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21.
A. L. Lapidus M. Ya. Shpirt Yu. A. Malinovskaya E. M. Movsumzade D. S. Khudyakov 《Solid Fuel Chemistry》2017,51(6):349-354
Information on the chemical nature and structure of the organic matter of oil shale from different deposits, the composition and distribution of mineral impurities in the volume of oil shale, and the elemental composition of the organic matter is considered in this article. It was found that the composition and properties of oil shale from different deposits are essentially different, and significant differences can also be observed within the limits of a deposit. Oil shale from some deposits contain trace impurity elements such as uranium, molybdenum, vanadium, and rhenium. In a number of cases, the concentrations of such impurities are increased, and their extraction can be of industrial interest. 相似文献
22.
Fluorescent Probe DCVJ Shows High Sensitivity for Characterization of Amyloid β-Peptide Early in the Lag Phase
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Dr. Sureshbabu Nagarajan Prof. Lisa J. Lapidus 《Chembiochem : a European journal of chemical biology》2017,18(22):2205-2211
The aggregation of intrinsically disordered and misfolded proteins in the form of oligomers and fibrils plays a crucial role in a number of neurological and neurodegenerative diseases. Currently, most probes and biophysical techniques that detect and characterize fibrils at high resolution fail to show sensitivity and binding for oligomers. Here, we show that 9-(dicyano-vinyl)julolidine (DCVJ), a class of molecular rotor, binds amyloid beta (Aβ) early aggregates, and we report the kinetics as well as packing of the oligomer formation. The binding of DCVJ to Aβ40 increased its emission intensity with time at 510 nm and produced a second excimer peak at 575 nm. However, DCVJ did not bind to the prefibrillar aggregates of Aβ42, which indicated that the oligomers formed by Aβ40 and Aβ42 were not the same. The F4C F19W mutant of Aβ40, which did not form fibrils, also bound DCVJ, but the emission spectral profile varied from that of the wild-type (WT). Atomic force microscopy images of WT Aβ40, the F4C F19W mutant, and Aβ42 oligomers displayed differences in size and shape, confirming the difference in their DCVJ spectra. The effect of epigallocatechin-3-gallate (EGCG) on the reduction of Aβ42 fibrils was also observed with finer detail than with other techniques. The results of this study show that DCVJ detects early aggregates and provides valuable information regarding the oligomer kinetics, packing, and mechanism of formation. 相似文献
23.
Highly effective cobalt-cement catalysts for the synthesis of aliphatic hydrocarbons from CO and H2, which are formed upon the thermolysis or gasification of oil shale or coals, are considered. The formation of the catalysts
was studied. 相似文献
24.
V. Lapidus 《Building Research & Information》2013,41(1)
Improved design of sleeve anchoring locks could produce considerable saving in the cost of reinforced concrete and raise the level of mechanisation in preparing and prestressing the reinforcement. A method devised at the Technion, Israel, where the author was a Senior Research Fellow at the Faculty of Civil Engineering, offers several economies in labour and materials usage. 相似文献
25.
A. L. Lapidus A. Yu. Krylova Ya. V. Mikhailova L. V. Sineva A. B. Erofeev 《Solid Fuel Chemistry》2011,45(2):71-80
The effect of the nature of the support of a Co catalyst on the synthesis of hydrocarbons from CO, H2, and C2H4 was studied in this work. It was found that the introduction of ethylene into synthesis gas resulted in an increase in the
yield of liquid hydrocarbons. In this case, the conversion of C2H4 was complete and the degree of its involvement into the synthesis of C5+ hydrocarbons depended on the concentration of this component in the starting mixture and the nature of the support. Specific
features of the adsorption of CO and C2H4 on the used Co catalysts were determined using a temperature-programmed desorption method. 相似文献
26.
李科锋 《建设机械技术与管理》2006,19(8):42-44
第八届国际公路水运交通技术与设备展览会(CHINA TRANSPO 2006)将于2006年9月26-29日在北京全国农业展览馆举行。截至目前.参展企业已近300家,包括徐工、柳工、三一重工、中联重科、西筑等筑路机械厂家.中海油、壳牌等道路材料生产企业.中国重型汽车集团、宇通客车、厦门金龙等商用车辆制造企业,尤其引人注目的是,本届展会有十余家省市交通厅局单位设台参展,这是历年来同类展会中不多见的。据悉,目前预订的展位面积已达38000平方米,一场交通行业的国际展览盛宴正在徐徐拉开帷幕。 相似文献
27.
28.
Microsporidia, as a group, cause a wide range of infections, though two species of microsporidia in particular, Enterocytozoon bieneusi and Encephalitozoon intestinalis, are associated with gastrointestinal disease in humans. To date, the mode of transmission and environmental occurrence of microsporidia have not been elucidated due to lack of sensitive and specific screening methods. The present study was undertaken with recently developed methods to screen several significant water sources. Water concentrates were subjected to community DNA extraction followed by microsporidium-specific PCR amplification, PCR sequencing, and database homology comparison. A total of 14 water concentrates were screened; 7 of these contained human-pathogenic microsporidia. The presence of Encephalitozoon intestinalis was confirmed in tertiary sewage effluent, surface water, and groundwater; the presence of Enterocytozoon bieneusi was confirmed in surface water; and the presence of Vittaforma corneae was confirmed in tertiary effluent. Thus, this study represents the first confirmation, to the species level, of human-pathogenic microsporidia in water, indicating that these human-pathogenic microsporidia may be waterborne pathogens. 相似文献
29.
30.
IL Gerner JC N?rregaard OA Jensen JU Prause 《Canadian Metallurgical Quarterly》1998,160(25):3728-3731
The clinicopathological characteristics of 343 naevi of the conjunctiva were studied. A significant increase in the number of naevi excised per year was observed. This may have been caused by an increased exposure to actinic rays. An approximately even distribution was found between the three main locations: caruncle, limbal area and eye ball. Intrastromal naevi were excised at a higher median age than compound naevi, and the lowest median age at excision was for junction naevi, which is in accordance with the known histopathological nature of naevi. Recurrence occurred in nine patients (2.7%), and one had transformed into a malignant melanoma. Eight of the recurring naevi were located in the limbal area. Eight of the nine patients were women, suggesting hormonal factors as a possible cause. Recommendations for the handling of conjunctival naevi are given, based on the present findings and on previous reports. 相似文献