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排序方式: 共有735条查询结果,搜索用时 15 毫秒
41.
Wastewater treatment sludge as a raw material for the production of Bacillus thuringiensis based biopesticides 总被引:5,自引:0,他引:5
Seven wastewater sludges of different origins and types were used as an alternate culture medium for producing Bacillus thuringiensis variety kurstaki HD-1. The sludge samples were used under three different preparations: without pre-treatment, with acid treatment (hydrolysed sludge) and the supernatant obtained after centrifugation of the hydrolysed sludge. The sludge composition varied widely with origin and the type of sludge. Growth and sporulation were evaluated by the total viable cell count and spore count of the preparations. Growth, sporulation and endotoxin production were affected by the sludge origin. Hydrolysed sludge gave the highest viable cell and spore counts while the liquid phase (supernatant) gave the lowest. Non-hydrolysed primary sludge from Valcartier was unable to sustain bacterial growth because of its low pH. Bioassays were conducted against larvae of spruce budworm to evaluate entomotoxic potential of the preparations obtained. In general, sludge hydrolysis increased the entomotoxicity yields. Similar entomotoxicity was observed in Black Lake secondary sludge (4100 IU/microL) as that obtained in the reference soya medium (3800 IU/microL). The use of the sludge supernatant (liquid phase) was not recommended due to the low entomotoxic potential obtained. 相似文献
42.
Parallel architectures involve communication with the aim of fast receiving of complete information at each node. Several architectures have been proposed to overcome the problem of high communicational and computational time complexity for transferring and receiving information. To reduce the complexity of such communication, we have implemented Linear Network Coding (LNC) in the parallel environment. For verification of our approach, we have considered some parallel architecture for implementing network coding approach and examined our results on these networks in a generic environment. We have formulated a standard approach for parallel networks, showing that by applying this approach effect of faulty nodes, information size and communication complexity exponentially decreases with code length. 相似文献
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45.
Indranil Saha Lokesh Kumar Sambasivan Subhas Kumar Ghosh Ranjeet Kumar Patro 《Wireless Networks》2010,16(6):1511-1524
In wireless multi-hop and ad-hoc networks, minimizing power consumption and at the same time maintaining desired properties
of the network topology is of prime importance. In this work, we present a distributed algorithm for assigning minimum possible
power to all the nodes in a static wireless network such that the resultant network topology is k-connected. In this algorithm, a node collects the location and maximum power information from all nodes in its vicinity,
and then adjusts the power of these nodes in such a way that it can reach all of them through k optimal vertex-disjoint paths. The algorithm ensures k-connectivity in the final topology provided the topology induced when all nodes transmit with their maximum power is k-connected. We extend our topology control algorithm from static networks to networks having mobile nodes. We present proof
of correctness for our algorithm for both static and mobile scenarios, and through extensive simulation we present its behavior. 相似文献
46.
B. M. Krishna Usha N. Murthy B. Manoj Kumar K. S. Lokesh 《Journal of Applied Electrochemistry》2010,40(3):663-673
Electrochemical (EC) oxidation of distillery wastewater with low (BOD5/COD) ratio was investigated using aluminum plates as electrodes. The effects of operating parameters such as pH, electrolysis
duration, and current density on COD removal were studied. At a current density of 0.03 A cm−2 and at pH 3, the COD removal was found to be 72.3%. The BOD5/COD ratio increased from 0.15 to 0.68 for an optimum of 120-min electrolysis duration indicating improvement of biodegradability
of wastewater. The maximum anodic efficiency observed was 21.58 kg COD h−1 A−1 m−2, and the minimum energy consumption observed was 0.084 kWh kg−1 COD. The kinetic study results revealed that reaction rate (k) decreased from 0.011 to 0.0063 min−1 with increase in pH from 3 to 9 while the k value increased from 0.0035 to 0.0102 min−1 with increase in current density from 0.01 to 0.03 A cm−2. This study showed that the COD reduction is more influenced by the current density. The linear and the nonlinear regression
models reveal that the COD reduction is influenced by the applied current density. 相似文献
47.
Bastihalli Tukaram Diwakar Pinto Kumar Dutta Belur Ramaswamy Lokesh Kamatham Akhilender Naidu 《Journal of the American Oil Chemists' Society》2010,87(5):539-548
Garden cress (Lepidium sativum L.) is an edible, underutilised herb, grown mainly for its seeds in India. Physicochemical properties, minor components (unsaponifiable
matter, tocopherols, carotenoids), fatty acid composition and storage stability of garden cress seed oil (GCO) were studied.
Cold press, solvent and supercritical CO2 extraction methods were employed to extract the oil. The total oil content of garden cress (GC) seeds was 21.54, 18.15 and
12.60% respectively by solvent, supercritical CO2 and cold press methods. The physical properties of GCO extracted by the above methods were similar in terms of refractive
index, specific gravity and viscosity. However, cold pressed oil showed low PV and FFA compared to the oil extracted by other
methods. α-Linolenic acid (34%) was the major fatty acid in GCO followed by oleic (22%), linoleic (11.8%), eicosanoic (12%),
palmitic (10.1%) erucic (4.4%), arachidic (3.4%) and stearic acids (2.9%). Oleic acid (39.9%) and α-linolenic acid (42.1%)
were the predominant fatty acids at the sn-2 position. The total tocopherol and carotenoid content of GCO was 327.42 and 1.0 μmol/100 g oil, respectively. The oil was
stable up to 4 months at 4 °C. Tocopherol and BHT offered the least protection, while ascorbyl palmitate (200 ppm) offered
the maximum protection to the oil, when subjected to the accelerated oxidative stability test. Thus GCO can be considered
as a fairly stable oil with a high content of α-linolenic acid. 相似文献
48.
49.
Santosh Kumar Gupta Brindaban Modak Mohit Tyagi Pampa Modak Kathi Sudarshan 《Journal of the American Ceramic Society》2023,106(2):1102-1112
Speciation of actinide (An) and lanthanide (Ln) in technologically important ceramics is very important from both fundamental as well as technological aspects. The intrinsic structural flexibility of perovskite containing AO6 and BO12 polyhedra makes them suitable and rich hosts for An and Ln. In this work, emphasis was given to deciphering information such as oxidation state, local dopant site, charge compensating defects, excited state kinetics, and so forth in BaHfO3 (BHO) related to dopant uranium (BHO-U) and cerium (BHO-Ce). Several spectroscopic techniques namely, time-resolved photoluminescence (TRPL), positron annihilation lifetime spectra (PALS), and thermoluminescence (TL) spectroscopy coupled with density functional theory (DFT) were employed to probe the same. Ce and U though are distributed at both Ba and Hf sites, Ce prefers the former, while U prefers the latter site. Uranium on the other hand stabilizes as U6+ in the form of octahedral uranate ion giving green emission. PALS suggested the formation of defects in BHO-Ce and BHO-U with oxygen vacancies predominating in the former whereas BHO-U perovskites are loaded with cation vacancies and vacancy clusters. These cation vacancies are responsible for lower TL output in BHO-U. TL measurements also suggested cerium doping leads to a higher density of deeper traps in BHO-Ce compared to uranium doping in BHO-U which is in concurrence with DFT results and may have implications in designing afterglow phosphors based on perovskite. We believe this work would have a long-term impact on exploring the potential of perovskite for nuclear waste host and afterglow phosphors applications. 相似文献
50.
G. V. Kunte Ujwala Ail P. K. Ajikumar A. K. Tyagi S. A. Shivashankar A. M. Umarji 《Bulletin of Materials Science》2011,34(7):1633-1637
A method for the estimation of vapour pressure and partial pressure of subliming compounds under reduced pressure, using rising temperature thermogravimetry, is described in this paper. The method is based on our recently developed procedure to estimate the vapour pressure from ambient pressure thermogravimetric data using Langmuir equation. Using benzoic acid as the calibration standard, vapour pressure-temperature curves are calculated at 80, 160 and 1000 mbar for salicylic acid and vanadyl bis-2,4-pentanedionate, a precursor used for chemical vapour deposition of vanadium oxides. Using a modification of the Langmuir equation, the partial pressure of these materials at different total pressures is also determined as a function of temperature. Such data can be useful for the deposition of multi-metal oxide thin films or doped thin films by chemical vapour deposition (CVD). 相似文献