Patents - Costs and accumulated amortization of patents (Details) (USD $)	12 Months Ended
Jul. 31, 2013	Jul. 31, 2012
Accounting Policies [Abstract]
Patents	$ 5,657,455	$ 5,587,790
Less: Accumulated Amortization	3,338,039	2,953,332
Patents, Net	$ 2,319,416	$ 2,634,458
Weighted Average Life	8 years 7 months 6 days	9 years 4 months 24 days

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Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 350

-SubTopic 30

-Section 50

-Paragraph 2

-Subparagraph (a)(1)

-URI http://asc.fasb.org/extlink&oid=26713463&loc=d3e16323-109275

+ Details

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- Definition

Amount before amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

+ Details

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- Definition

Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ References

+ Details

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- Definition

Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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