Preferencje help
Widoczny [Schowaj] Abstrakt
Liczba wyników

Znaleziono wyników: 7

Liczba wyników na stronie
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 1 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników

Wyniki wyszukiwania

help Sortuj według:

help Ogranicz wyniki do:
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 1 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników
The environmental challenge of crude oil-contaminated soil is difficult to address due to its complicated components and the mechanism of material transformation. In order to study the bioremediation of soil contaminated by crude oil, we designed five simulation test systems: a sterilization system, an oxygenated and water-controlled system, a nitrogen (N)/phosphorus (P) adjusted system, a broth-added system, and a double-broth-added system. The results show that the highest removal of crude oil from soil was increased to 34.23% by regulating the micro-ecological environment after 91 days in a simulation system. Regulating N and P can effectively strengthen the mineralization action of microorganisms on crude oil. Biodegradation had the most effect on the removal of oil, accounting for more than 58% of the total removal. Moreover, mineralization was dominant in biodegradation. Degradation of crude oil components was alkanes-based, accounting for 50 to 80% of total oil removal. By regulating moisture, temperature, oxygen content, N/P levels, and enrichment broth, the half-life of crude oil in a simulation system can be shortened to 182 days.
The system of dynamic leaching was designed for samples of a coal gasification residual from a coalto-methanol plant in northwestern China in order to investigate the leaching behavior of four potentially hazardous elements – Hg, Cr, As, and Pb – in the coal gasification residual and investigate the impacts of the leaching time, size of the samples, and pH of the leaching solution on the leaching behavior of elements. The concentrations of elements in the leachate samples were all determined by inductively coupled plasma-mass atomic spectrometry (ICP-MS). The results showed that the leaching time, size of the samples, and pH of the leaching solution played an important role in affecting the leaching behavior of the selected elements from the coal residual samples. All trends were in decreasing order of significance as the leaching time went on and most leached concentrations reached the maximum at the initial stage of leaching experiments (from hours 0 to 4) accounting for 94.44%. The 80-mesh sample had the different leaching curve from the 10-mesh and 40-mesh samples for the same element because different forms of the heavy metals existed on the different-size samples.
Sera from 534 pet dogs and 335 pet cats from Beijing (China) were tested for anti-Toxoplasma gondii antibodies using an enzyme-linked immunosorbent assay or the latex agglutination test. The seropositivity by year, season, sex and age was analysed. Overall, 128 dogs (24.0%) and 50 cats (14.9%) had antibodies to T. gondii. When analysed by season, the highest seroprevalence was found in spring for dogs (31.3%) and cats (25.1%), and the differences in seroprevalence by season was statistically significant in cats (P<0.01) but not in dogs. The seroprevalence in male dogs (23.7%) and cats (15.1%) were slightly higher than their female counterparts (18.0% in dogs and 12.3% in cats). There was no obvious pattern of seropositivity or significant difference in different age groups in dogs or cats; nonetheless, a high proportion of dogs at 4 years of age were positive to T. gondii (31.8%) while cats with relatively high seropositivity rates were at 1 or 3.4 years of age (13.14%).
Coal gasification coarse cinder (CGCC) is the main waste in the coal gasification industry, containing low calorific value but high heavy metal residuals. To achieve environmental toxicity stabilization and waste recycling, we developed a manufacturing method of multiple-functional ceramsite from CGCC by pelletizing and sintering. By altering key parameters during the manufacturing process (including CGCC content, sintering temperature, and time), the physical properties and leaching toxicity of ceramsite were evaluated. Sintering temperature was identified with a significantly positive relationship with ceramsite’s compressive strength, whereas CGCC content was negatively correlated with water adsorption. The highest compressive strength (24.00 MPa) and relatively lower water absorption (21.36%) was achieved at 50% CGCC content and 1,150ºC sintering for 30 min. The toxicity tests showed acceptable leaching heavy metals with minimal environmental impact. Considering the energy conservation and the maximal recycling of CGCC, optimal ceramsite manufacturing is suggested as 50% CGCC content and 1,150ºC/10 min sintering temperature/time. Our results indicated that multiple-functional ceramsite manufacturing is a low-cost and environmentally friendly approach for CGCC recycling.
A repetitive sequence of 411 bp, named pSaO5₄₁₁, was identified in the Secale africanum genome (Rᵃ) by random amplified polymorphic DNA (RAPD) analysis of wheat and wheat-S. africanum amphiploids. GenBank BLAST search revealed that the sequence of pSaO5₄₁₁ was highly homologous to a part of a Ty1 -copia retrotransposon. Fluorescence in situ hybridization (FISH) analyses indicated that pSaO5₄₁₁ was significantly hybridized to S. africanum chromosomes of a wheat-S. africanum amphiploid, and it was dispersed along the Secale chromosome arms except the terminal regions. Basing on the sequence of pSaO5₄₁₁, a pair of sequence-characterized amplified region (SCAR) primers were designed, and the resultant SCAR marker was able to target both cultivated rye and the wild Secale species, which also enabled to identify effectively the S. africanum chromatin introduced into the wheat genome.
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 1 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.