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1

Wypadkowość w małych firmach budowlanych

Dąbrowski A., Zamojski A.

Bezpieczeństwo Pracy : nauka i praktyka

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2011

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nr 11

6-9

PL

W artykule przedstawiono dane statystyczne dotyczące przyczyn wypadków w budownictwie. Szczególną uwagę zwrócono na polskie małe firmy budowlane przyczyniające się znacząco do wzrostu wypadkowości w tej branży. Omówiono czynniki mające największy wpływ na stan bhp w tych firmach. Opisano realia funkcjonowania małych firm budowlanych. Wzięto pod uwagę aspekty techniczne, organizacyjne, prawne i ekonomiczne ważne dla zapewnienia stanu bhp. Wskazano na istotną rolę generalnych wykonawców oraz kompetentnych instytucji w kształtowaniu bezpieczeństwa pracy w małych firmach budowlanych.

EN

In the paper statistical data concerning causes of accidents on construction site were presented. Special attention was turned onto polish small construction enterprises significantly influencing on accidents increase in this sector. Agents shaping osh state in these plants were discussed. The reality of small plants acting were described. Technical, organizational, legal and economical aspects were taken into account which are important for assurance of osh state. Essential function of general performers and competent institutions were pointed in the assurance of safety work of small construction enterprises.

2

Homologation of Protected Monosaccharides at the Terminal Position with Grignard C1 Reagents

Zamojski A.

Polish Journal of Chemistry

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2003

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Vol. 77 / nr 3

257-281

EN

The survey presents details of the recently introduced general method of homologation of monosaccharides. This method is based on chain-elongation of a protected monosaccharide from the terminal carbon atom. The terminal CH2OH group is oxidized to the aldehyde grouping and next reacted with an alkoxymethylmagnesium chloride (C1 Grignard) to form directly stereoisomeric homologues. The yields of the homologation products are high. Experiments aiming at improvement of the stereoselectivity of the reactions are described. The application of another C1 Grignard reagent, (phenyldimethylsilyl)methylmagnesium chloride, is presented. The advantages and disadvantages of the method are discussed. All syntheses connected with the important bacterial heptose, L-glycero-D-manno-heptose and its oligosaccharides are described.

3

Palladium Complexes in Carbohydrate Synthesis

Zamojski A.

Polish Journal of Chemistry

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2002

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Vol. 76 / nr 8

1053-1084

EN

The survey reports the results achieved in carbohydrate synthesis by application of organopalladium complexes. Most remarkable results have been noted in C-glycoside synthesis and in the chemistry of unsaturated sugars. In the majority of cases high regio- and stereoselectivity of transformations is observed. Many palladium catalysts with different organic ligands have been employed. The literature up to the end of 2001 is reviewed.

4

The reaction of (methylthio)acetyliron complex with pentose terminal aldehydes

Wiśniewski K., Zamojski A.

Polish Journal of Chemistry

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1998

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Vol. 72, nr 8

1937-1948

EN

The reaction between anion generated from (methylthio)acetyliron complex (1) and four stereoisomeric dialdo-1,4-furanoses was performed. Each aldehyde led to mixtures (6-8) of stereoisomeric aldols. Aldols were separated and their configaration was determined. Decomplexation of these products was studied with oxidative (NCS, Cl2, I2, CuCl2) and reducing (BH3xMe2S and NaBH4) reagents. Sugar derivatives were isolated and their structures were deduced.

5

Reaction of acetyliron anion with terminal halogeno-deoxysugars

Bartnicka E., Zamojski A.

Polish Journal of Chemistry

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1998

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Vol. 72, nr 4

688-693

EN

Reaction of the anion(2) generated from acetyliron complex (1) with methyl 5-bromo-5-deoxy-2,3-O-isopropylidene-beta-D-ribofuranoside (3) led to a Grob-type fragmentation of the furanoside to open-chain aldehyde (7) which, in situ, reated with 2 to form a mixture of stereoisomeric complexes 4. Decomplexation furnished methyl esters of 2,6,7-trideoxy-4,5-O-isopropylidene-heptonic acid of D-ribo and D-arabino configuration. Analogously, from methyl 2,3,4-tri-O-benzyl-6-bromo-6-deoxy-alpha-D- galactopyranoside (8) methyl 4,5,6-tri-O-benzyl-2,7,8-trideoxy-L-manno-oct-7-enoate (10) was obtained. Methyl 6-bromo (iodo)-6-deoxy-hexopyranoides 12-15 did not undergo Grob fragmentation in the presence of 2.