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In a '''nuclear photonic rocket''', a [[nuclear reactor]] would generate such high temperatures that the [[blackbody radiation]] from the reactor would provide significant thrust. The disadvantage is that it takes a lot of [[Power (physics)|power]] to generate a small amount of [[thrust]] this way, so [[acceleration]] is very slow. The photon radiators would most likely be constructed using [[graphite]] or [[tungsten]]. Photonic rockets are technologically feasible, but rather impractical with current technology.
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You need to know where, when and why they enrolled. Utilize this information within your messages.<br><br>As soon as your customers are opting in to your list, ensure you at least get their first names. Having their name to reference makes any more communication you have with them more personal and much more likely to catch their attention. In case your messages address readers by name, they are going to feel more individual than anonymous, making your messages or [http://www.pcare.nu/members/angeldollar/activity/4363/ Olympus VR 340] stand above the fray of bulk email.<br><br>The more choices and options you provide in your customers will help to generate an effective email marketing campaign. Allow readers to pick the number of emails they get, how many times they will have them, and the quantity of information about themselves they need to give. Giving control towards the subscriber is likely to make them feel much more comfortable. They will be more likely to sign up.<br><br>In your email promotions, utilize the smallest amount of graphics as you possibly can. Some email readers block graphics automagically and if you are counting on graphics to obtain your message across, some readers won't obtain that message. As well, emails which can be heavily laden with graphics are often seen as junk or spam mail by email programs, meaning your email could land inside a junk folder quickly.<br><br>When researching email marketing, use as numerous resources as you possibly can. There is a helpful information available on the web about this. You can probably locate a number of classes or workshops where you live, so make sure to attend as much as you can.<br><br>Keep the style and format the identical for each email you send out. Make sure to be consistent with your colors and branding in your emails. Make sure that you're using a font that people can read. When they have received a few messages, your visitors will recognize your emails, and be happy to open them. For a business to be successful, it needs to be instantly recognizable, especially when it comes to e-mail marketing.<br><br>Take a look at the emails the competition are sending out. Obtain an email address specifically for this purpose, and join their lists, using it. Knowing what they are doing will help ensure your e-mail campaigns are better than their campaigns. If they are lacking in an area, you can try to make use of that within your campaign. Attempt to [http://Www.youtube.com/watch?v=5Kpt2ktXQPw develop] a better promotion than they are offering.<br><br>Branding is one thing that extends throughout your small business, even down to email marketing. That is why you must make time to build a great template which includes all of your sites primary features. 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Your customers, just like you, have busy lives and in all likelihood receive many emails every day. If you send out too many emails, they might not read them anymore and that is not good should you spent lots of time working on the messages.<br><br>If you're looking for a means to market your business, you might like to put your efforts into e-mail marketing. Use the strategies here to create an effective marketing with email plan and continuously seek ways on how to make the emails you signal to your customers and clients relevant. co-authored by Margarete I. Itzkowitz
 
==Energy requirements and comparisons==
The power per thrust required for a perfectly [[collimated]] output beam is 300 [[megawatt|MW]]/[[Newton (unit)|N]] (half this if it can be reflected off the craft); very high [[energy density]] power sources would be required to provide reasonable thrust without unreasonable weight. The specific impulse of a photonic rocket is harder to define, since the output has no (rest) mass and is not expended fuel; if we take the momentum per inertia of the photons, the specific impulse is just ''c'', which is impressive. However, considering the mass of the source of the photons, e.g., atoms undergoing [[nuclear fission]], brings the specific impulse down to 300&nbsp;km/s (''c''/1000) or less; considering the infrastructure for a reactor (some of which also scales with the amount of fuel) reduces the value further.  Finally, any energy loss not through radiation that is redirected precisely to aft but is instead conducted away by engine supports, radiated in some other direction, or lost via [[neutrino]]s or so will further degrade the efficiency. If we were to set 80% of the mass of the photon rocket = fissionable fuel, and recognizing that nuclear fission converts about 0.10% of the mass into energy: then if the photon rocket masses 300,000&nbsp;kg then 240,000&nbsp;kg of that is atomic fuel. Therefore the fissioning of all of the fuel will result in the loss of just 240&nbsp;kg of mass. Then  300,000/299,760&nbsp;kg = an ''m''<sub>i</sub>/''m''<sub>f</sub> of 1.0008. ''V''<sub>f</sub> = ln 1.008 × ''c'' where ''c'' = 300,000,000&nbsp;m/s.
''V''<sub>f</sub> then may be 240,096&nbsp;m/s which is 240&nbsp;km/s. The nuclear fission powered photon rocket may accelerate at a maximum of perhaps 1/10,000&nbsp;m/s² (0.1&nbsp;mm/s²) which is 10<sup>−5</sup>''g''. The velocity change would be at the rate of 3,000&nbsp;m/s per year of thrusting by the photon rocket.
 
If a photon rocket begins its journey in low earth orbit,  then one year of thrusting may be required to achieve an earth [[escape velocity]] of 11.2&nbsp;km/s if the vehicle is already in orbit at a velocity of 9,100&nbsp;m/s, and 400&nbsp;m/s additional velocity is obtained from the east to west rotation of the earth. The photon thrust will be sufficient to more than counterbalance the pull of the sun's gravity, allowing the photon rocket to maintain a heliocentric velocity of 30&nbsp;km/s in interplanetary space upon escaping the Earth's gravitational field. Eighty years of steady photonic thrusting would be then required to obtain a final velocity of 240&nbsp;km/s in this hypothetical case. At a 30&nbsp;km/s heliocentric velocity, the photon ship would recede a distance of 600,000,000 miles (1 Tm) from the Sun per year.
 
It is possible to obtain even higher specific impulse; that of some other photonic propulsion devices (e.g., [[solar sail]]s) is effectively infinite because no carried fuel is required.  Alternatively, such devices as [[ion thruster]]s, while having a notably lower specific impulse, give a much better thrust-to-power ratio; for photons, that ratio is <math>1/c</math>, whereas for slow particles (that is, nonrelativistic; even the output from typical ion thrusters counts) the ratio is <math>2/v</math>, which is much larger (since <math>v\ll c</math>).  (This is in a sense an unfair comparison, since the photons must be ''created'' and other particles are merely ''accelerated'', but nonetheless the impulses per carried mass and per applied energy&mdash;the practical quantities&mdash;are as given.)  The photonic rocket is thus wasteful when power and not mass is at a premium, or when enough mass can be saved through the use of a weaker power source that reaction mass can be included without penalty.
 
A laser could be used as a photon rocket engine, and would solve the reflection/collimation problem, but lasers are absolutely less efficient at converting energy into light than blackbody radiation is&mdash;though one should also note the benefits of lasers vs blackbody source, including unidirectional controllable beam and the mass and durability of the radiation source.
 
==Power sources==
Feasible current, or near-term fission reactor designs can generate up to 2.2&nbsp;kW per kilogram of reactor mass.{{Citation needed|date=July 2007}}  Without any payload, such a reactor could drive a photon rocket at nearly 10<sup>−4</sup> m/s² (10<sup>−5</sup>''g''; see [[g-force|''g''-force]]). This could perhaps provide [[interplanetary spaceflight|interplanetary]] spaceflight capability from Earth orbit.  [[Nuclear fusion]] reactors could also be used, perhaps providing somewhat higher power.
 
A design proposed in the 1950s by [[Eugen Sänger]] used [[positron]]-[[electron]] annihilation to produce [[gamma ray]]s. Sänger was unable to solve the problem of how to reflect, and collimate the gamma rays created by positron-electron annihilation; however, by shielding the reactions (or other [[annihilation]]s) and absorbing their energy, a similar blackbody propulsion system could be created. An [[antimatter]]-matter powered photon rocket would (disregarding the shielding) obtain the maximum ''c'' specific impulse; for this reason, an antimatter-matter annihilation powered photon rocket could potentially be used for [[interstellar travel|interstellar]] spaceflight.
 
==See also==
* [[Photon rocket]]
* [[Spacecraft propulsion]]
* [[Radioisotope rocket]]
 
==External links==
*[http://scitation.aip.org/getabs/servlet/GetabsServlet?prog=normal&id=APCPCS000552000001000957000001&idtype=cvips&gifs=yes Application of nuclear photon engines for deep-space exploration] by Andrey V. Gulevich, Eugeny A. Ivanov, Oleg F. Kukharchuk, Victor Ya. Poupko, and Anatoly V. Zrodnikov. ''AIP Conference Proceedings''
*"Interstellar rendezvous missions employing fission propulsion systems," Lenard, R.X., and Lipiniski, R.J., in ''Proceedings of the Space Technology Applications Int'l Forum'', 2000
*[http://adsabs.harvard.edu/cgi-bin/nph-bib_query?bibcode=2002AIPC..608..828G&amp;db_key=AST&amp;data_type=HTML&amp;format=&amp;high=43dbd51f4112230 On the conversion of infrared radiation from fission reactor-based photon engine into parallel beam], Gulevich, A. V.; Levchenko, V. E.; Loginov, N. I.; Kukharchuk, O. F.; Evtodiev, D. A.; Zrodnikov, A. V., in ''Proceedings of the Space Technology Applications Int'l Forum'', 2002
*[http://adsabs.harvard.edu/cgi-bin/nph-bib_query?bibcode=2002AIPC..608..596S&amp;db_key=AST&amp;data_type=HTML&amp;format=&amp;high=43dbd51f4130937 Long-life space reactor for photon propulsion], Sawada, T.; Endo, H.; Netchaev, A., in ''Proceedings of the Space Technology Applications Int'l Forum'', 2002
 
{{spacecraft propulsion}}
{{Nuclear propulsion}}
 
[[Category:Nuclear spacecraft propulsion]]

Latest revision as of 21:39, 6 December 2014



December 27, 2013 - Although all companies know the way important marketing is, they might not all use marketing tools effectively to increase profits. Email marketing is a simple approach to build your customer relationships without creating a huge investment. Continue reading to find out how you can send out effective emails.

Make sure your marketing with email campaign comes with an exit sign for people who want to opt out or unsubscribe. Emails do make time to delete if folks don't want them and so they may not appreciate needing to do that. Not only can being considered a spammer hurt your business, but you can also be blocked because of your provider.

A great way to grab an email recipient's attention is by making the e-mail personalized. Should they see your message like a form letter, it will likely be deleted and you'll be blocked. Using the first name with the recipient is easy, and you can even rise above that. You need to know where, when and why they enrolled. Utilize this information within your messages.

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In your email promotions, utilize the smallest amount of graphics as you possibly can. Some email readers block graphics automagically and if you are counting on graphics to obtain your message across, some readers won't obtain that message. As well, emails which can be heavily laden with graphics are often seen as junk or spam mail by email programs, meaning your email could land inside a junk folder quickly.

When researching email marketing, use as numerous resources as you possibly can. There is a helpful information available on the web about this. You can probably locate a number of classes or workshops where you live, so make sure to attend as much as you can.

Keep the style and format the identical for each email you send out. Make sure to be consistent with your colors and branding in your emails. Make sure that you're using a font that people can read. When they have received a few messages, your visitors will recognize your emails, and be happy to open them. For a business to be successful, it needs to be instantly recognizable, especially when it comes to e-mail marketing.

Take a look at the emails the competition are sending out. Obtain an email address specifically for this purpose, and join their lists, using it. Knowing what they are doing will help ensure your e-mail campaigns are better than their campaigns. If they are lacking in an area, you can try to make use of that within your campaign. Attempt to develop a better promotion than they are offering.

Branding is one thing that extends throughout your small business, even down to email marketing. That is why you must make time to build a great template which includes all of your sites primary features. This way, you can make the most of immediate familiarity for your audience.

Make sure your e-mail marketing stays in line with your company branding. Utilize the same color scheme and add your logo to each and every email you send. Your audience will recognize your logo and learn to trust it for those who have not old a good brand image.

Never use the cliche phrases in your marketing. Specifically steer clear of the "Buy now! the method that you go about it. A strategy such as this one is frequently perceived as being "spammy", meaning your consumers are going to unsubscribe. They understand you want to sell your product or service, so build a steady relationship with them first and provides it and yourself inside a professional manner. Your customers will appreciate happened doing this, and will also increase the likelihood of them purchasing one of your products.

Limit your marketing e-mail to only one each week. Your customers, just like you, have busy lives and in all likelihood receive many emails every day. If you send out too many emails, they might not read them anymore and that is not good should you spent lots of time working on the messages.

If you're looking for a means to market your business, you might like to put your efforts into e-mail marketing. Use the strategies here to create an effective marketing with email plan and continuously seek ways on how to make the emails you signal to your customers and clients relevant. co-authored by Margarete I. Itzkowitz

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