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81.
G. Herrmann 《Holz als Roh- und Werkstoff》1979,37(11):435-437
The transportation problem at a timber drying plant had to be settled by means of a special truck. This truck, must be able to manipulate the timber piles in front of the kilns, in the socalled green-wood area, as well as after kiln drying, in the dry-wood-area. The special truck “Telemobil” itself and its applicability are discussed. 相似文献
82.
G. Herrmann 《Holz als Roh- und Werkstoff》1979,37(7):255-257
The installment of machinery according to a costumer's order is described. Both on working-days and on free weekends a kiln drying plant shall continuously furnish dried timber piled on rail carriers and transmit it to a buffer store. It is demonstrated that these requirements may be met with by installing a discontinuously working plant with automatic carrier return. 相似文献
83.
Hans-Joachim Nees Harald Keller Thomas Facklam Albert Herrmann Jochen Welsch Uwe Bergstrßer Heinrich Heydt Manfred Regitz 《Advanced Synthesis \u0026amp; Catalysis》1993,335(7):589-598
Diazo Compounds. 72. Diazoalkylphosphanes – Synthesis by Electrophilic Diazoalkane Substitution and Oxidative Addition Reactions at Phosphorus Electrophilic diazoalkane substitution of the diazomethyl compounds 1a,b with the chloro phosphanes 2a-o in the presence of lithium diethylamide yields the diazoalkyl phosphanes 3a-z . Oxidative addition of oxygen, sulfur and selenium at phosphorus leads into the series of oxo, thioxo and selenoxo phosphanes having diazoalkyl substituents ( 4a-d, 5a-m and 7a-d ). The silyl group of 5n,o is cleaved by chromatography on aluminium oxide to yield the (diazomethyl)phosphane sulfides 6a,b . 相似文献
84.
E. Fanghnel R. Herrmann J. Bierwisch H. Hartung U. Baumeister G. Maier H. P. Reisenauer 《Advanced Synthesis \u0026amp; Catalysis》1994,336(5):444-451
Alkylthiosubstituted Bis(benzene-1,2-dithiolato)zincates, Benzene-1,2-dithioles, and -1,2-dithiolates – Educts for Dibenzo[c,g](1,2,5,6)tetrathiocins, and Benzo[c](1,2,3)trithioles; Investigations on Benzodithietes and ortho-Dithiobenzochinones Using benzenehexathiolate 1 it is possible to synthesize alkylthio-substituted benzo-1,3-dithiole-2-thiones 2 , or -ones 3 and benzo-di(1,3-dithiole-2-thiones) 4 , or -ones 5 , resp., which were cleaved under basic conditions. The generated benzene-1,2-dithiolates 7 were isolated as benzene-dithiolato zincates 8 , benzene-1,2-dithioles 11 , and benzene-1-thiole-2-thiolates 10 . Dibenzo[c,g](1,2,5,6)-tetrathiocins 9 were synthesized by oxidation of 7 or 8 in good yields. For the per(methylthio)-substituted tetrathiocin 9a the twist conformation was proved by x-ray structure analysis. The tetrathiocin 9a was probably formed via the orthodithiobenzoquinone 13a . Photolysis of 3a at room temperature in solution led to 9a and tetrakis(methylthio)benzo[c] (1,2,3)trithiole 12a as the main product, which was also formed by irradiation of 9a . The trithioles 12 were formed from 8 by reaction with sulfur dichloride. 12a was investigated by x-ray structure analysis. ortho-Dithiobenzoquinone 13c can be claimed as an intermediate upon irradiation of benzo-1,3-dithiol-2-one 3c in an argon matrix at 10 K. Depending on the wavelength the equilibrium lies either on the side of dithiobenzoquinone 13c or benzodithiete 14c . The same is true for system 15/16 , which can be reached by flash vacuum pyrolysis of 3c . 相似文献
85.
Dr. J. Freiberg Dr. J. Herrmann Prof. Dr. H. Seeboth 《Advanced Synthesis \u0026amp; Catalysis》1982,324(4):563-568
On the Heterogeneous-Catalytic Oxidation and Ammoxidation of Isobutene. IV. Influence of n-Butene on the Heterogeneous-Catalytic Oxidation of Isobutene to Methacroleine The influence of n-butenes 2 on the oxidation of isobutenes 1 to methacroleine 3 has been investigated in presence of a catalyst containing Bi, Mo, P, Fe, Mg, Mn, Si and O. Addition of 2 to the gas mixture increase the selectivity and yield of 3 . This fact can be correlated by decrease of oxygen partial pressure in consequence of the dehydrogenation of 2 to butadiene 4 . 相似文献
86.
H J Herrmann 《Die Nahrung》1978,22(2):199-205
Under the influence of acidic agents, ceramic glazes and decorations for ceramics may release certain toxicants, especially lead and cadmium. Both elements are essential constituents of ceramic colours and glazes; their release to acidic foods is technologically unavoidable, but it may be minimized by the utilization of appropriate decoration agents and techniques. In most industrial countries, the release of toxicants from utensils is severely limited, the maximum permissible values and the methods of test and analysis being in part very different and not always in agreement with the demands and conditions of practice. The problems related to the release of toxicants from ceramic utensils are treated from the aspects of ceramics, test techniques, analytics, toxicology and food law, with special regard to the necessity for a well-balanced compromise between the justified hygienic demands of health protection and the actual technological possibilities. The endeavours of the ceramic industry of the GDF to produce ceramic utensils releasing as little toxicants as possible are outlined. 相似文献
87.
Tetrazole Compounds. 1. 1-Aryl-5-(2-dialkylamino-vinyl)-1H-tetrazoles from 3-Chloropropeniminium Salts 3-Chloropropeniminium salts 1 react with excess sodium azide in refluxing alcohols to give mainly 1-aryl-5-(2-dialkylamino-vinyl)-1H-tetrazoles 3 ; in minor quantities isomeric 5-aryl-1-(2-dialkylamino-vinyl)-1H-tetrazoles 4 are formed. The reaction involves splitting off N2 and C → N migration of the aryl and dialkylaminovinyl group, respectively. A cross-over experiment indicated that the rearrangement step proceeds intramolecularly. — The i.r., u.v., and n.m.r. spectroscopic data of the novel 1H-tetrazoles 3 as well as the u.v. spectra of some new starting products 1k—v are reported. 相似文献
88.
89.
90.
Occurrence and content of hydroxycinnamic and hydroxybenzoic acid compounds in foods 总被引:7,自引:0,他引:7
K Herrmann 《Critical reviews in food science and nutrition》1989,28(4):315-347
Phenolic acid compounds seem to be universally distributed in plants. They have been the subject of a great number of chemical, biological, agricultural, and medical studies. Hydroxycinnamic acid compounds occur most frequently as simple esters with hydroxy carboxylic acids or glucose, while the hydroxybenzoic acid compounds are present mainly in the form of glucosides. Furthermore, phenolic acids may occur in food plants as esters or glycosides conjugated with other natural compounds such as flavonoids, alcohols, hydroxyfatty acids, sterols, and glucosides. Also, hydroxycinnamic acid amides appear to be common constituents. The occurrence of the different natural phenolic acid compounds in foods is reviewed, and data of the content in fruit, vegetables, and spices are given. The distribution of the main phenolic acid compounds in food plants as well as their changes during development and maturation of fruits are considered. Furthermore, the hydroxycinnamic acids bound to cell wall polymers, the phenolic acid compounds in coffee, cereals, oil seed, and tree nuts, and the analysis of phenolic acid derivatives are reviewed. 相似文献