Document:

Exhibit 10.68

                                 PROMISSORY NOTE

$76,637.00                                                February 24, 2004
                                                          Belmont, Massachusetts

         FOR VALUE RECEIVED, KRONOS ADVANCED TECHNOLOGIES, INC., a Nevada
Corporation (the "Borrower"), hereby promises to pay to the order of Richard A.
Papworth (the "Lender"), at 14523 Westlake Drive, Lake Oswego, Oregon 97035, or
such other place or places as he may designate, in lawful money of the United
States of America, the principal sum of Seventy-Six Thousand Six Hundred
Thirty-Seven Dollars (US$76,637.00), together with accrued interest on the
unpaid principal balance hereof from the date of this Note.

         Except as set forth below upon the occurrence of an Event of Default
(as defined below), interest shall not accrue on this Note. The entire principal
amount and all accrued interest shall be due and payable by the Borrower on June
30, 2004. Upon the occurrence of an Event of Default by the Borrower, all sums
outstanding under this Note shall thereupon immediately bear interest at the
rate of seventeen percent (17%) per annum. Any failure to make any payment due
under this Note within fifteen (15) days of when such payment is due shall be an
event of default ("Event of Default"). The Borrower does not intend or expect to
pay, nor does the Lender intend or expect to charge, collect or accept, any
interest greater than the highest legal rate of interest which may be charged
under any applicable law. Should the acceleration hereof or any charges made
hereunder result in the computation or earning of interest in excess of such
legal rate, any and all such excess shall be and the same is hereby waived by
the Lender, and any such excess shall be credited by the Lender to the principal
balance hereof.

         If any amount hereunder is payable on a day which is a Saturday,
Sunday, legal holiday or a day on which banking institutions in New York, New
York, are authorized or required by law or by local proclamation to close, the
due date thereof shall be extended to the next succeeding business day and
interest thereon shall accrue during the period of such extension at the rate
provided herein.

         At the option of the Lender, all sums advanced hereunder together with
accrued interest thereon shall become immediately due and payable, without
notice or demand, upon the commencement of any proceedings under any bankruptcy
laws of any jurisdiction or under any insolvency, reorganization, receivership,
readjustment of debt, dissolution or liquidation law or statute of any
jurisdiction now or hereafter in effect (whether in law or equity) is filed by
or against the Borrower or for all or any part of its property.

         No delay or omission on the part of the Lender in the exercise of any
rights hereunder shall operate as a waiver of such right or of any other right
under this Note. A waiver by the Lender of any right or remedy conferred to it
hereunder on any one occasion shall not be construed as a bar to, or waiver of,
any such right or remedy as to any future occasion.

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         Principal may be prepaid in whole or in part at any time prior to the
maturity of this Note. There is no prepayment fee or penalty.

         This Note shall be construed and enforced according to the laws of the
State of Nevada, excluding all principles of choice of laws, conflict of laws or
comity.

         The terms of this Note may not be changed orally. This Note shall be
binding on the successors and assigns of the Borrower.

         THE BORROWER HEREBY KNOWINGLY, VOLUNTARILY AND INTENTIONALLY WAIVES THE
RIGHT WHICH IT MAY HAVE TO A TRIAL BY JURY OF ANY CLAIM, DEMAND, ACTION OR CAUSE
OF ACTION BASED HEREON, OR ARISING OUT OF, UNDER OR IN ANY WAY CONNECTED WITH
THE DEALINGS BETWEEN THE LENDER AND THE BORROWER, THIS NOTE, OR ANY DOCUMENTS
EXECUTED IN CONNECTION HEREWITH, OR THE FINANCING CONTEMPLATED HEREBY, OR ANY
COURSE OF CONDUCT, COURSE OF DEALING, STATEMENTS (WHETHER ORAL OR WRITTEN) OR
ACTIONS OF ANY PARTY HERETO OR THERETO IN EACH CASE WHETHER NOW EXISTING OR
HEREAFTER ARISING, AND WHETHER IN CONTRACT, TORT, EQUITY OR OTHERWISE. THIS
PROVISION IS A MATERIAL INDUCEMENT FOR THE LENDER EXTENDING THE LOAN EVIDENCED
BY THIS NOTE.

                                           KRONOS ADVANCED TECHNOLOGIES, INC.

                                           By:
                                         Name:    Daniel R. Dwight
                                        Title:    President and CEOExhibit 10.69

                                 PROMISSORY NOTE

$363,139.00                                               Belmont, MA
March 31, 2004                                            Due: December 31, 2006

         For value received, the undersigned, Kronos Advanced Technologies,
Inc., a Nevada corporation, (the "Company") and Kronos Air Technologies, Inc.
("Kronos Air"), a Nevada corporation, (the Company and Kronos Air Technologies,
Inc. are hereinafter referred to jointly as "Borrowers") jointly and severally
promise to pay to the order of Daniel R. Dwight (hereinafter, "Lender") at
Lender's offices located at 464 Common Street, Suite 301, Belmont, MA 02478 or
at such other place as the holder of this Promissory Note may from time to time
designate the principal sum of three hundred forty-three thousand three hundred
eighty-nine Dollars ($363,139.00), together with interest thereon at the rate
hereinafter specified, and any and all other sums which may be due and owing to
the holder of this Promissory Note in accordance with the following terms:

         1.    Repayment. Commencing April 1, 2004 and provided that the
Borrowers have a combined minimum cash balance of two hundred thousand dollars
($200,000), the Borrowers shall repay the lender the last day of each month in
cash six thousand seven hundred and eighteen dollars ($6,718). In the event that
the Borrowers' combined cash balance is less than $200,000, then the $6,718
would be deferred to the next month and added to the payment for the next month
subject to the same minimum cash requirements. Commencing upon the earliest of
the following the Borrowers shall repay the Lender in full in cash for the
outstanding principal and accrued and unpaid interest:

a)            In the event of a "Change of Control." For purposes of this Note,
              a "Change in Control" shall have the same meaning as set forth in
              the Employment Agreement between Lender and the Borrower;

b)            In the event of an "Event of Default" (as defined below);

c)            In the event that the Borrowers secure cumulative debt or equity
              financing from a source other than Fusion Capital in the amount of
              $5,000,000 or more; in the event that the Borrowers secure
              cumulative debt or equity financing from a source other than
              Fusion Capital between $1,000,000 and $5,000,000, then an amount
              equal to seven percent (7%) of the net proceeds not to exceed the
              total amount owed under this Promissory Note would be additionally
              due and owing under this Promissory Note;

d)            In the event the Lender is no longer employed by the Borrowers,
              this Promissory Note is payable as follows:

<PAGE>

i.            if the Lender's employment is terminated by the Borrowers for
              "Cause" as defined in the Lender's Employment Agreement with the
              Borrowers, this Promissory Note will be due and payable in twelve
              (12) equal monthly installments commencing thirty (30) days after
              the date of termination;

ii.           if the Lender's employment with the Borrowers is terminated for
              any reason other than "Cause" as defined in the Lender's
              Employment Agreement with the Borrowers, then this Promissory Note
              will be due and payable in six (6) equal monthly installments
              commencing thirty (30) days after the date of termination;

e)            In no event shall the outstanding principal and all accrued
              interest due under this Promissory Note be repaid to the Lender
              later than December 31, 2006.

         2.    Interest Rate.  Interest shall accrue at a rate of one percent
(1%) per month simple interest.

         3. Calculation of Interest. Interest on this Note shall be calculated
on the basis of a thirty (30) day per month factor applied to the actual days on
which there exists an unpaid principal balance due under this Promissory Note.

         4. Application of Payments. All payments made hereunder shall be
applied first to late penalties or other sums owing the holder, then to accrued
interest, and last to repayment of the principal amount of this Promissory Note.

         5. Prepayment. Borrowers may prepay this Promissory Note in whole or in
part at any time or from time to time without penalty or additional interest,
provided that payments are applied as provided in Section 4 above.

         6. Default and Remedies. Any failure to make any payment due under this
Promissory Note when due or upon the failure to comply with any other terms and
provisions of this Promissory Note which is not cured within thirty (30) days
after receipt of written notice from the Lender shall be an event of default
under this Promissory Note (an "Event of Default") and shall entitle Lender to
all of the rights and remedies specified herein or otherwise available under
applicable law, without any further notice, any further right to cure, or
obligation to make demand for payment. Upon an Event of Default, the entire
unpaid principal balance of this Promissory Note, together with all accrued but
unpaid interest and other sums due hereunder, shall immediately become due and
payable in full, in cash, and Lender shall have the right to bring suit for such
amount and to exercise any other remedies available.

         7. Attorney's Fees. The prevailing party in any litigation shall be
entitled to recover all costs and expenses (including court costs and reasonable
attorneys' fees).

                                      -2-

<PAGE>

         8. Extensions or Modifications. All parties to this Promissory Note,
whether maker, endorsor or guarantor, agree that the maturity of this Promissory
Note or any payment due hereunder may be extended at any time or from time to
time, this Promissory Note may be modified, and any Event of Default hereunder
may be waived without releasing, discharging or affecting the liability of
Borrowers or any other party not specifically released.

         9. Venue. Borrowers agree that venue shall be proper in any state court
in the Commonwealth of Massachusetts in any action or proceeding brought to
construe, interpret or enforce this Promissory Note or any related document.
Borrowers waive the benefit of any and every statute, ordinance or rule of court
which may be lawfully waived conferring upon Borrowers any right or privilege,
stay of execution, or supplementary proceeding or other relief from the
immediate enforcement of a judgment or related proceedings on a judgment. The
Borrowers waive the benefit of any exemption laws. The authority granted herein
shall not be exhausted by any one or more exercises or be extinguished by any
judgment entered, and may be exercised on one or more occasions and in one or
more jurisdictions.

          10. Waiver of Defenses; Setoff. The Borrowers agree that neither the
Lender nor any subsequent holder of this Promissory Note shall be subject to any
claims, defenses or setoffs which Borrowers may have against the Lender or any
prior holder, all of which are waived as to the Lender and any subsequent
holders, and all subsequent holders shall have the rights of a holder in due
course with respect to Borrowers even though the subsequent holder might not
qualify under applicable law absent this paragraph as a holder in due course.

          11. Waiver of Protest. Borrowers and all parties to this Promissory
Note hereby waive presentment, protest and demand and notice of protest, demand,
dishonor and nonpayment of this Promissory Note.

          12. Commercial Loan Transaction. Borrowers warrant and agree that this
Promissory Note is the result of a commercial loan transaction.

          13. No Waiver. The delay or failure of any holder to exercise its
rights hereunder shall not be deemed a waiver thereof. No waiver of any rights
of holder shall be effective unless in writing and signed by the holder, and any
waiver of any right shall not apply to any other right or to such right in any
subsequent event or circumstance not specifically included in such waiver.

         14. Notices. Any notices required hereunder shall be deemed properly
given if delivered in person or if mailed by registered or certified mail,
postage prepaid, return receipt requested to the parties at the following
addresses:

         15. Headings. The section and subsection headings in this Promissory
Note are inserted for convenience only and shall not affect in any way the
meaning or interpretation of this Promissory Note.

                                      -3-

<PAGE>

   If to Kronos Advanced Technologies, Inc. or Kronos Air Technologies, Inc. to:

                  Mr. Rich Tusing
                  Kronos Advanced Technologies, Inc
                  464 Common Street, Suite 301
                  Belmont, Massachusetts 02478

                  with a copy to:

                  Clayton E. Parker, Esq.
                  Kirkpatrick & Lockhart LLP
                  201 South Biscayne Boulevard, Suite 2000
                  Miami, Florida  33131

   If to Lender:

                  Mr. Daniel R. Dwight
                  Kronos Advanced Technologies, Inc.
                  464 Common Street, Suite 301
                  Belmont, Massachusetts 02478

or to such other address as any party may hereafter give notice of to the other.

         16. Choice of Law. This Promissory Note shall be deemed to be made in
the Commonwealth of Massachusetts and shall be governed, construed and enforced
in strict accordance with the laws of the Commonwealth of Massachusetts, without
reference to principles of conflict of laws.

                        SIGNATURES ON THE FOLLOWING PAGE

                                      -4-

<PAGE>

         IN WITNESS WHEREOF, Borrowers have caused this Promissory Note to be
executed on their behalf by their respective duly authorized officers and their
respective corporate seals to be affixed and attested by their respective
Secretaries as of the day and year first above written.

ATTEST:                                      KRONOS ADVANCED TECHNOLOGIES, INC.

                                       By:                                [SEAL]
------------------------------------      --------------------------------
Secretary                              Name: Spencer I. Browne
                                      Title: Director and Member Board of
                                             Directors'
                                             Compensation Committee

ATTEST:                                      KRONOS AIR TECHNOLOGIES INC.

                                       By:                                [SEAL]
------------------------------------      --------------------------------
Secretary                              Name: Richard A. Papworth
                                      Title: Director Finance & Accounting.

                                      -5-

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