Background The vast majority of research into solid-state polymer electrolytes for low-temperature (o200 1C) fuel cells has focused on proton-exchange membrane (PEM) fuel cells (PEMFCs). Recently, there has been interest in the application of the analogous anion-exchange membranes (AEMs), in alkaline forms, in low-temperature fuel cells (Figure 1).
The Encyclopedia of Soils in the Environment is a vitally important scientific publication and an equally
important contribution to global public policy. The Encyclopedia brings together a remarkable range of
cutting-edge scientific knowledge on all aspects of soil science, as well as the links of soils and soil science to
environmental management, food production, biodiversity, climate change, and many other areas of significant
Correction of blood lipid abnormalities offers scope for a major impact on cardiovascular disease. Drugs play a significant role and have a variety of modes of action. Dietary and lifestyle adjustment are components of overall risk prevention.
The bleached pulps were screened prior to sheet preparation. All analyses were
performed according to ISO and SCAN standards, except for the carbohydrate
analysis of straw which was done by high-performance anion-exchange
chromatography (HPAEC). The ashing was conducted at 550°C for 12 h.
The mechanically refined pulp after hot water treatment was fractioned with a
Bauer McNett apparatus. The paper technical properties were determined from
the combined 100 and 200 mesh fractions.
Urine, amniotic fluid and ascitic fluid samples of galactosialidosis patients
were analyzed and structurally characterized for free oligosaccharides using
capillary high-performance anion-exchange chromatography with pulsed
amperometric detection and online mass spectrometry. In addition to the
expected endo-b-N-acetylglucosaminidase-cleaved products of complex-type
sialylated N-glycans, O-sulfated oligosaccharide moieties were detected.
Two soluble enzymes (FerA and FerB) catalyzing the
reduction of a number of iron(III) complexes by NADH,
were purified to near homogeneity from the aerobically
grown iron-limited culture ofParacoccus denitrificansusing
a combination of anion-exchange chromatography (Seph-arose Q), chromatofocusing (Mono P), and gel permeation
chromatography (Superose 12). FerA is a monomer with
a molecular mass of 19 kDa, whereas FerB exhibited a
molecular mass of about 55 kDa and consists of probably
two identical subunits. ...
Bacillus cereusisolated from the larvae of Myrmeleon bore
was found to secrete proteins that paralyze and kill German
cockroaches, Blattela germanica, when injected. One of
these active proteins was purified from the culture broth
ofB.cereususing anion-exchange and gel-filtration chro-matography. The purified toxin, with a molecular mass of
34 kDa, was identified as sphingomyelinase C (EC22.214.171.124)
on the basis of its N-terminal and internal amino-acid
sequences. A recombinant sphingomyelinase C expressed in
Escherichia coliwas as potent as the native protein in killing
From the lipopolysaccharide of the deep rough mutant I-69 Rd–/b+ of Haemophilus inﬂuenzae two oligosaccharides were obtained after de-O-acylation and separation by high-performance anion exchange chromatography. Their chemical structures were determined by one- and two-dimensional 1H-, 13C- and 31P-NMR spectroscopy as aKdo-4P-(2 ﬁ 6)-bGlcN-4P-(1 ﬁ 6)-aGlcN-1P and aKdo-5P-(2 ﬁ 6)-bGlcN-4P-(1 ﬁ 6)-aGlcN-1P.
The synthesis of 10 new phosphoenolpyruvate (PEP) analogues with modiﬁcations in the phosphate and the carboxylate function is described. Included are two potential irreversible inhibitors of PEP-utilizing enzymes. One incorporates a reactive chloromethylphosphonate function replacing the phosphate group of PEP. The second contains a chloromethyl group substituting for the carboxylate function of PEP. An improved procedure for the preparation of the known (Z)- and (E)-3-chloro-PEP is also given.
Due to the high toxicity of arsenic and the poison effects to human being, identification and quantification of individual arsenic forms are important to appropriately measure the arsenic toxicity, environmental impact and health risk related to arsenic exposure. Arsenic species were quantified by HPLC-UV-HG-AAS. The separation was performed on an anion exchange Hamilton PRP-X100 (250 mm× 4,1 mm i.d.× 10 µm) column by using mobile phase A: 12 mmol/l KH2PO4- K2HPO4; pH = 6.5 and B: 24 mmol/l KH2PO4-K2HPO4; pH = 6.
The procedure for determination of 238 U, 234 U, 232 Th, 230 Th and 228 Th nuclides by alpha spectroscopy was developed. Nuclides of uranium (U) and thorium (Th) were separated from the soil samples by chromatographic method. In the medium of 8 M nitric acid, U(VI) and Th(IV) were adsorbed on the Dowex 1 anion resin column. However, U(VI) was eluted from column by increasing the used volume of 8 M nitric acid. Th(IV) was eluted from the column with 50 ml HCl 9 M.
Cellulosomes produced byClostridium cellulolyticumgrown on cellulose
were purified and separated using anion-exchange chromatography.
SDS⁄PAGE analysis of six fractions showed variations in their celluloso-mal protein composition. Hydrolytic activity on carboxymethyl cellulose,
xylan, crystalline cellulose and hatched straw differed from one fraction to
Trypanosoma cruzi, the parasitic protozoan that causes Chagas disease,
contains a major cysteine proteinase, cruzipain. This lysosomal enzyme
bears an unusual C-terminal extension that contains a number of post-translational modifications, and most antibodies in natural and experimen-tal infections are directed against it. In this report we took advantage of
UV-MALDI-TOF mass spectrometry in conjunction with peptide N-gly-cosidase F deglycosylation and high performance anion exchange chroma-tography analysis to address the structure of the N-linked oligosaccharides
present in this domain. ...
Lipopolysaccharide (LPS) ofEscherichia colistrain2513 (R4
core-type) yielded after alkaline deacylation one major
oligosaccharide by high-performance anion-exchange chro-matography (HPAEC) which had a molecular mass of
2486.59 Da as determined by electrospray ionization mass
spectrometry. This was in accordance with the calculated
molecular mass of a tetraphosphorylated dodecasaccharide
of the composition shown below.
This paper deals with the purification and the partial char-acterization of glutathione S-transferase (GST) isoforms
from the clam Ruditapes decussatus. For the first step of
purification, two affinity columns, reduced glutathione
(GSH)–agarose and S-hexyl GSH–agarose, were mounted
in series. Four affinity fractionswere thus recovered. Further
purification was performed using anion exchange chroma-tography. Seven fractions,whichpresent aGSTactivitywith
1-chloro-2,4-dinitrobenzene (CDNB) as substrate, were
collected and analyzed by RP-HPLC....
Ion Exchange Processes
Ion trao đổi, trao đổi giữa các ion trong dung dịch và ion khác trong lớp ranh giới giữa các giải pháp và một bề mặt tích điện (Bảng thuật ngữ của Điều khoản Khoa học Đất, 1997), thực sự đã là một trong những dấu hiệu hóa học của đất. Kể từ khi các nghiên cứu tiên phong của J. Thomas Way vào giữa thế kỷ 19 (Way, 1850), nhiều nghiên cứu quan trọng đã xảy ra trên các khía cạnh khác nhau của cả hai cation và trao đổi anion trong đất.