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81.
The C and N mineralization characteristics of two organic N fertilizers were determined in a soil-less incubation system at three temperature regimes. Protox (derived from activated sewage sludge) initially degraded more rapidly by microbial action compared with dried blood. However, dried blood released more CO2-C and inorganic N towards the end of the incubation periods. The rate of microbial degradation increased with temperature. Mineralization characteristics of protein-based N sources are discussed in relation to organic N nutrition of vegetable crops. 相似文献
82.
The effect of the shape and size of the components on the stability of mixtures was evaluated in binary mixtures of drug and carrier. Aspirin was used as model drug; spray-dried lactose and microcrystalline cellulose were used as carriers. The coefficient of variation (CV) of the drug in the mixture at various time intervals during mixing was used as a measure of homogeneity. The stability of mixtures was assessed under conditions that were conducive to segregation—in this case, prolonged mixing. The pattern of change in CV with time was analyzed in terms of convective, shear, and diffusive mixing stages. The variation resulting from a change in the shape of the carriers was smaller than that resulting from size differences. The segregation rate constant, calculated on the assumption of a first-order mixing process, was found to be larger in mixtures having components of different shape than in mixtures having components of similar shape. In mixtures of micronized drug and carrier, the pattern of change in the CV of drug with mixing time was attributed to the distribution of agglomerates of micronized drug during convective mixing, followed by shearing of agglomerates and, finally, the distribution of the primary particles during diffusive mixing. Mixtures of non-cohesive powders of similar size and shape behaved like random mixtures of non-interacting components. 相似文献
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1.简介
MIPS科技的MIPS32 74KTM内核系列采用全新的超标量、无序流水线架构,可通过可合成的方法实现优化的性能.
…… 相似文献
86.
Biodegradation of phenol was carried out using Nocardia hydrocarbonoxydans immobilised on glass beads, in a pulsed plate bioreactor. The effect of operating parameters like frequency of pulsation and amplitude of pulsation on the performance of pulsed plate bioreactor for biodegradation of phenol in a synthetic wastewater containing 500ppm phenol was studied. Axial concentration profile measurements revealed that the pulsed plate bioreactor shows continuous stirred tank behaviour. As the amplitude was increased, percentage degradation increased, reaching 100% at amplitude of 4.7cm and higher. Introduction of pulsation is found to increase the percentage degradation. Percentage degradation has increased with increase in frequency and 100% degradation was achieved at 0.5s(-1) and above. Biofilms developed in a non-pulsed bioreactor were thicker than those in the pulsed plate bioreactor. But biofilm thickness remained almost constant with increasing frequency. Biofilm density was found to be influenced by pulsation. The time required to reach steady state was more for pulsed reactor than the non-pulsed reactor and this start-up time had increased with increase in frequency of pulsation. The performance studies reveal that the pulsed plate bioreactor with immobilized cells has the potential to be an efficient bioreactor for wastewater treatment. 相似文献
87.
Bagasse is one of the important biomass sources, which is used as a fuel in the sugar industry in India. As a result, large quantities of fly ash are generated and create a serious disposal problem. This is further aggravated by the presence of unburned bagasse mainly as carbonised fibre. In this study, the unburned carbon in bagasse fly ash is characterized by thermal analysis, electron microscopy and adsorption. The carbon particles can be separated from oxide fraction of fly ash by floating it in water. This process increases the loss on ignition from 20–30% to 80%. N2 adsorption measurements give BET surface areas of ~200 m2/g for the separated carbons. Analysis of the isotherms indicates a large fraction of pores in the size range of 10–12 Å. Scanning and transmission electron microscopy studies show that the unburned carbon is amorphous and the morphology retains the cellular characteristics of the parent bagasse fibres. 相似文献
88.
Vidya Sagar Thalapala Preeth Raguraman Koppala Guravaiah 《International Journal of Communication Systems》2024,37(8):e5739
Currently, networking technologies are pivoting towards software-defined networking (SDN) due to its easy management and centralized control system. The SDN network metrics, such as latency, scalability, robustness, and reliability largely depends on controller placement in the network domain. In view of betterment and best progression of network quality, the above mentioned network metrics need to be laid more emphases by considering controller placement. To achieve better network quality, an HR-DO (high reliable–delay optimized controller placement) is proposed. Fuzzy C-means, a meta-heuristic optimization algorithm, is used to optimize the number of controllers required in the network due to its effectiveness in cluster selection. It also eases the network latency. In addition, a minimal cut set-based Boolean logic approach and natural connectivity metric are used to improve the reliability and robustness of SDN with minimum worst-case latency. To check the performance, the proposed HR-DO is implemented on a topology-zoo network data set (OS3E and Chinanet). For comparison purposes, OCPA and K-means algorithms are taken into the account of latency, reliability, and robustness as parameters. The performance of the HR-DO approach outperforms over K-means and OCPA with respect to latency, reliability, and robustness. 相似文献
89.
Vidya Tikoo Alan H. Scragg Stuart W. Shales 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》1997,68(4):425-431
A microalga (VT-1) was isolated from pentachlorophenol (PCP) treated water. Its growth and PCP tolerance was compared with two known strains of Chlorella and it was found to be more tolerant with an IC50 (24–25 mg dm−3) value twice that of C. vulgaris. The ability of VT-1 to degrade PCP was tested using uniformly labelled PCP, and 14CO2 was released, indicating mineralisation. 14CO2 was not released in the presence of the other microalgae and only occurred in the light. Release was also stimulated by the presence of glucose in the light. © 1997 SCI. 相似文献
90.
Vidya Rajagopalan Vanessa Schmithorst Alexander El-Ali William Reynolds Vincent Lee Julia Wallace Jacqueline Weinberg Jennifer Johnson Jodie Votava-Smith Jennifer Adibi Ashok Panigrahy 《International journal of molecular sciences》2022,23(23)
The relationship between maternal risk factors (MRFs) (particularly pre-gravid obesity, diabetes, and hypertension) and congenital heart disease (CHD) to placental and fetal brain outcomes is poorly understood. Here, we tested the hypothesis that MRF and CHD would be associated with reduced intrinsic placental and fetal brain function using a novel non-invasive technique. Pregnant participants with and without MRF and fetal CHD were prospectively recruited and underwent feto-placental MRI. Using intrinsic properties of blood oxygen level dependent imaging (BOLD) we quantified spatiotemporal variance of placenta and fetal brain. MRFs and CHD were correlated with functional characteristics of the placenta and fetal brain. Co-morbid MRF (hypertension, diabetes, and obesity) reduced spatiotemporal functional variance of placenta and fetal brain (p < 0.05). CHD predicted reduced fetal brain temporal variance compared to non-CHD (p < 0.05). The presence of both MRF and CHD was associated with reduced intrinsic pBOLD temporal variance (p = 0.047). There were no significant interactions of MRFs and CHD status on either temporal or spatial variance of intrinsic brain BOLD. MRF and CHD reduced functional characteristic of placenta and brain in fetuses. MRF modification and management during pregnancy may have the potential to not only provide additional risk stratification but may also improve neurodevelopmental outcomes. 相似文献