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Complex scattering matrix parameters of a slot-coupled, waveguide tee junction are determined using a moment method of analysis with entire orthogonal basis functions and a rigorous analysis of the effect of wall thickness. The variations of the equivalent network parameter, coupling, and return loss with frequency are evaluated, and the results are compared with experimental data. The unitary property of the S matrix is verified. The dependence of coupling on slot length, slot width, and thickness is presented 相似文献
64.
Sankara Sarma V. Tatiparti Fereshteh Ebrahimi 《Journal of Applied Electrochemistry》2010,40(12):2091-2098
Al–Mg alloys were deposited using a base-electrolyte with the composition Na[AlEt4] + 2Na[Et3Al–H–AlEt3] + 2.5AlEt3 + 6toluene (where Et = −C2H5). Mg was introduced into this electrolyte by employing a pure Mg anode. It was found that initially the amount of Mg in the
electrolyte increased with the deposition time but eventually a steady state was reached such that the amount of Mg dissolved
at the anode became equal to that deposited at the cathode. Compositional and phase analyses indicated that this state is
achieved at a critical Mg/Al ratio that resulted in the formation of the hcp Mg-rich phase. By devising various component
electrolytes we have attempted to understand the roles of different compounds in the base-electrolyte and have proposed a
scheme for the Al–Mg alloy deposition. 相似文献
65.
Monima Sarma Tanmay Chatterjee Samar K. Das 《Inorganic chemistry communications》2010,13(10):1114-1117
The reaction between Cu(NO3)2·3H2O and a tetra-aza macrocycle, more specifically, cyclen in 1:1 MeCN–MeOH solvent mixture forms a Cu2+–cyclen coordination complex in situ, that has been reacted with an isopolyanion [W6O19]2? in a slow diffusion technique, resulting in the isolation of an ion-pair solid [Cu(cyclen)(MeCN)][W6O19] (1). Single crystal structural investigation on 1 shows a square pyramidal geometry around the metal centre (copper ion) with an axially bound MeCN solvent molecule. The title compound 1 is the first crystallographically characterized ion-pair compound, in which a transition metal coordination complex of a tetra-aza-crown ether (cyclen) has been associated with a polyoxometalate cluster anion. This communication deals with synthesis, spectroscopic, structural and electrochemical analyses of compound 1. 相似文献
66.
Kankana Baruah Riku Dutta Simanta Doley Bipul Sarma Swapan Kumar Dolui 《应用聚合物科学杂志》2024,141(2):e54767
Excess metal pollutant has affected and caused serious havoc in the lives of terrestrial as well as aquatic beings. The core of this work revolves around eradicating highly toxic heavy metal ions from underground water systems using a cost-effective, high removal efficiency polymeric adsorbent capable of adsorbing and removing ionic metals whose backbone is composed of a bio-degradable polymer, polyvinyl alcohol. The obtained adsorbent was characterized using FT-IR, HNMR, and P-XRD. Morphological studies were carried out using SEM. Detection and adsorption of metal ions were performed using SEM–EDX and AAS; wherein the adsorbent was found to remove nearly 80% of arsenic ions, 70.5% and 70.7% for lead and chromium ions while 60.7% for cadmium ions, respectively. Further, the kinetics of adsorption along with intraparticle diffusion studies were also performed to determine the mechanism alongside observing the isothermal influence of the sorbent. The adsorption capacity was seen to be highest in arsenic at around 570.42 mg g−1 thus acting as a potential and effective adsorbent for the removal of heavy metal ions from groundwater. 相似文献
67.
Sumantra Mandal A. K. Bhaduri V. Subramanya Sarma 《Metallurgical and Materials Transactions A》2011,42(4):1062-1072
Dynamic recrystallization (DRX) behavior in hot deformed (by uniaxial compression in a thermomechanical simulator in the temperatures
range 1173 K to 1373 K [900 °C to 1100 °C]) Ti-modified austenitic stainless steel was studied using electron back scatter
diffraction. Grain orientation spread with a “cut off” of 1 deg was a suitable criterion to partition dynamically recrystallized
grains from the deformed matrix. The extent of DRX increased with strain and temperature, and a completely DRX microstructure
with a fine grain size ~4 μm (considering twins as grain boundaries) was obtained in the sample deformed to a strain of 0.8 at 1373 K (1100 °C). The
nucleation of new DRX grains occurred by the bulging of the parent grain boundary. The DRX grains were twinned, and a linear
relationship was observed between the area fraction of DRX grains and the number fraction of Σ3 boundaries. The deviation
from the ideal misorientation of Σ3 boundaries decreased with an increase in the fraction of Σ3 boundaries (as well as the
area fraction of DRX) signifying that most Σ3 boundaries are newly nucleated during DRX. The generation of these Σ3 boundaries
could account for the formation of annealing twins during DRX. The role of Σ3 twin boundaries on DRX is discussed. 相似文献
68.
Mahadevan Balasubramaniam Yogesh Joshi Daniel Engels Sanjay Sarma Zafar Shaikh 《国际生产研究杂志》2013,51(18):4215-4238
An approach to tool selection and sequencing is presented for three-axis rough machining. The trade-off in the selection of tools is as follows: larger tools have reduced access while smaller tools are capable of reduced cutting speed. Furthermore, every tool change incurs a time penalty. The objective of this paper is to select a tool sequence that minimizes the total rough-machining time. In our approach, the removal volume is stratified into 2.5D machining slabs and, for each tool, the area accessible in each slab is computed incrementally, keeping in mind the cutting portion of the tool and the shape of the tool holder and spindle assembly. This reduces the three-axis problem to a series of two-axis problems with complex precedence constraints. Two models are presented to understand this new form of the problem. First, an integer linear programming formulation is discussed to show the complexity of the task. Second, a network flow formulation is presented, by which we show that it is possible to obtain efficiently an approximate solution of the problem. Examples are discussed to illustrate the algorithms discussed. 相似文献
69.
The amelioration effect of dietary high protein and vitamin C against stress was evaluated in spotted murrel, Channa punctatus, exposed to endosulfan. Two hundred and forty fish (average weight: 27.01 g/fish), distributed equally into 4 different groups (control, T1, T2, and T3), each with 6 replicates were fed with control (40% crude protein, CP and 0.1% vitamin C), T1 (40% CP and 0.1% vitamin C), T2 (50% CP and 0.1% vitamin C), and T3 (50% CP and 0.2% vitamin C) diets for 90 days. Groups fed T1, T2, and T3 diets were exposed to sublethal endosulfan concentration, whereas the control was maintained without endosulfan exposure. Results indicated significant reduction in the growth performance, survival, and activities of lactate dehydrogenase (liver and muscle), malate dehydrogenase (liver and muscle), enzymes of protein metabolism (aspartate amino transferase in liver and alanine amino transferase in liver and muscle), acetyl choline esterase (brain), alkaline phosphatase activity (liver), and ATPase (gill) enzymes of group fed control diet and exposed to endosulfan. However, endosulfan exposed fish fed high CP and vitamin C diet exhibited significant (P < 0.05) improvement in their growth performance and metabolic enzyme activities. Further, high CP and vitamin C diet reduced endosulfan accumulation in the muscle. Overall results indicate that vitamin C (0.2%) supplementation in high CP (50%) diet improves growth, metabolism, and reduce endosulfan bioaccumulation in C. punctatus. 相似文献
70.