75 percent flow, draws only about 40 percent of full-load power. At 50 percent flow, the power requirement for the fan decreases to less than 15 percent of full-load power. While conventional control systems, such as damper or vane control, also reduce the energy requirements at partial flow, the savings are significantly less.
Another area where variable frequency drives have improved the operating efficiency of an HVAC system is with centrifugal pumps found in hot and chilled water circulation systems. Typically, these pumps supply a constant flow of water to terminal units. As the demand for heating or cooling water decreases, the control valves at the terminal units throttle back. To keep the pressure in the system constant, a bypass valve between the supply and return systems opens. With the flow rate remaining nearly constant, the load on the pump’s electric drive also remains nearly constant.
Variable frequency drives regulate the pressure in the system in response to varying demands by slowing the pump. As with centrifugal fans, the power required by the pumps falls off as the load and speed are decreased. Again, because most systems operate well below design capacity 90 percent of the time, the savings produced by reduced speed operation are significant, typically recovering the cost of the unit in one to two years.
A third application for variable frequency drives is centrifugal chillers. Chillers are sized for peak cooling loads, although these loads occur only a few hours per year.
With conventional control systems that close vanes on the chiller inlet, chiller efficiency falls off significantly during part-load operation. When variable frequency drives are applied to these chillers, they regulate the operation of the chiller by reducing the speed of the compressor. The result is near full-load operating efficiency over a very wide range of cooling loads. This increase in part-load efficiency translates into a 15 percent to 20 percent increase in the chiller’s seasonal efficiency.
Energy conservation isn’t the only benefit of variable frequency drives. A strain is placed on an electric motor and the mechanical system it drives every time a pump, fan or chiller is started at full-line voltage: Motor winding becomes heated, belts slip, drive chains stretch and high-pressure is developed in circulation systems. Variable frequency drives reduce these stresses by starting systems at reduced voltages and frequencies in a soft start, resulting in increased motor and equipment life.
Finally, the most important element in an energy-efficient HVAC system is how the system is operated. No matter how sophisticated the system, or how extensive its energy-conserving features, the system’s performance depends upon the way in which it’s operated and maintained. Operating personnel must be properly trained in how best to use the system and its features. Maintenance personnel must be trained and equipped with the proper tools to keep the system operating in the way it was designed. Maintenance cannot be deferred.
Energy-efficient HVAC systems offer the facility manager the ability to improve system performance while reducing energy requirements. But they benefit building owners only as long as they are taken care of. If facility managers choose to ignore maintenance requirements, they may soon find systems malfunctioning to the point where they have actually increased the requirement for energy.
Source by Julian Arhire
If you want a completely self sufficient alternative energy power source, there are very few choices. Sure, there are a lot of renewable energy power systems, solar, wind, and others, but there are draw backs with these sources. One of them is that some are not that widely available, like geothermal, and water turbine electricity. Solar is a very popular form of renewable energy, and can be used just about anywhere, but there are drawbacks to this as well. One of them of course is that the sun is only available half the day, and without battery backup to store surplus solar energy, you are left in the dark at night. Then what if you live in an area where there are four seasons? In the winter, the sun shine is hit or miss, and sometimes does not come out for days.
Wind turbines are also a good idea, but they too have drawbacks. For one, you need a certain amount of wind to turn the turbine enough to produce the minimum require electricity. While you can make vertical axis turbines that are smaller and are able to pick up wind at lower speeds, unless you live in an area where there is a constant supply of wind, then this type of power source is not going to be that efficient . You can combine the two, solar with wind, but again, there are the draw backs mentioned.
But wait, there's hope yet. While certainly not new, magnetic generators have been suppressed for a long time, mainly by big business power companies who say that these types of alternative power sources are not reliable. NOT TRUE. In fact, magnetic generators work better than people think, are not that expensive to make, and can be as small as a regular emergency generator. These systems do not rely on the wind, or the sun, or really any kind of external energy source, therefore can be used anywhere on the planet.
Learn more at http://www.magneticenergynow.info
The principle of magnetic generators is relatively simple, and any one who has played with magnets can understand the concept. Using the repelling force of magnets, you can set in motion a generator that creates an electromagnetic field, producing free and abundant electricity. The generator is set up with two sets of magnets, one on the generating cylinder, and the other set inside the outer casing. These magnets push away from each other, causing rotation and a electrical field. Once set in motion, they will continue to spin indefinitely, without much maintenance at all. The faster they spin, the more electricity is created.
You can find DIY magnetic generator plans online, and through various companies. These kits come complete with all the instructions, lists of parts and diagrams on how to build your own. You can even buy most of the necessary materials from local hardware and home improvement outlets, bringing the cost of making these kinds of power sources down quite considerably. The actual cost depends a lot on where you get the DIY kits from, and where you buy the supplies, but suffice it to say that you can spend under $ 500 on one of them, much less than the cost of some of the other alternative power sources.
Source by Jo R