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21.
Single-metal high-temperature solid sorbents for syngas cleaning using Mn, Ca, Fe, Cu, or Mo supported on γ-Al2O3 were synthesized, characterized, and tested in a fixed-bed reactor. H2S and SO2 concentrations in the gas after treatment at T = 400 to 700 °C were compared with thermodynamic calculations. The Mn-based sorbent showed the best ability to achieve a low sulfur residual in the gas, especially at temperatures above 600 °C. Sorbents with Fe, Cu, and Mo gave SO2 formation in the initial phase, but this could be avoided by a pre-reduction treatment of the sorbent material. 相似文献
22.
Climate change impacts on natural resources and communities: A geospatial approach for management 下载免费PDF全文
Adikanda Ojha Ajit Kumar Pattnaik Jajnaseni Rout 《Lakes & Reservoirs: Research and Management》2018,23(1):34-42
Climate change causes environmental depletion, with threats to the global economy. The health and productivity of ecosystems underpin agriculture, with stable ecosystems being the foundation for economic livelihoods and food security. This study proposes adaptation measures, using geospatial technology, for conserving natural resources and improving livelihoods of the local community from climate change scenarios. Planning, policy decisions and resultant programmes are required for natural resource management, which must be based on broad citizen participation and the engagement of rural communities. The suggested adaptation measures will help the planning system to regulate development of natural resources and the socio‐economic environment. The major natural resources in the environment are land and water, both of which can be severely degraded by human interventions, as well as climate change. Various thematic maps are prepared with the use of geospatial technology, in order to be helpful for site‐suitability analysis directed to the preparation of land and water management action plans for socio‐economic development. The study area is a micro‐watershed of the catchment of Ansupa Lake in the Cuttack District of Odisha, India. To reduce climate change impacts on natural resources and economic livelihoods, some adaptation measures have been proposed (e.g., 68.9 ha for afforestation.; 13.94 ha for gap plantations and agro‐horticulture; 389.62 ha for farm ponds and renovation of existing ponds for pisciculture and duckery activities, etc.; 11.33 ha for land management, along with five bore wells, eight dug wells, 51 LBS/check dams, and four WHSs, etc., for water management for sustainable use). 相似文献
23.
A complex of the chi and psi proteins is required to confer resistance to high levels of glutamate on the DNA polymerase III holoenzyme-catalyzed reaction (Olson, M., Dallmann, H. G., and McHenry, C. (1995) J. Biol. Chem. 270, 29570-29577). We demonstrate that this salt resistance also requires templates to be coated with the Escherichia coli single-stranded DNA-binding protein (SSB). We show that this is the result of a direct chipsi-SSB interaction that is strengthened approximately 1000-fold when SSB is bound to DNA. On model oligonucleotide templates, DNA polymerase III core is inhibited by SSB. We show that the minimal polymerase assembly that will synthesize DNA on SSB-coated templates is polymerase III-tau-psi chi. gamma, the alternative product of the dnaX gene, will not replace tau in this reaction, indicating that tau's unique ability to bind to DNA polymerase III holding chipsi in the same complex is essential. All of our findings are consistent with chipsi strengthening DNA polymerase III holoenzyme interactions with the SSB-coated lagging strand at the replication fork, facilitating complex assembly and elongation. 相似文献
24.
1. While the effects of benzodiazepines on human memory have been extensively studied little is known about the effects of these agents on attentional processes. The authors studied the effects of a single dose of triazolam on selective visual-spatial attention using a double blind, placebo controlled design. 2. In each of 2 sessions 12 normal volunteers ingested either 0.25 mg of triazolam or placebo. Attentional performance was evaluated using two versions of the covert orienting paradigm which measured automatic (exogenous) and controlled (endogenous) aspects of attentional orienting, respectively. 3. Triazolam selectively modified performance on automatic orienting to exogenous cues. Specifically, triazolam increased the facilitation of target detection seen at shorter (150 msec) SOA's. This may indicate an increase in facilitation and a reduction in inhibition or a slowing of the time course of the biphasic attentional effect normally resulting from exogenous cuing. 4. These results indicate the importance of using experimental paradigms which effectively dissociate endogenous and exogenous mechanisms of spatial orienting in studies evaluating the effects of pharmacological agents on visual-spatial attention. 相似文献
25.
26.
A microorganism of the genus Pseudomonas has been isolated from the soil by enrichment culture techniques with linalool(I) as the sole source of carbon and energy. The organism is also capable of utilizing limonene, citronellol, and geraniol as substrates but fails to grow on citral, critranellal, and 1,8-cineole. Fermentation of linalool by this bacterium in a mineral salt medium results in the formation of 10-hydroxylinalool(II), oleuropeic acid (IX), 2-vinyl-2-methyl-5-hydroxyisopropyl-tetraphydrofuran)linalool oxide, V), 2-vinyl-2-methyl-tetrahydrofuran-5-one(unsaturated lactone, VI), and few unidentified minor metabolities. Probable pathways for the biodegradation of linalool are presented. 相似文献
27.
Groups of day-old chicks with varying levels of parental antibody were vaccinated against Newcastle disease (B1 strain) with a commercially available device which simultaneously debeaks the chick and emits a fine spray of vaccine into its trachea. Some groups were also vaccinated (B1 or Lasota strain) with a commercially available vaccine sprayer at 9 days, 14 days, or 9 and 25 days of age. Response to vaccine was evaluated once each week during the experimental period of approximately 8 weeks HI titers were determined and 10 chicks were challenged with the Texas GB strain of Newcastle disease virus. In chicks with low to moderate levels of maternal antibody a satisfactory antibody response was attained by vaccination at 1 day of age, and in most cases resistance to challenge was evident by 3 weeks of age. Intratracheal vaccination of chicks with extremely high levels of maternal antibody had a minimal antibody response. All groups of chicks spray vaccinated at 9, 14, or 9 and 25 days of age showed a marked increase in antibody titer regardless of whether they had been vaccinated at 1 day of age. 相似文献
28.
A microorganism capable of degrading DL-mandelic acid was isolated from sewage sediment of enrichment culture and was identified as Pseudomonas convexa. It was found to metabolize mandelic acid by a new pathway involving 4-hydroxymandelic acid, 4-hydroxybenzaldehyde, 4-hydroxybenzoic acid, and 3,4-dihydroxybenzoic acid as aromatic intermediates. All the enzymes of the pathway were demonstrated in cell-free extracts. L-Mandelate-4-hydroxylase, a soluble enzyme, requires tetrahydropteridine, nicotinamide adenine dinucleotide phosphate, reduced form, and Fe2+ for its activity. The next enzyme, L-4-hydroxymandelate oxidase (decarboxylating), a particulate enzyme, requires flavine adenine dinucleotide and Mn2+ for its activity. A nicotinamide adenine dinucleotide-dependent, as well as a nicotinamide adenine dinucleotide phosphate-dependent, benzaldehyde dehydrogenase has been resolved and partially purified. 相似文献
29.
HM Agrama JM Blackwood CS Brown GW Machiedo BF Rush 《Canadian Metallurgical Quarterly》1976,132(3):418-421
Various types of drains were inserted into the peritoneal cavity of twenty-eight dogs. After one to seven days, all drains failed to show the presence of 200 cc of colored fluid injected intraperitoneally. On autopsy, all tubes were surrounded and occluded by omentum. 相似文献
30.
1 Ephedrine plasma levels have been measured in ten asthmatic patients given a singel dose of ephedrine hydrochloride (22 mg) along and in combination with theophylline and a barbiturate. 2 Pharmacokinetic assessment of the data indicated no significant intra-subject changes in kinetic parameters before or after chronic treatment with ephedrine HCl (11 mg three times a day) alone or in combination. 3 Tolerance to these therapeutic doses, if it occurs, is therefore not disposition-related but rather to pharmacodynamic changes. 相似文献