277 research outputs found
NUCLEIC-ACID BINDING DRUGS .2. PROFLAVINE FREE BASE
C13HIIN3.H20 , orthorhombic, Cmc21, a=
14.493 (8), b= 14.675 (8), c= 5.772 (5) A, Din= 1.29 (1),
De= 1.298 g cm -3 for Z=4. Equi-inclination Weissenberg
intensities, scanned with an automatic densitometer.
The structure, solved by direct methods, was
refined to R 0.0928 and Rw 0.0910 for 418 reflexions.
The ring system is slightly non-planar, and the crystal
structure is characterized by a lack of interplanar
stacking
9-CHLOROACRIDINE
C~3HsNC1, orthorhombic, P212~2 ~, a =
6.850 (3), b = 11.662 (5), c = 12.705 (5) A, O m =
1.40 (1), D c = 1.393 g cm -3 for Z = 4. Equi-inclination
Weissenberg intensities, scanned with an automatic
densitometer. The structure, solved by direct methods,
refined to R 0.0577 and R w 0.0649 for 1653
reflexions. The crystal structure is characterized by
partial stacking of the chromophores, these are slightly
non-planar
CRYSTAL-STRUCTURE OF AN ORTHORHOMBIC FORM OF ADENOSINE-5'-MONOPHOSPHATE
Adenosine-Y-phosphate monohydrate was crystallized in the orthorhombic space group P212121, with
a=22"997 (2), b=9.406 (1), c=6.599 (1)A,, Z=4. The structure was solved by direct methods and
refined to a final Rw of 0.0639 for 1320 significant reflexions measured on an automatic diffractometer.
The conformation of the molecule differs significantly from that previously reported for the monoclinic
monohydrate [Kraut & Jensen, Acta Cryst. (1963), 16, 79-88]. The sugar conformation, for example,
is here C(2)'-endo, and the glycosidic torsion angle has altered by almost 50 ┬░
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ENV-610: EFFECT OF NUTRIENTS ON METHANOTROPHIC OXIDATION ACTIVITY IN BATCH EXPERIMENTAL STUDIES
Methane biofiltration (MBF) has been proposed as an effective and cost efficient method for mitigating methane emissions from anthropogenic sources. Previous MBF studies have successfully demonstrated effective methane oxidation using compost, soil and biodegradable organic materials as the filter medium because they are a natural source of nutrients, organic matter content, and provide adequate space to support microbiological growth. However, these media types will inevitably decompose over time and lose their effectiveness. This study investigates the use of biologically stable media mixtures of lava rock and biochar in batch oxidation studies to determine their ability to support a methanotrophic bacterial population for the oxidation of methane. A screening experiment was performed using an unreplicated 23 factorial design to understand the influence of nutrient content, water holding capacity (WHC), and mixture ratios of lava rock and biochar, by volume, on the methane oxidation rate (MOR). Virtually no activity was observed when 3300 ppm of nitrogen were added to the batches. Methane oxidation activities were only observed when lower nutrient additions were made at 96 ppm of nitrogen with values reaching 2.2 - 2.5 mol/mLтИЩhr when the WHC was adjusted to 50% regardless of the media composition. Subsequent replicates performed at the lower nitrogen level additions and 30% WHC demonstrated similar MORs. Results demonstrate the supplementation of nutrients to a mixture of lava rock and biochar is possible in supporting a methanotrophic population and that lava rock can be used as a bulking agent
CRYSTAL AND MOLECULAR-STRUCTURE OF 2',3',5'-TRI-O-ACETYL-6-O-(MESITYLENESULPHONYL)GUANOSINE
The structure of a 6-O-mesitylenesulphonyl derivative of 2',3',5'-tri-O-acetylguanosine, C 24 H 29 N50 10 S, has
been determined by X-ray diffraction. Crystals are monoclinic, a = 26.370 (4), b = 8.200 (2), c =
17.991 (3) A, fl = 132.77 (4) o. The solution of the structure in space group C2 was not straightforward and is
described in detail. Refinement converged at R = 0.110 for 1102 observed reflections. The guanine base
displays some deviations from its usual geometry due to the loss of C(6)-O(6) double-bond character. The
ribose sugar is C(2')-endo puckered
The clam resources
Che estuaries and backwaters along the coasts of India have
immense clam resources which have been traditionally exploited
by the coastal people. The clams form the basis of subsistence
for the fishermen during seasons when sea fishing is at a low ebb
and clam fishing is a regular activity in many coastal regions of
Maharashtra, Goa, Karnataka and Kerala on the west coast.
Along the east coast, clam fishing is restricted to a few centres such
as the Kakinada Bay although, here and there, they are collected
for culinary purposes elsewhere. This is an activity where, besides
men and women, children participate. Clam marketing is highly
localised in centres of collection. Apart from introduction of
improved clam-scooping devices, the fishing method of hand-picking
has largely remained unchanged over the years
COMPARATIVE ANALYSIS OF STRUCTURAL PARAMETERS OBTAINED BY DIFFRACTOMETER AND SCANNING-DENSITOMETER MEASUREMENTS
The structure of cytosine monohydrate has been redetermined with reflexion data obtained from
automatic digital scanning of Weissenberg films. The previous determination with diffractometer data
[McClure & Craven, Acta Cryst. (1973), B29, 1234--1238] converged to an R of 0.037, with
average estimated standard deviations of 0"002 A and 0"15 ┬░ in derived bond lengths and angles. The
photographic data set converged to an R of 0-0672 with e.s.d.'s of 0-004--0-005 A and 0.3-0.4 ┬░. Normal
probability plots showed that the positional (and the derived geometric) parameters were very comparable;
the vibrational parameters were rather less so, some systematic error being apparent. The overall
conclusion from the study is that the two data sets have given essentially the same positional description
of the structure
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