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1.
利用Northernblot方法分析了不同碳源条件下草菇切型纤维素酶基因(eg1)的表达.结果发现,在含有纤维素的液体培养基中生长10d,eg1在草菇菌丝中有高效表达;纤维二糖、α-乳糖、β-乳糖,也能诱导eg1的表达,但和纤维素相比,eg1的表达量相对较低,并且它们的诱导效应在加入这类糖12h后迅速减弱;槐糖和龙胆二糖的诱导作用非常弱.在天然稻草为基质的固体栽培料生长时,草菇eg1的表达和草菇菌丝生长与出菇相对应,在菌丝生长期(d8)可见eg1的表达,d12时菌丝已长满,表达减弱,在出菇及菇体的分化及增大期,eg1的表达量逐渐增强,在成熟期达到最高水平;表明在草菇菇体发育中需要更多碳源及能源的补充,eg1在这方面起着非常重要的作用.图4参14  相似文献   
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Near infrared (NIR) spectroscopy has been found to be one of the most important characterization tools for polymeric materials based on comparatively simple NIR-favorable chemical groups (i.e., C–H, O–H, and N–H). This paper focuses on characterizing degradation of cotton cellulosic fibers in a historical textile—‘Curtain Dress’ in the famous movie Gone With the Wind through NIR spectroscopy, and investigating morphological and molecular changes associated with appearance change such as discolorations in the same cotton textiles. In this study, we did on-site testing on the ‘Curtain Dress’ with the Brimrose Luminar 5030 NIR-analyzer and analyzed the NIR spectroscopy results at eight locations where different degrees of discoloration occurred on the dress. The study identified the wavelength bands according to NIR spectral absorbancies of the typical functional groups in cellulosic fibers such as C–H, C–O and O–H stretches, compared the absorbance intensities at three main wavelengths, and investigated discoloration in different areas via principal component analysis. The combination factor scores of the 1st and 2nd principal components, which accounted for 99.09 % variance of vibrations within various groups in a molecule measured through NIR, reflected effectively morphological changes in the fiber’s molecular structure and degrees of discolorations.  相似文献   
4.
A semi-industrial scale test was conducted to thermally treat mixtures of spent oil and askarels at a concentration of 50,000 ppm and 100,000 ppm of polychlorinated biphenyls (PCBs) under a reductive atmosphere. In average, the dry-basis composition of the synthesis gas (syngas) obtained from the gasification process was: hydrogen 46%, CO 34%, CO2 18%, and CH4 0.8%. PCBs, polychlorinated dibenzo-p-dioxins, and polychlorinated dibenzofurans (PCDDs/PCDFs) in the gas stream were analyzed by high-resolution gas chromatography (GC)-mass spectrometry. The coplanar PCBs congeners 77, 105, 118, 156/ 157, and 167 were detected in the syngas at concentrations < 2 x 10(-7) mg/m3 (at 298 K, 1 atm, dry basis, 7% O2). The chlorine released in the destruction of the PCBs was transformed to hydrogen chloride and separated from the gas by an alkaline wet scrubber. The concentration of PCBs in the water leaving the scrubber was below the detection limit of 0.002 mg/L, whereas the destruction and removal efficiency was > 99.9999% for both tests conducted. The concentration of PCDDs/PCDFs in the syngas were 8.1 x 10(-6) ng-toxic equivalent (TEQ)/m3 and 7.1 x 10(-6) ng-TEQ/m3 (at 298 K, 1 atm, dry basis, 7% O2) for the tests at 50,000 ppm and 100,000 ppm PCBs, respectively. The only PCDD/F congener detected in the gas was the octachloro-dibenzo-p-dioxin, which has a toxic equivalent factor of 0.001. The results obtained for other pollutants (e.g., metals and particulate matter) meet the maximum allowed emission limits according to Mexican, U.S., and European regulations for the thermal treatment of hazardous waste (excluding CO, which is a major component of the syngas, and total hydrocarbons, which mainly represent the presence of CH4).  相似文献   
5.
Acoustic duets—in which the female reveals herself to the advertising male—are a common means of establishing a temporary, pre-mating pair bond within Phaneropterinae katydids. Such duets, however, are especially susceptible to eavesdropping males that orient to signaling females and interrupt the established duet. It would therefore be advantageous for an advertising male to protect his investment in a duet from eavesdroppers. Male Scudderia pistillata katydids produce acoustic advertisement calls after which a conspecific female enters the duet by responding during a specific time-window with her own call, one or more acoustic ticks. We demonstrate here that when a duet is occurring in the presence of other calling males, the focal male produces a single acoustic tick that has a spectrum similar to that of the female’s tick and occurs during the time-window in which the female would respond to his advertisement call within the duet. The male acoustic tick may confound eavesdropping males if they have difficulty performing accurate phonotaxis to a female sound source when sounds arrive from two locations. We tested this hypothesis in laboratory arenas and determined that silent males eavesdrop on advertising male’s duets and accurately locate his female. Moreover, we found that the added acoustic tick produced by advertising males serves to mimic the female response and reduces the accuracy of eavesdropping males to localize the female. Therefore, male ticks appear to act as a form of pre-copulatory acoustic mate guarding of the calling male’s temporary pair bond with the female.  相似文献   
6.
Gender, although gaining attention, remains under-researched in disaster risk reduction protocols and response and recovery efforts. This study examines women's experiences of two disasters in small towns in the United States, utilising qualitative interviews with residents of Granbury and West, Texas, during the first year of disaster recovery. Granbury was struck by an EF-4 tornado on 15 May 2013, whereas an explosion occurred at a local fertiliser facility in West on 17 April 2013. The paper explores how women's experiences of inter-gender power dynamics in decision-making, the prioritisation of childcare, and women's participation in the community affect their post-disaster recovery. Previous research highlights different forms of human response and recovery vis-à-vis ‘natural’ and technological disasters, with less attention paid to gender differences. The results point to the persistent, and similar, effect of gender stratification on women's experiences across different types of disasters in the US and the continued importance of gender-sensitive disaster policies and programmes.  相似文献   
7.
Abstract

A semi-industrial scale test was conducted to thermally treat mixtures of spent oil and askarels at a concentration of 50,000 ppm and 100,000 ppm of polychlorinated biphenyls (PCBs) under a reductive atmosphere. In average, the dry-basis composition of the synthesis gas (syngas) obtained from the gasification process was: hydrogen 46%, CO 34%, CO2 18%, and CH4 0.8%. PCBs, polychlorinated dibenzo-p-dioxins, and polychlorinated dibenzofurans (PCDDs/PCDFs) in the gas stream were analyzed by high-resolution gas chromatography (GC)-mass spec-trometry. The coplanar PCBs congeners 77, 105, 118, 156/157, and 167 were detected in the syngas at concentrations <2 ×10?7 mg/m3 (at 298 K, 1 atm, dry basis, 7% O2). The chlorine released in the destruction of the PCBs was transformed to hydrogen chloride and separated from the gas by an alkaline wet scrubber. The concentration of PCBs in the water leaving the scrubber was below the detection limit of 0.002 mg/L, whereas the destruction and removal efficiency was >99.9999% for both tests conducted. The concentration of PCDDs/PCDFs in the syngas were 8.1 ×10?6 ng-toxic equivalent (TEQ)/m3 and 7.1 × 10?6 ng-TEQ/m3 (at 298 K, 1 atm, dry basis, 7% O2) for the tests at 50,000 ppm and 100,000 ppm PCBs, respectively. The only PCDD/F congener detected in the gas was the octachloro-dibenzo-p-dioxin, which has a toxic equivalent factor of 0.001. The results obtained for other pollutants (e.g., metals and particulate matter) meet the maximum allowed emission limits according to Mexican, U.S., and European regulations for the thermal treatment of hazardous waste (excluding CO, which is a major component of the syngas, and total hydrocarbons, which mainly represent the presence of CH4).  相似文献   
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利用Northern blot方法分析了不同碳源条件下草菇內切型纤维素酶基因(eg1)的表达.结果发现,在含有纤维素的液体培养基中生长10 d,eg1在草菇菌丝中有高效表达;纤维二糖、α-乳糖、β-乳糖,也能诱导eg1的表达,但和纤维素相比,eg1的表达量相对较低,并且它们的诱导效应在加入这类糖12 h后迅速减弱;槐糖和龙胆二糖的诱导作用非常弱.在天然稻草为基质的固体栽培料生长时,草菇eg1的表达和草菇菌丝生长与出菇相对应,在菌丝生长期(d 8)可见eg1的表达,d 12时菌丝已长满,表达减弱,在出菇及菇体的分化及增大期,eg1的表达量逐渐增强,在成熟期达到最高水平;表明在草菇菇体发育中需要更多碳源及能源的补充,eg1在这方面起着非常重要的作用. 图4 参14  相似文献   
10.
Seagrass communities dominate the Laguna Madre, which accounts for 25% of the coastal region of Texas. Seagrasses are essential to the health of the Laguna Madre (LM) and have experienced an overall decline in coverage in the Lower Laguna Madre (LLM) since 1967. Little is known on the existing environmental status of the LLM. This study focuses on the trace metal chemistry of four micronutrient metals, Fe, Mn, Cu, and Zn, and two non-essential metals, Pb and As, in the globally important seagrass Thalassia testudinum. Seasonal trends show that concentrations of most essential trace metals increase in the tissue during the summer months. With the exception of (1) Cu in the vertical shoot and root, and (2) Mn in the roots, no significant positive correlation exists between the rhizosphere sediment and T. testudinum tissue. Iron indicates a negative correlation between the morphological units and the rhizosphere sediments. No other significant relationship was found between the sediments and the T. testudinum tissue. Mn was enriched up to 10-fold in the leaf tissue relative to the other morphological units and also enriched relative to the rhizosphere sediments. Both Cu and Mn appear to be enriched in leaf tissue compared to other morphological units and also enriched relative to the Cu and Mn in the rhizoshpere sediments. Sediments cores taken in barren areas were slightly elevated in Zn relative to the rhizosphere sediments, whereas no other metals showed statistical differences between barren sediment cores and rhizosphere sediments. However, no correlation was measured in T. testudinum tissue and Zn in rhizosphere sediments. Previous studies suggested that Fe/Mn ratios could indicate differences between seagrass environments. Our results indicate that there is an influence from the Rio Grande in the Fe/Mn signature in sediments, and that ratio is not reflected in the T. testudinum tissue. The results from this study show that the LLM contains trace metal concentrations less than or equal to values for uncontaminated locations worldwide. In addition, there appears to be a complex partitioning in the trace metals in the morphological units of T. testudinum tissue and that analysis only of the leaf may not be indicative of the trace metal levels in this important seagrass species.  相似文献   
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