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81.
Moringa oleifera seeds, an environmental friendly and natural coagulant are reported for the pretreatment of palm oil mill effluent (POME). In coagulation-flocculation process, the M. oleifera seeds after oil extraction (MOAE) are an effective coagulant with the removal of 95% suspended solids and 52.2% reduction in the chemical oxygen demand (COD). The combination of MOAE with flocculant (NALCO 7751), the suspended solids removal increased to 99.3% and COD reduction was 52.5%. The coagulation-flocculation process at the temperature of 30 degrees C resulted in better suspended solids removal and COD reduction compared to the temperature of 40, 55 and 70 degrees C. The MOAE combined with flocculant (NALCO 7751) reduced the sludge volume index (SVI) to 210mL/g with higher recovery of dry mass of sludge (87.25%) and water (50.3%). 相似文献
82.
Kumar Akshi Bhatia M. P. S. Sangwan Saurabh Raj 《Multimedia Tools and Applications》2022,81(24):34615-34632
Multimedia Tools and Applications - Microblogs have become a customary news media source in recent times. But as synthetic text or ‘readfakes’ scale up the online disinformation... 相似文献
83.
84.
RG Stock K Chan M Terk JK Dewyngaert NN Stone P Dottino 《Canadian Metallurgical Quarterly》1997,37(4):819-825
The authors review the literature on intra-adenomatous pituitary apoplexy with special emphasis on pathophysiology, diagnosis and therapeutic approach. They present five cases, from a series of 86 patients with pituitary tumors, that developed this syndrome. The patients were diagnosed and followed by the Neurosurgery and Endocrinology Services of Hospital Universitario Clementino Fraga Filho, Universidade Federal do Rio de Janeiro. Diagnosis was confirmed by CT-Scan and MRI in all cases, and the treatment of choice was surgical. Conclusions point to the diagnostic difficulties and the urgency of treatment in this clinical setting. 相似文献
85.
Two improved strains of Pennisetum typhoideum (‘bajra’) were found to have a free lipid content of about 5.0% and bound lipid content of about 0.5%. In the non-polar fraction, sterol esters and hydrocarbons, triglycerides, free fatty acids, free sterols and partial glycerides were present with triglycerides as the principal constituents. Polar lipids were separated by two-dimensional thin-layer chromatography and lecithin was found to be the major component. Sterol-containing glycolipids (sterol glycosides and esterified sterol glycosides) were present in appreciable amounts. Phosphatidyl ethanolamine, phosphatidyl glycerol, phosphatidyl inositol, lysophosphatidyl ethanolamine, lysolecithin, phosphatidic acid, poly-glycerophosphatide, mono- and di-galactosyl glycerides and cerebrosides have also been tentatively identified. 相似文献
86.
87.
Ozkan M. Ozkan C.S. Kibar O. Wang M.M. Bhatia S. Esener S.C. 《IEEE engineering in medicine and biology magazine》2001,20(6):144-151
We apply basic electrophoretic motion to semiconductor materials engineering for development of the next level of heterogeneous integration technology. Furthermore, we demonstrate the utility of these tools in integration of inorganic devices with biological species in order to explore the utility of these tools in biotechnological applications.Electrical and optical addressing techniques are shown to allow for more rapid and parallel patterning of biological species and inorganic objects 相似文献
88.
The effect of interactions on the saturation remanence of assemblies of identical, uniaxially anisotropic, single-domain particles is calculated using a spatial-mean interaction field. The particle easy-axis directions are assumed known and given by a distribution function. The remanence is determined by finding the magnetization orientation functional of the particle easy-axis orientation which minimizes the total assembly energy. Curves of remanence versus interaction strength (assembly packing fraction) are shown for a) randomly oriented assemblies of spherical particles with uniaxial crystalline anisotropy only, b) randomly oriented assemblies of acicular particles with shape anisotropy, and c) oriented assemblies of acicular particles with 6:1 aspect ratio. Disregarding external sample-shape demagnetization effects, this model always yields increased remanences due to interactions. A criterion is given which predicts when external shape effects are capable of dominating the net interaction field to yield a reduction in remanence. The applicability of these results and extensions of the theory are discussed in relation to particle assemblies in magnetic tape and high coercivity CoNiP films. 相似文献
89.
IS Efimova A Salminen P Pohjanjoki J Lapinniemi NN Magretova BS Cooperman A Goldman R Lahti AA Baykov 《Canadian Metallurgical Quarterly》1999,274(6):3294-3299
Recent crystallographic studies on Escherichia coli inorganic pyrophosphatase (E-PPase) have identified three Mg2+ ions/enzyme hexamer in water-filled cavities formed by Asn24, Ala25, and Asp26 at the trimer-trimer interface (Kankare, J., Salminen, T., Lahti, R., Cooperman, B., Baykov, A. A., and Goldman, A. (1996) Biochemistry 35, 4670-4677). Here we show that D26S and D26N substitutions decrease the stoichiometry of tight Mg2+ binding to E-PPase by approximately 0.5 mol/mol monomer and increase hexamer stability in acidic medium. Mg2+ markedly decelerates the dissociation of enzyme hexamer into trimers at pH 5.0 and accelerates hexamer formation from trimers at pH 7.2 with wild type E-PPase and the N24D variant, in contrast to the D26S and D26N variants, when little or no effect is seen. The catalytic parameters describing the dependences of enzyme activity on substrate and Mg2+ concentrations are of the same magnitude for wild type E-PPase and the three variants. The affinity of the intertrimer site for Mg2+ at pH 7.2 is intermediate between those of two Mg2+ binding sites found in the E-PPase active site. It is concluded that the metal ion binding site found at the trimer-trimer interface of E-PPase is a high affinity site whose occupancy by Mg2+ greatly stabilizes the enzyme hexamer but has little effect on catalysis. 相似文献
90.
NN Ninkina EM Privalova LG Pin?n AM Davies VL Buchman 《Canadian Metallurgical Quarterly》1999,246(2):308-311
Synucleins constitute a group of unique, evolutionarily conserved proteins that are expressed predominantly in neurons of the central and peripheral nervous system. Although the normal cellular functions of synucleins are not clear, these proteins have been implicated in various neurodegenerative conditions in humans. We found that persyn, a recently characterized member of the synuclein family, is expressed not only in the nervous system but also in the stratum granulosum of the epidermis of neonatal and adult mice. This finding together with our recent observations that persyn influences neurofilament network integrity in sensory neurons raises the possibility that persyn in skin could be involved in modulation of the keratin network. 相似文献