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101.
The results of experimental investigation of pyrolysis, ignition, and combustion of biofuels (wood chips, date stones) and their processing products (charcoal, pellets) at temperatures of 250–1200°C are presented. The influence of the yield of volatiles on the ignition and the mode of combustion of a particle has been considered. The results are compared with published data on the combustion of pellets and brown coals and with the data calculated according to the classical diffusion-kinetic model.  相似文献   
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The present study demonstrates a modified in situ emulsion polymerization (EP) approach convenient for the formation of polypyrrole/graphene (PPy/GN) nanocomposites with harnessed conductivities. A series of PPy/GN nanocomposites were prepared by loading different weight percent (wt %) of GN during in situ EP of pyrrole monomer. The polymerization was carried out in the presence of dodecyl benzene sulfonic acid, which acts as an emulsifier and protonating agent. The microstructures of the nanocomposites were studied by scanning electron microscopy, transmission electron microscopy, X‐ray diffraction, Fourier transform infrared, X‐ray photoelectron spectroscopy, UV–vis spectroscopy, Raman spectroscopy, photoluminescence spectroscopy and thermogravimetric analyses. The electrical conductivities of the nanocomposite pellets pressed at different applied pressures were determined using four probe analyzer. The electrical conductivities of the nanocomposites were considerably enhanced as compared to those of the individual PPy samples pressed at the same pressures. An enhanced conductivity of 717.06 S m?1 was observed in the sample with 5 wt % GN loading and applied pressure of 8 tons. The results of the present study signify that the addition of GN in the PPy polymer harnesses both electrical and thermal properties of the polymer. Thus, PPy/GN nanocomposites with superior properties for various semiconductor applications can be obtained through direct loading of GN during the polymerization process. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41800.  相似文献   
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BACKGROUND: The authors report observed 10-year brachytherapy results in the treatment of 152 consecutive patients with clinically organ-confined prostate carcinoma. METHODS: One hundred and fifty-two consecutive patients with T1-T3, low to high Gleason grade, prostate carcinoma were treated between January 1987 and June 1988 at Northwest Hospital in Seattle, Washington. Their median age was 70 years (range, 53-92 years). Of these 152 patients, 98 (64%) received an iodine-125 implant alone (Group 1), and the remaining 54 patients (36%), who were judged to have a higher risk of extraprostatic extension, also were treated with 45 gray (Gy) of external beam irradiation to the pelvis (Group 2). No patient underwent lymph node sampling, and none received androgen ablation therapy. Multivariate regression and the Mann-Whitney rank sum test were used for statistical analysis. Preoperative patient data with associated success or failure outcomes at 10 years after treatment were used for training and validating a back-propagation neural network prediction program. RESULTS: The average preoperative prostate specific antigen (PSA) value, clinical stage, and Gleason grade were 11.0 ng/mL, T2, and 5, respectively. The median posttreatment follow-up was 119 months (range, 3-134 months). Overall survival 10 years after treatment was 65%. At last follow-up only 3 of the 152 patients (2%) had died of prostate carcinoma. Ninety-seven patients (64%) remained clinically and biochemically free of disease at 10 years of follow-up and had an average PSA value of 0.18 ng/mL (range, 0.01-0.5 ng/mL). In these patients a period of 42 months was required to reach the average PSA (0.5 ng/mL). The median to last PSA follow-up was 95 months (range, 3-134 months). Postoperative needle biopsies were negative in 56% of patients, positive in 15% of patients, and not available in 29% of patients. Only 6% of patients developed bone metastasis. At 10 years there was no statistically significant difference in treatment outcome between patients who received iodine-125 alone, and those who received iodine-125 with 45-Gy external beam irradiation (P = 0.08). Nevertheless, in these two groups preoperative PSA, stage, and Gleason grade were significantly different (P < 0.01). In the artificial neural network analysis, pretreatment serum PSA was the most accurate predictor of disease-free survival. CONCLUSIONS: Percutaneous prostate brachytherapy is a valid and efficient option for treating patients with clinically organ-confined, low to high Gleason grade, prostate carcinoma. Observed 10-year follow-up documents serum PSA levels superior to those reported in several published external beam irradiation series, and comparable to those published in a number of published radical prostatectomy series.  相似文献   
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Russian urban planning and government are undergoing a metropolitan turn. The Russian central government is seeking to spatially rebalance the Russian economy by creating new economic centres and introducing metropolitan-level urban planning and government for selected core cities and adjacent municipalities. From the urban planning perspective, metropolisation aims to promote better coordination within functional urban areas. Using the current debates in urban planning and economic geography, this paper examines the origins, content, and economic implications of this state-led metropolisation. It concludes that although some material conditions for metropolisation are present, cities may not be able to fulfil the vision of new ‘economic engines’ because of deeply embedded structural problems in the Russian economy and the current weakness of metropolitan governments.  相似文献   
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The present study was carried out to 1) evaluate the viability of in vitro fertilized zygotes after microinjection of DNA, 2) assess the influence of oocyte quality upon the development rate of embryos when injected with DNA, and 3) determine the integration frequency of green fluorescent protein DNA into microinjected embryos. Oocytes were aspirated from ovaries of nine nonlactating Holsteins and were categorized into grades A, B, C, and D. At 16 h after in vitro fertilization, approximately half of the pronuclear stage presumptive zygotes were classified as having 1 pronucleus or 2 pronuclei, and they were microinjected with DNA constructs. A potential predictor of DNA integration frequency at d 10 was assessment of the incidence of green fluorescing embryos. The proportion of cleaved embryos that developed to morulae or blastocysts was not different between groups with 1 pronucleus injected (45%), 1 pronucleus uninjected (64%), or 2 pronuclei injected (49%). However, the development of morulae or blastocysts was higher in the group with 2 pronuclei uninjected (69%). The overall developmental score of green fluorescent protein-positive embryos was higher for grade A oocytes (1.3 +/- 0.1) than for grade B (0.8 +/- 0.1), C (0.6 +/- 0.1), or D (0.3 +/- 0.1) oocytes. The results show that production of transgenic bovine blastocysts can occur from the microinjection of a presumptive zygote having only one visible pronucleus. Initial oocyte quality is an important factor in selection of oocytes suitable for microinjection of DNA and for preimplantation development to produce bovine transgenic embryos.  相似文献   
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