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61.
62.
L.S. Panchakarla Author VitaeAuthor Vitae C.N.R. Rao Author Vitae 《Inorganica chimica acta》2010,363(15):4163-4174
Multi-walled, single-walled and double-walled carbon nanotubes as well as graphene can be doped with boron and nitrogen. B2H6 has been generally used as the boron source while NH3 or pyridine is employed as the nitrogen source. Doping carbon nanotubes and graphene with boron and nitrogen brings about significant changes in the electronic structure and properties. Such doping not only results in desirable properties but also allows manipulation of properties for specific purposes. Doping with boron- and nitrogen-causes marked changes in the Raman spectra of the carbon nanostructures. In this article, we present the synthesis, characterization and properties of boron- and nitrogen-doped carbon nanotubes and graphene. 相似文献
63.
There was little release of extractable SO4-S during four weeks from CS2 applied by injecting into two S-deficient soils. In this incubation experiment, the rate of CS2 was 30 μg S g−, placement was injection at 9 cm depth, soil temperature was 20°C, and soil moisture tension was 33 kPa. The yield of barley
forage after seven weeks in the greenhouse showed only small increases from 10 or 30 μg S g−1 of CS2 as compared to Na2SO4, on the two soils.
While CS2 supplied little plant available S in the short term, it was an effective inhibitor of nitrification. In the laboratory, or
in the field, the injection of CS2 (with N fertilizers) at a point 9 cm into the soils either stopped or reduced nitrification. In one laboratory experiment,
35 μg of CS2 g−1 of soil with urea reduced nitrification for at least four weeks; and in another experiment 20 μg of CS2 g−1 of soil with aqua NH3 nearly or completely inhibited nitrification at 20 days. In two field experiments, 3 and 12 μg of CS2 g−1 of soil (or 6 and 24 kg ha−1) with aqua NH3 inhibited nitrification from October to the subsequent May. In addition, CS2 reduced the amount of ammonium produced from the soil N, both in these two field experiments and in the laboratory experiments.
That is to say, CS2 injected at a point, inhibited both nitrification and ammonification.
In other field experiments, CS2 at a rate of 10 kg ha−1 was injected in bands 9 cm deep with urea in October, and by May there was still reduced nitrification. Less than half of
the fall-applied urea alone was recovered as mineral N, but with the application of CS2 the recovery was increased to three-quarters.
The yield and N uptake of barley grain was increased where fall-applied banded urea or aqua NH3 received banded CS2, (NH4)2CS3, or K2CS3. The average increase in yield from fall-applied fertilizer, from inhibitor with fall-applied fertilizer, and from spring-applied
fertilizer was 800, 1370, and 1900 kg ha−1, respectively. In the same order, the apparent % recovery of fertilizer N in grain was 24, 42, and 60. 相似文献
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Drosophila suzukii is an invasive pest causing severe damages to a large panel of cultivated crops.To facili tate its biocontrol with stratcgies such as sterile or incompatible insect techniques,D.suzukid must be mass-produced and then stored and transported under low temperature.Prolonged cold exposure induces chill injuries that can be mitigated if the cold period is interrupted with short warming intervals,referred to as fluctuating thermal regimes(FTR).In this study,we tested how to optimally use FTR to extend the shelf life of D.suzukii under cold storage.Several FTR parameters were asessed:temperature(15,20,25℃),duration(0.5,1,2,3 h),and frequency(every 12,24,36,48 h)of warming intervals,in two wild-type lines and in two developmental stages(pupac and adults).Generally,FTR improved cold storage tolerance with respect to constant low temperatures(CLT).Cold mortality was lower when recovery temperature was 20℃ or higher,when duration was 2 h per day or longer,and when warming interruptions occurred frequently(every 12 or 24 h).Applying an optimized FTR protocol to adults greatly reduced cold mortality over long-term storage(up to 130 d).Consequences of FTR on fitness-related traits were also investigated.For adults,poststorage survival was unaffected by FTR,as was the case for female fecundity and male mating capacity.On the other hand,when cold storage occurred at pupal stage,postorage survival and male mating capacity were altered under CLT,but not under FTR.After storage of pupae,female fecundity was lower under FTR compared to CLT,suggesting an energy trade-off between repair of chill damages and C22 production.This study provides detailed information on the application and optimization of an FTR-based protocol for cold storage of D.suzuki that could be useful for the biocontrol of this pest. 相似文献
68.
Solana Abraham Gisela Castillo Viviana Díaz Guido VanNieuwenhove Gabriela Murúa Juan Rull 《Insect Science》2020,27(3):545-557
Seminal gifts range from important material donations to items that provide little direct benefit to females. Promiscuous, female silk corn flies Euxesta eluta expel and consume male ejaculates immediately after mating. The evolution and function of this peculiar behavior are currently unknown. We performed a series of experiments aimed to: determine if females under different dietary regimes derive nutrients or water for survival and/or reproduction from ejaculate consumption, if males suffer a fitness cost from supplying females with ejaculates, and if females prefer to mate and/or are more likely to store sperm from well fed than nutritionally stressed presumably inferior males. Experiments revealed that protein deprived E. eluta females derive nutrients for ovarian development through consumption of ejaculates of protein fed males. No seminal products affecting survival appear to be transferred in the consumed ejaculate. However, ovarian development, in contrast to testes growth, occurs in detriment of longevity. Females preferred to mate with protein fed males, yet sperm retention in spermathecae was extremely rare after a single mating. This finding suggests that females could be exerting post copulatory control. A key question that remained to be addressed for the understanding of this puzzling and promiscuous mating system is what ecological factors or male traits drive females to retain sperm from one or several males in order to achieve and/or maximize fertilization potential. 相似文献
69.
Ainara Pealver‐Cruz Elisa Garzo Ins Prieto‐Ruiz Miguel Díaz‐Carro Ana Winters Arnzazu Moreno Alberto Fereres 《Insect Science》2020,27(3):558-570
The continuous rise of CO2 concentrations in the atmosphere is reducing plant nutritional quality for herbivores and indirectly affects their performance. The whitefly (Bemisia tabaci, Gennadius) is a major worldwide pest of agricultural crops causing significant yield losses. This study investigated the plant‐mediated indirect effects of elevated CO2 on the feeding behavior and life history of B. tabaci Mediterranean species. Eggplants were grown under elevated and ambient CO2 concentrations for 3 weeks after which plants were either used to monitor the feeding behavior of whiteflies using the Electrical Penetration Graph technique or to examine fecundity and fertility of whiteflies. Plant leaf carbon, nitrogen, phenols and protein contents were also analyzed for each treatment. Bemisia tabaci feeding on plants exposed to elevated CO2 showed a longer phloem ingestion and greater fertility compared to those exposed to ambient CO2 suggesting that B. tabaci is capable of compensating for the plant nutritional deficit. Additionally, this study looked at the transmission of the virus Tomato yellow leaf curl virus (Begomovirus) by B. tabaci exposing source and receptor tomato plants to ambient or elevated CO2 levels before or after virus transmission tests. Results indicate that B. tabaci transmitted the virus at the same rate independent of the CO2 levels and plant treatment. Therefore, we conclude that B. tabaci Mediterranean species prevails over the difficulties that changes in CO2 concentrations may cause and it is predicted that under future climate change conditions, B. tabaci would continue to be considered a serious threat for agriculture worldwide. 相似文献
70.
Structural equation modelling reveals plant-community drivers of carbon storage in boreal forest ecosystems 总被引:1,自引:0,他引:1
Boreal forest ecosystems are important drivers of the global carbon (C) cycle by acting as both sinks and sources of atmospheric CO2. While several factors have been proposed as determining the ability of boreal forest to function as C sinks, little is known about their relative importance. In this study, we applied structural equation modelling to a previously published dataset involving 30 boreal-forested islands that vary greatly in their historic fire regime, in order to explore the simultaneous influence of several factors believed to be important in influencing above-ground, below-ground and total ecosystem C accumulation. We found that wildfire was a major driver of ecosystem C sequestration, and exerted direct effects on below-ground C storage (presumably through humus combustion) and indirect effects on both above-ground and below-ground C storage through altering plant-community composition. By contrast, plant diversity influenced only below-ground C storage (and even then only weakly), while net primary productivity and decomposition had no detectable effect. Our results suggest that while boreal forests have great potential for storing significant amounts of C, traits of dominant plant species that promote below-ground C accumulation and the absence of wildfire are the most important drivers of C sequestration in these ecosystems. 相似文献