SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
SCHEDULE 13G
Under The Securities and Exchange Act of 1934
Amendment No. 1
DIONEX CORP.
(Name of Issuer)
Common
(Title of Class of Securities)
254546104
(CUSIP NUMBER)
The box below is checked if a fee is being paid
with this statement _
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CUSIP NO. 115 759 102
1) Name of Reporting Persons
S.S. or I.R.S. Identifica- PIONEERING MANAGEMENT
tion Nos. of Above Persons CORPORATION
2) Check the Appropriate Box (a)
of a Member of a Group
(See Instructions) (b) x
3) SEC Use Only
4) Citzenship of Place of State of Delaware
Organization
Number of (5) Sole Voting Power 746000
Shares
Beneficially (6) Shared Voting Power 0
Owned by Each
Reporting Per-
son With (7) Sole Dispositive 146000
Power
(8) Shared Dispositive 600000
Power
9) Aggregate Amount Beneficially 746000
Owned by Each Reporting Person
10) Check if the Aggregate Amount
in Row (9) Excludes Certain
Shares (See Instructions)
11) Percent of Class Represented 10.62
By Amount in Row 9.
12) Type of Reporting Person (See
Instructions IA
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Item 1(a) Name of Issuer:
DIONEX CORP.
Item 1(b) Address of Issuer's Principal Executive Officer
Barbara J. Posch
DIONEX CORP.
1228 Titan Way
Sunnyvale, CA 94088-3603
Item 2(a) Name of Person Filing
Pioneering Management Corporation
Item 2(b) Address of Principal Business Office:
60 State Street, Boston, MA 02114
Item 2(c) Citizenship:
State of Delaware - Pioneering Management Corporation
Item 2(d) Title of Class of Securities
Common
Item 2(e) CUSIP Number
254546104
Item 3 The person filing this statement pursuant to Tule 13-1(b) or
or 13d-2 is:
(a)Investment adviser registered under Section 203 of the
Investment Advisers Act of 1940.
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Item 4 Ownership.
(a) Amount Beneficially Owned: 746000
(b) Percent of Class: 10.62
(c) Number of shares as to which such person has:
(i) sole power to vote or to direct vote - 746000
(ii) shared power to vote or to direct vote - 0
(iii) sole power to dispose or to
direct disposition of - 146000
(iv) shared power to dispose or to direct
disposition of - 600000
Item 5 Ownership of Five Percent or Less of a Class.
Inapplicable.
Item 6 Ownership of More than Five Percent
on Behalf of Another Person.
Inapplicable.
Item 7 Identification and Classification of the Subsidiary Which
Acquired the Security Being Reported On By the Parent Holding
Company.
Inapplicable.
Item 8 Identification and Classification of Members of the Group.
Inapplicable.
Item 9 Notice of Dissolution of the Group.
Inapplicable.
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Item 10 Certification.
By signing below I certify that, to the best of my knowledge and
belief, the securities referred to above were acquired in the ordinary
course of business and were not acquired for the purpose of and do not
have the effect of changing or influencing the control of the issuer
of such securities and were not acquired in connection with or as a
participant in any transactions having such purposes or effect.
After reasonable inquiry and to the best of my knowledge and belief, I
certify that the information set forth in this statement is true,
complete and correct.
April 21, 1995
Date
/s/William H. Keough
Signature
William H. Keough, Senior Vice President,
Chief Financial Officer and Treasurer
Type Name and Tile
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