APAKAH MAKSUD LAEVOROTATION dalam CORSICA?
Dextrorotation and levorotation
Dextrorotation dan levorotation merujuk kepada sifat-sifat cahaya polarisasi pesawat berputar. Sekiranya cahaya berputar mengikut arah jam kerana ia menghampiri pemerhati, ini dikenali sebagai dextrorotation, cahaya dengan putaran ke kanan. Sekiranya cahaya berputar sejam kerana ia menghampiri pemerhati, maka cahaya mempamerkan levorotation, putaran ke kiri. Kompaun dengan dextrorotation dipanggil dextrorotatory atau dextrorotary, manakala sebatian dengan levorotation dipanggil levorotatory atau levorotary. Sebatian dengan sifat-sifat ini dikatakan mempunyai aktiviti optik dan terdiri daripada molekul kiral. Jika molekul kiral adalah dextrorotary, enantiomernya akan menjadi levorotary, dan sebaliknya. Sebenarnya, enantiomer akan memutarkan cahaya polarisasi pesawat dengan jumlah darjah yang sama, tetapi dalam arah yang bertentangan. Selain daripada pengukuran langsung bagi putaran optik sampel sebenar, hanya boleh dilakukan untuk menentukan sama ada molekul kiral yang diberi akan levorotatory atau dextrorotatory, secara langsung dari konfigurasi mutlaknya, melalui pemodelan komputer terperinci. Maksudnya, kedua-dua stereocenters "R" dan "S" mempunyai keupayaan untuk menjadi dextrorotatory atau levorotatory.
Definisi laevorotation dalam kamus Corsica
Takrif pencerapan dalam kamus adalah putaran ke kiri. Takrifan lain mengenai pencerobohan adalah putaran sejam dari satah polarisasi lampu terpolarisasi pesawat sebagai hasil daripada laluannya melalui kristal, cecair, atau penyelesaian.
CORSICA BUKU YANG BERKAIT DENGAN «LAEVOROTATION»
Ketahui penggunaan
laevorotation dalam pilihan bibliografi berikut. Buku yang berkait dengan
laevorotation dan ekstrak ringkas dari yang sama untuk menyediakan konteks penggunaannya dalam kesusasteraan Corsica.
1
The Journal of Physiology
This laevorotation reaches a maximum with the formation of a precipitate which is
equally distributed throughout the fluid. With the settling of the precipitate the
laevorotation gradually diminished and it was during this stage that we were
forced ...
2
Annual Report on Essential Oils, Aromatic Chemicals and ...
The feeble laevorotation of the oils 3 to 6 is worthy of note. As the distillation was
carried out under our constant supervision, and special attention was paid to the
fact that no lavender was present among the spike blossoms, a slight ...
Schimmel & Co, Schimmel & Co. Aktiengesellschaft, Miltitz bei Leipzig,
1908
3
The American Perfumer and Essential Oil Review
From an examination of all these figures it appears that the dextrorotatory
samples would usually be adjudged better than samples which had much
laevorotation: for the presence of much stalk in the herb appears to be to some
extent the ...
Rhamnose, originally dextrorotatory, becomes laevorotatory on oxidation, and
the rotation is practically constant after 2 gram-atoms of oxygen have been added
. This laevorotation appears to be due to the presence of a laevorotatory keto-
acid ...
Chemical Society (Great Britain),
1905
5
A Textbook Of Organic Chemistry, 3E
In the D-series of sugars having laevorotation, it is the p-anomer which has a
higher laevorotation. Thus fructose having a specific rotation of -20° will be a-D (-
) fructose and the other one with a specific rotation of -133° will be the P-anomer.
Asha Viswas, Ks Tewari,
2009
6
A physico-chemical approach to the denaturation of proteins
Probably as a consequence of the presence of two additional aspartic acid
residues in j8-lactoglobulin A, its laevorotation drops at pH 3-8, then decreases to
pH 4-1, and finally increases to pH 5-0; the curve afterwards parallels that of ...
Maurice Joly, M. Joly (biophysicist.),
1965
7
Archives Internationales de Physiologie Et de Biochimie
The laevorotation of /?A and /SB decreases slightly on addition of the
amphiphiles up to a molar ratio of 2//Mactoglobulin, the more the longer the
carbon chain. A marked, up to about twofold, laevorotation increase is observed
at ratios above ...
But the laevorotation of fructose is much more in magnitude than the
dextrorotation of glucose, with the result that solution of sucrose exhibits
laevorotation. As inversion in optical rotation takes place, it is called invert sugar.
Sucrose does not ...
9
Comprehensive Natural Products Chemistry
The Amphimedon sponge also contains several manzamine related alkaloids
with both dextrorotation and laevorotation. The minor enantiomer of
keramaphidin B ((−)(662)) is considered to possess the same configuration as
most of the ...
Derek Barton, O. Meth-Cohn,
1999
10
Nutrition and Biochemistry for Nurses
The resultant product of hydrolysis shows laevorotation. This change from
dextrorotation to laevorotation is called inversion. Therefore, sucrose is called
invert sugar. The net result is laevorotatory resulting in change of rotation from
positive ...